Symptom-Based DDx & Plans — Cardiopulmonary

101. Shortness of Breath (Dyspnea)

/Dyspnea · differentiate first (cardiac vs pulmonary vs vascular), then treat the cause · CHF · pneumonia · COPD · asthma · PE · pleural effusion · ACS · Super Compact

Approach — sort dyspnea by the system, then treat that cause. The fastest split is cardiac (CHF, ACS) vs pulmonary (pneumonia, COPD, asthma, effusion) vs vascular (PE), driven by a focused history (orthopnea/PND, fever/sputum, wheeze, pleuritic pain, risk factors) plus the four bedside tests that triage almost everything: CXR, ECG, troponin, BNP — and a CTA/D-dimer if PE is in play. Stabilize oxygenation first (this is the symptom where airway/breathing comes before the workup), then let the discriminators point to the plan.

Key discriminators: orthopnea/PND/edema/S3 → CHF · fever/productive cough/focal crackles/consolidation → pneumonia · known COPD/smoking/prolonged expiration/wheeze → COPD · episodic wheeze/triggers/reversible → asthma · pleuritic pain/tachycardia/hypoxia out of proportion/leg swelling/VTE risk → PE · dullness/decreased breath sounds at a base → effusion · exertional pressure/diaphoresis/ECG-troponin changes → ACS

Initial Sx/Data (all comers): vitals + SpO2, focused cardiopulmonary exam (crackles, wheeze, breath-sound asymmetry, JVD, edema, calf); CXR, ECG, troponin, BNP, ABG/VBG if severe, CBC, BMP; D-dimer or CTA chest if PE considered; bedside ultrasound (B-lines, effusion, RV strain) where available · (don't anchor — CHF and pneumonia and PE coexist often, and the patient who is hypoxic out of proportion to the CXR is a PE until excluded)

Neg (don't-miss): denies missed ACS (get the ECG + troponin — MI can present as isolated dyspnea, esp diabetic/elderly/female) · denies missed PE (hypoxia out of proportion, clear CXR, tachycardia) · denies missed tension pneumothorax/impending respiratory failure (escalate airway first) · denies anchoring on one cause when several coexist

DDx: CHF exacerbation · pneumonia · COPD exacerbation · asthma exacerbation · pulmonary embolism · pleural effusion · acute coronary syndrome · (also: pneumothorax, anemia, metabolic acidosis, anxiety — exclude the dangerous first)

Plan — by Diagnosis

CONSULT (as relevant): Cardiology (ACS, decompensated CHF) · Pulmonology (COPD/asthma/effusion, respiratory failure) · ICU/Rapid Response (impending respiratory failure, hemodynamic instability)

CHF exacerbation

– Confirm: orthopnea/PND/edema/JVD/S3, BNP elevated, CXR congestion/effusions, B-lines on US; echo if needed
– Plan: IV loop diuretic — furosemide (e.g. 40 mg IV or ~2.5× the home daily PO dose IV), titrate to net diuresis; O2 to keep SpO2 ≥90%; NIPPV for respiratory distress/flash pulmonary edema; nitroglycerin (IV/SL) for hypertensive/symptom relief if not hypotensive; daily weights, strict I/O, Na/fluid restriction; identify trigger (ischemia, arrhythmia, dietary/med nonadherence); resume/optimize GDMT when stable
– Diuresis is the lever; NIPPV buys time in flash edema. Always ask what triggered it — ischemia and new AF are the common culprits.

Pneumonia

– Confirm: fever, productive cough, focal crackles, consolidation on CXR; cultures/sputum, consider procalcitonin
– Plan: empiric antibiotics per setting + severity (CAP: ceftriaxone + azithromycin, or respiratory fluoroquinolone; add MRSA/Pseudomonas coverage for HCAP/severe per risk); O2; assess severity (CURB-65/PSI) for floor vs ICU; fluids; cultures BEFORE antibiotics but don't delay; de-escalate by cultures
– Start antibiotics early; severity score decides disposition. Use institution-specific organisms (this institution uses cefepime in place of pip-tazo, plus metronidazole 500 mg IV q8h where anaerobic coverage is needed).

COPD exacerbation

– Confirm: known COPD/smoking, increased dyspnea/sputum volume or purulence, wheeze/prolonged expiration; CXR (exclude pneumonia/pneumothorax), ABG/VBG (CO2)
– Plan: inhaled bronchodilators (albuterol + ipratropium nebs), systemic glucocorticoids (e.g. prednisone 40 mg PO daily ~5 days), antibiotics if increased sputum purulence/volume or mechanical ventilation (e.g. azithromycin or doxycycline per setting); controlled O2 (target SpO2 88–92% — avoid over-oxygenation), NIPPV for hypercapnic respiratory failure/acidosis
– NIPPV is the intervention that prevents intubation in hypercapnic COPD. Don't over-oxygenate; the target is 88–92%.

Asthma exacerbation

– Confirm: episodic wheeze/triggers, prior asthma, reversible airflow obstruction; peak flow; CXR if atypical
– Plan: inhaled SABA (albuterol, continuous or frequent neb) + ipratropium, early systemic glucocorticoids (prednisone 40–60 mg PO or IV methylprednisolone), O2; magnesium sulfate IV for severe; reassess peak flow/work of breathing; watch for fatigue/silent chest/rising CO2 → ICU + possible intubation
– A normalizing or rising CO2 in a tiring asthmatic is an ominous sign — escalate, don't reassure.

Pulmonary embolism

– Confirm: pleuritic pain, hypoxia out of proportion, tachycardia, VTE risk/leg swelling; D-dimer (low pretest), CTA chest (or V/Q); RV strain on echo/ECG/troponin/BNP risk-stratifies
– Plan: anticoagulation (e.g. LMWH or DOAC; UFH if unstable/procedure likely) unless contraindicated; massive/hemodynamically unstable PE → thrombolysis + ICU; submassive (RV strain) → monitored setting, consider escalation; O2; assess bleeding risk
– Stability + RV strain drive disposition: hypotension means thrombolysis, RV strain means a monitored bed.

Pleural effusion

– Confirm: dullness + decreased breath sounds at the base, effusion on CXR/US; diagnostic thoracentesis (Light's criteria — exudate vs transudate)
– Plan: thoracentesis for diagnosis + symptom relief if significant/symptomatic; treat the cause (diurese transudate from CHF; treat parapneumonic/empyema with antibiotics ± chest tube/drainage; malignant → oncology/drainage); send fluid studies (cell count, protein, LDH, pH, cytology, cultures)
– A complicated parapneumonic effusion or empyema (low pH, loculations) needs drainage, not just antibiotics.

Acute coronary syndrome

– Confirm: exertional pressure/diaphoresis (or anginal-equivalent dyspnea), ECG changes, troponin rise
– Plan: aspirin, ECG + serial troponin; STEMI → emergent reperfusion (PCI); NSTEMI/UA → antithrombotic therapy + cardiology + risk-stratified angiography; treat dyspnea/heart failure if present; see the chest pain card's ACS approach for full detail
– Dyspnea can be the only ACS symptom in diabetics, the elderly, and women — always get the ECG and troponin.

Cross-cutting

– Trend: SpO2/work of breathing, response to the targeted therapy, the discriminating test results, trigger identification
– Escalation triggers: impending respiratory failure (fatigue, rising CO2, falling SpO2 on max support) → ICU + airway/NIPPV/intubation; hemodynamic instability → ICU; massive PE → thrombolysis; STEMI → emergent PCI; tension pneumothorax → immediate decompression
– Discharge checklist: cause identified + treated + oxygenation stable on room air (or baseline); trigger addressed; cause-specific follow-up (cardiology/pulmonology); inhaler/diuretic/anticoagulation teaching as relevant; return precautions (worsening dyspnea, chest pain, fever, leg swelling)

101. Shortness of Breath (Dyspnea)

/Dyspnea · complete reference · differentiate cardiac vs pulmonary vs vascular, stabilize oxygenation, then a focused plan per cause · Full Card

Approach — Differentiate, Then Treat the Cause

• The fastest split is cardiac (CHF, ACS) versus pulmonary (pneumonia, COPD, asthma, effusion) versus vascular (PE), driven by a focused history (orthopnea or PND, fever or sputum, wheeze, pleuritic pain, risk factors) plus the four bedside tests that triage almost everything: CXR, ECG, troponin, and BNP — and a CTA or D-dimer if PE is in play.

• Stabilize oxygenation first — this is the symptom where airway and breathing come before the workup — then let the discriminators point to the plan.

• Key discriminators: orthopnea, PND, edema, and an S3 → CHF; fever, productive cough, focal crackles, and consolidation → pneumonia; known COPD, smoking, prolonged expiration, and wheeze → COPD; episodic wheeze, triggers, and reversibility → asthma; pleuritic pain, tachycardia, hypoxia out of proportion, leg swelling, and VTE risk → PE; dullness and decreased breath sounds at a base → effusion; exertional pressure, diaphoresis, and ECG or troponin changes → ACS.

• Don't anchor — CHF, pneumonia, and PE often coexist, and the patient who is hypoxic out of proportion to the CXR is a PE until excluded.

Initial Symptoms / Data (all comers)

• Vitals including SpO2, and a focused cardiopulmonary exam (crackles, wheeze, breath-sound asymmetry, JVD, edema, calf exam).

• CXR, ECG, troponin, BNP, an ABG or VBG if severe, CBC, and BMP; a D-dimer or CTA chest if PE is considered; bedside ultrasound (B-lines, effusion, RV strain) where available.

Neg (don't-miss)

• Pt denies a missed ACS (get the ECG and troponin — MI can present as isolated dyspnea, especially in diabetic, elderly, or female patients) and a missed PE (hypoxia out of proportion, a clear CXR, tachycardia).

• Pt denies a missed tension pneumothorax or impending respiratory failure (escalate the airway first).

• Pt denies anchoring on one cause when several coexist.

DDx

CHF exacerbation · pneumonia · COPD exacerbation · asthma exacerbation · pulmonary embolism · pleural effusion · acute coronary syndrome · (also: pneumothorax, anemia, metabolic acidosis, anxiety — exclude the dangerous causes first)

Plan — by Diagnosis

CONSULT (as relevant): Cardiology (ACS, decompensated CHF) · Pulmonology (COPD, asthma, effusion, respiratory failure) · ICU or Rapid Response (impending respiratory failure, hemodynamic instability)

• CHF exacerbation — confirm: orthopnea, PND, edema, JVD, and an S3, with an elevated BNP, congestion and effusions on CXR, and B-lines on ultrasound; echo if needed. Plan: an IV loop diuretic — furosemide (e.g. 40 mg IV or about 2.5 times the home daily PO dose given IV), titrated to net diuresis; O2 to keep SpO2 at least 90%; NIPPV for respiratory distress or flash pulmonary edema; nitroglycerin (IV or SL) for hypertensive presentations or symptom relief if not hypotensive; daily weights, strict I/O, and sodium and fluid restriction; identify the trigger (ischemia, arrhythmia, dietary or medication nonadherence); resume and optimize guideline-directed medical therapy when stable.

• Pneumonia — confirm: fever, productive cough, focal crackles, and consolidation on CXR; cultures and sputum, consider procalcitonin. Plan: empiric antibiotics per setting and severity (CAP: ceftriaxone plus azithromycin, or a respiratory fluoroquinolone; add MRSA or Pseudomonas coverage for healthcare-associated or severe disease per risk); O2; assess severity (CURB-65 or PSI) for floor versus ICU; fluids; cultures before antibiotics but don't delay; de-escalate by cultures.

• COPD exacerbation — confirm: known COPD or smoking, increased dyspnea and sputum volume or purulence, and wheeze or prolonged expiration; CXR (exclude pneumonia or pneumothorax), ABG or VBG (CO2). Plan: inhaled bronchodilators (albuterol plus ipratropium nebulizers), systemic glucocorticoids (e.g. prednisone 40 mg PO daily for about 5 days), and antibiotics if there is increased sputum purulence or volume or mechanical ventilation (e.g. azithromycin or doxycycline per setting); controlled O2 (target SpO2 88–92% — avoid over-oxygenation), and NIPPV for hypercapnic respiratory failure or acidosis.

• Asthma exacerbation — confirm: episodic wheeze and triggers, prior asthma, and reversible airflow obstruction; peak flow; CXR if atypical. Plan: inhaled SABA (albuterol, continuous or frequent nebulizer) plus ipratropium, early systemic glucocorticoids (prednisone 40–60 mg PO or IV methylprednisolone), and O2; IV magnesium sulfate for severe disease; reassess peak flow and work of breathing; watch for fatigue, a silent chest, or a rising CO2 → ICU and possible intubation.

• Pulmonary embolism — confirm: pleuritic pain, hypoxia out of proportion, tachycardia, and VTE risk or leg swelling; a D-dimer (low pretest probability), a CTA chest (or V/Q scan); RV strain on echo, ECG, troponin, and BNP risk-stratifies. Plan: anticoagulation (e.g. LMWH or a DOAC; UFH if unstable or a procedure is likely) unless contraindicated; a massive or hemodynamically unstable PE → thrombolysis and ICU; submassive (RV strain) → a monitored setting, consider escalation; O2; assess bleeding risk.

• Pleural effusion — confirm: dullness and decreased breath sounds at the base, with an effusion on CXR or ultrasound; a diagnostic thoracentesis (Light's criteria — exudate versus transudate). Plan: thoracentesis for diagnosis and symptom relief if significant or symptomatic; treat the cause (diurese a transudate from CHF; treat a parapneumonic effusion or empyema with antibiotics and possible chest tube or drainage; malignant → oncology and drainage); send fluid studies (cell count, protein, LDH, pH, cytology, cultures).

• Acute coronary syndrome — confirm: exertional pressure and diaphoresis (or an anginal-equivalent dyspnea), with ECG changes and a troponin rise. Plan: aspirin, ECG, and serial troponin; STEMI → emergent reperfusion (PCI); NSTEMI or unstable angina → antithrombotic therapy, cardiology, and risk-stratified angiography; treat dyspnea or heart failure if present (see the chest pain card's ACS approach for full detail).

• Cross-cutting — trend: SpO2 and work of breathing, the response to the targeted therapy, the discriminating test results, and trigger identification.

• Escalation triggers: impending respiratory failure (fatigue, a rising CO2, a falling SpO2 on maximal support) → ICU and airway management, NIPPV, or intubation; hemodynamic instability → ICU; massive PE → thrombolysis; STEMI → emergent PCI; tension pneumothorax → immediate decompression.

• Discharge checklist: the cause identified and treated with stable oxygenation on room air (or baseline); the trigger addressed; cause-specific follow-up (cardiology or pulmonology); inhaler, diuretic, or anticoagulation teaching as relevant; return precautions for worsening dyspnea, chest pain, fever, or leg swelling.

Red Flags

• Hypoxia out of proportion to a clear CXR with tachycardia → pulmonary embolism until excluded.

• Isolated dyspnea in a diabetic, elderly, or female patient → could be an ACS anginal equivalent; get the ECG and troponin.

• A rising or normalizing CO2 in a tiring asthmatic or hypercapnic COPD patient → impending respiratory failure; escalate.

• Hypotension with PE → massive PE; thrombolysis and ICU.

• Sudden severe dyspnea with tracheal deviation and absent breath sounds → tension pneumothorax; immediate decompression.

Senior IM Resident Pearls

• Stabilize before you diagnose. Oxygenation and work of breathing come first; the CXR, ECG, troponin, and BNP sort the cause right behind it.

• The four tests triage almost everything. CXR, ECG, troponin, and BNP — add a CTA or D-dimer when PE is plausible.

• Hypoxia out of proportion to the film is a PE. A clear CXR with profound hypoxia and tachycardia should not reassure you.

• NIPPV prevents intubation. In flash pulmonary edema and hypercapnic COPD, it's the intervention that turns the corner.

• Don't over-oxygenate the COPD patient. Target 88–92%; a rising CO2 on high-flow O2 is a real hazard.

• Causes coexist. The CHF patient can also have a PE or pneumonia — treat what you find and keep looking if they don't improve.

• Common mistake: anchoring on CHF and diuresing a hypoxic patient whose real problem is a PE or pneumonia — let the discriminators, not the first impression, choose the plan.

Symptom-Based DDx & Plans — Cardiopulmonary

102. Chest Pain

/ChestPain · differentiate first (exclude the lethal: ACS, PE, dissection), then treat the cause · ACS · stable/unstable angina · GERD · PE · pericarditis · musculoskeletal · Super Compact

Approach — chest pain is a rule-out-the-killers problem first. Before comfort with a benign cause, exclude the immediately life-threatening: ACS, pulmonary embolism, aortic dissection (and tension pneumothorax, esophageal rupture). The triaging tests are ECG + serial troponin for every concerning chest pain, plus CXR, and CTA (PE or dissection) when the story or exam points there. Only once the dangerous are addressed do you settle on GERD, musculoskeletal, or pericarditis.

Key discriminators: exertional pressure/radiation/diaphoresis + ECG-troponin change → ACS · predictable exertional, relieved by rest → stable angina; rest/crescendo → unstable · burning, postprandial, positional/acid, relieved by antacids → GERD · pleuritic + dyspnea + hypoxia + VTE risk → PE · sharp, pleuritic, positional (worse supine, better leaning forward), friction rub, diffuse ST elevation/PR depression → pericarditis · reproducible with palpation/movement, localized → musculoskeletal · tearing pain to the back + pulse/BP differential → dissection (don't miss)

Initial Sx/Data (all comers): vitals (both arms if dissection considered), focused cardiopulmonary exam; ECG immediately (repeat if ongoing/evolving), serial troponin, CXR; D-dimer/CTA for PE, CTA aorta for dissection per suspicion; risk score (HEART) to support disposition · (get the ECG within minutes — STEMI is time-critical; and a single normal troponin doesn't exclude evolving ACS — trend it)

Neg (don't-miss): denies missed ACS/STEMI (immediate ECG + serial troponin) · denies missed aortic dissection (tearing pain to back, pulse/BP differential, widened mediastinum) · denies missed PE (pleuritic, hypoxia, VTE risk) · denies missed tension pneumothorax/esophageal rupture · denies discharging undifferentiated high-risk pain

DDx: acute coronary syndrome · stable/unstable angina · GERD · pulmonary embolism · pericarditis · musculoskeletal pain · (also: aortic dissection, pneumothorax, esophageal rupture, anxiety — exclude the lethal first)

Plan — by Diagnosis

CONSULT (as relevant): Cardiology (ACS, unstable angina) · Cardiothoracic/Vascular surgery (dissection) · GI (refractory GERD/esophageal) · ICU (STEMI, dissection, massive PE, instability)

Acute coronary syndrome

– Confirm: exertional/pressure pain ± radiation/diaphoresis, ECG changes, troponin rise
– Plan: aspirin (chewed) + ECG + serial troponin; STEMI → emergent reperfusion (PCI, door-to-balloon); NSTEMI/UA → dual antiplatelet + anticoagulation (e.g. heparin) + cardiology + risk-stratified angiography; nitrates (if not hypotensive/RV infarct/PDE5 use), beta-blocker (if no contraindication), high-intensity statin; treat complications
– Aspirin + ECG now; STEMI is a clock. Avoid nitrates in inferior/RV infarct and recent PDE5 inhibitors.

Stable / unstable angina

– Confirm: stable = predictable exertional, relieved by rest/nitro; unstable = rest/new/crescendo (an ACS — treat as above)
– Plan: unstable angina → treat as ACS (antithrombotics + cardiology); stable → anti-anginal therapy (beta-blocker, nitrates), aspirin + statin, risk-factor modification, outpatient ischemia evaluation/stress testing
– "Unstable" is in the ACS bucket; rest or crescendo pain is not an outpatient problem.

GERD

– Confirm: burning/postprandial, acid taste, positional, relieved by antacids — a diagnosis of exclusion after cardiac causes addressed
– Plan: PPI (e.g. omeprazole) trial, antacids; lifestyle (avoid triggers, head-of-bed elevation); GI referral/endoscopy if alarm features (dysphagia, weight loss, bleeding, refractory)
– Don't anchor on GERD in someone with cardiac risk until the ECG and troponin are clean — the "GI cocktail" response doesn't rule out ACS.

Pulmonary embolism

– Confirm: pleuritic pain, dyspnea, hypoxia, tachycardia, VTE risk; D-dimer (low pretest) / CTA chest; RV strain risk-stratifies
– Plan: anticoagulation (LMWH/DOAC; UFH if unstable) unless contraindicated; massive/unstable → thrombolysis + ICU; O2; see the dyspnea card's PE approach
– Pleuritic chest pain with hypoxia and tachycardia earns a PE workup, not reassurance.

Pericarditis

– Confirm: sharp pleuritic pain, worse supine/better leaning forward, friction rub, diffuse ST elevation + PR depression on ECG; echo (effusion/tamponade)
– Plan: NSAIDs (e.g. ibuprofen) + colchicine (reduces recurrence); treat the cause; watch for effusion/tamponade (hypotension, JVD, muffled heart sounds, pulsus paradoxus) → urgent echo ± pericardiocentesis; restrict exertion
– Colchicine added to NSAIDs cuts recurrence. The feared complication is tamponade — look for it.

Musculoskeletal pain

– Confirm: reproducible with palpation/movement, localized, positional; normal ECG/troponin — a diagnosis of exclusion in low-risk patients
– Plan: NSAIDs/acetaminophen, activity modification, reassurance after the dangerous causes are excluded; address costochondritis/strain
– Reproducible pain lowers but doesn't zero the probability of ACS; clear the killers in higher-risk patients first.

Cross-cutting

– Trend: ECG evolution, serial troponin, response to targeted therapy, hemodynamics
– Escalation triggers: STEMI → emergent PCI; aortic dissection → emergent surgery/BP control + ICU; massive PE → thrombolysis; tamponade → pericardiocentesis; hemodynamic instability → ICU
– Discharge checklist: lethal causes excluded + cause treated; HEART/risk-appropriate disposition; cardiology/GI follow-up as relevant; antiplatelet/statin/PPI teaching as relevant; return precautions (recurrent/worsening pain, dyspnea, syncope, diaphoresis)

102. Chest Pain

/ChestPain · complete reference · exclude the killers (ACS, PE, dissection) with ECG + troponin first, then a focused plan per cause · Full Card

Approach — Rule Out the Killers First

• Before settling on a benign cause, exclude the immediately life-threatening: ACS, pulmonary embolism, and aortic dissection (and tension pneumothorax, esophageal rupture).

• The triaging tests are an ECG and serial troponin for every concerning chest pain, plus a CXR, and a CTA (for PE or dissection) when the story or exam points there.

• Key discriminators: exertional pressure, radiation, and diaphoresis with an ECG or troponin change → ACS; predictable exertional pain relieved by rest → stable angina, rest or crescendo pain → unstable; burning, postprandial, positional or acid pain relieved by antacids → GERD; pleuritic pain with dyspnea, hypoxia, and VTE risk → PE; sharp, pleuritic, positional pain (worse supine, better leaning forward) with a friction rub and diffuse ST elevation and PR depression → pericarditis; pain reproducible with palpation or movement and localized → musculoskeletal; tearing pain radiating to the back with a pulse or BP differential → dissection (don't miss).

• Get the ECG within minutes — STEMI is time-critical; and a single normal troponin doesn't exclude evolving ACS — trend it.

Initial Symptoms / Data (all comers)

• Vitals (both arms if dissection is considered) and a focused cardiopulmonary exam.

• An ECG immediately (repeat if ongoing or evolving), serial troponin, and CXR; a D-dimer or CTA for PE, and a CTA aorta for dissection per suspicion; a risk score (HEART) to support disposition.

Neg (don't-miss)

• Pt denies a missed ACS or STEMI (immediate ECG and serial troponin) and a missed aortic dissection (tearing pain to the back, a pulse or BP differential, a widened mediastinum).

• Pt denies a missed PE (pleuritic pain, hypoxia, VTE risk) and a missed tension pneumothorax or esophageal rupture.

• Pt denies discharging undifferentiated high-risk pain.

DDx

Acute coronary syndrome · stable or unstable angina · GERD · pulmonary embolism · pericarditis · musculoskeletal pain · (also: aortic dissection, pneumothorax, esophageal rupture, anxiety — exclude the lethal causes first)

Plan — by Diagnosis

CONSULT (as relevant): Cardiology (ACS, unstable angina) · Cardiothoracic or Vascular surgery (dissection) · GI (refractory GERD or esophageal disease) · ICU (STEMI, dissection, massive PE, instability)

• Acute coronary syndrome — confirm: exertional or pressure pain with possible radiation and diaphoresis, ECG changes, and a troponin rise. Plan: aspirin (chewed), ECG, and serial troponin; STEMI → emergent reperfusion (PCI, door-to-balloon time); NSTEMI or unstable angina → dual antiplatelet therapy and anticoagulation (e.g. heparin), cardiology, and risk-stratified angiography; nitrates (if not hypotensive, RV infarct, or recent PDE5 use), a beta-blocker (if no contraindication), and a high-intensity statin; treat complications.

• Stable / unstable angina — confirm: stable is predictable exertional pain relieved by rest or nitroglycerin; unstable is rest, new, or crescendo pain (an ACS — treat as above). Plan: unstable angina → treat as ACS (antithrombotics and cardiology); stable → anti-anginal therapy (a beta-blocker, nitrates), aspirin and a statin, risk-factor modification, and outpatient ischemia evaluation or stress testing.

• GERD — confirm: burning or postprandial pain, an acid taste, a positional component, and relief with antacids — a diagnosis of exclusion after cardiac causes are addressed. Plan: a PPI (e.g. omeprazole) trial and antacids; lifestyle measures (avoid triggers, head-of-bed elevation); GI referral or endoscopy if there are alarm features (dysphagia, weight loss, bleeding, refractory symptoms).

• Pulmonary embolism — confirm: pleuritic pain, dyspnea, hypoxia, tachycardia, and VTE risk; a D-dimer (low pretest probability) or CTA chest; RV strain risk-stratifies. Plan: anticoagulation (LMWH or a DOAC; UFH if unstable) unless contraindicated; a massive or unstable PE → thrombolysis and ICU; O2 (see the dyspnea card's PE approach).

• Pericarditis — confirm: sharp pleuritic pain, worse supine and better leaning forward, a friction rub, and diffuse ST elevation with PR depression on ECG; echo (effusion or tamponade). Plan: NSAIDs (e.g. ibuprofen) plus colchicine (reduces recurrence); treat the cause; watch for effusion or tamponade (hypotension, JVD, muffled heart sounds, pulsus paradoxus) → urgent echo and possible pericardiocentesis; restrict exertion.

• Musculoskeletal pain — confirm: pain reproducible with palpation or movement, localized and positional, with a normal ECG and troponin — a diagnosis of exclusion in low-risk patients. Plan: NSAIDs or acetaminophen, activity modification, and reassurance after the dangerous causes are excluded; address costochondritis or strain.

• Cross-cutting — trend: ECG evolution, serial troponin, the response to targeted therapy, and hemodynamics.

• Escalation triggers: STEMI → emergent PCI; aortic dissection → emergent surgery, BP control, and ICU; massive PE → thrombolysis; tamponade → pericardiocentesis; hemodynamic instability → ICU.

• Discharge checklist: the lethal causes excluded and the cause treated; a HEART- or risk-appropriate disposition; cardiology or GI follow-up as relevant; antiplatelet, statin, or PPI teaching as relevant; return precautions for recurrent or worsening pain, dyspnea, syncope, or diaphoresis.

Red Flags

• ECG changes or a troponin rise → ACS; aspirin and a time-critical reperfusion pathway for STEMI.

• Tearing pain to the back with a pulse or BP differential or a widened mediastinum → aortic dissection; emergent imaging and surgery.

• Pleuritic pain with hypoxia and tachycardia → pulmonary embolism; CTA and anticoagulation.

• Hypotension, JVD, and muffled heart sounds in pericarditis → tamponade; urgent echo and pericardiocentesis.

• A normal first troponin → doesn't exclude evolving ACS; trend it before reassuring.

Senior IM Resident Pearls

• ECG in minutes. Every concerning chest pain gets an immediate ECG — STEMI is a clock, not a workup.

• One troponin isn't enough. Evolving ACS declares itself on the trend; a single normal value doesn't clear it.

• Don't let a GI cocktail fool you. Relief with antacids doesn't exclude ACS — clear the cardiac workup first.

• Reproducible pain isn't zero risk. Palpable chest pain lowers the odds of ACS but doesn't eliminate it in higher-risk patients.

• Add colchicine in pericarditis. It reduces recurrence on top of NSAIDs — and always look for tamponade.

• Avoid nitrates in inferior or RV infarct. And in recent PDE5 inhibitor use — the hypotension can be dangerous.

• Common mistake: labeling chest pain "musculoskeletal" or "GERD" in a higher-risk patient before the ECG, troponin trend, and dissection or PE consideration are complete.

Symptom-Based DDx & Plans — Neurologic

103. Altered Mental Status (AMS)

/AlteredMentalStatus · differentiate first (check the reversible quickly), then treat the cause · delirium · infection · stroke · medication toxicity · electrolytes · dementia progression · Super Compact

Approach — check the immediately reversible, then differentiate. AMS is a final common pathway: first check the things that kill or reverse in minutes — glucose, oxygenation, and obvious opioid/benzo toxicity (give dextrose / naloxone if indicated), screen for trauma. Then differentiate the cause with a structured sweep — infection, metabolic/electrolyte, drugs/toxins, structural (stroke), and the acute-on-chronic picture of delirium superimposed on dementia. Most inpatient AMS is delirium with a findable trigger.

Key discriminators: acute, fluctuating, inattentive + a trigger (infection, drugs, metabolic) → delirium · fever/leukocytosis/source → infection · FOCAL deficit / sudden onset → stroke (don't miss — time-critical) · new sedating/anticholinergic med or polypharmacy → medication toxicity · low Na/Ca, high Ca, uremia, hypoglycemia → electrolyte/metabolic · gradual, chronic, baseline-confirmed decline → dementia progression (a diagnosis of exclusion acutely)

Initial Sx/Data (all comers): fingerstick glucose immediately, vitals + SpO2, focused neuro exam (focality, pupils), medication review; CBC, BMP (Na/Ca/glucose/renal), LFTs/ammonia if indicated, UA/cultures, ABG/VBG, TSH; CT head for focal deficit/trauma/anticoagulation/no clear cause; consider LP (meningitis), EEG (nonconvulsive seizure); collateral history + baseline · (the single most time-critical miss is an acute stroke with focal signs — and don't forget nonconvulsive status and meningitis when nothing else fits)

Neg (don't-miss): denies missed hypoglycemia/hypoxia (checked first) · denies missed stroke (focal deficit, sudden — time-critical) · denies missed meningitis/encephalitis (fever + AMS + headache/neck stiffness → LP) · denies missed nonconvulsive status epilepticus (unexplained persistent AMS → EEG) · denies missed Wernicke/intoxication-withdrawal · denies anchoring on "dementia/sundowning" without a workup

DDx: delirium · infection · stroke · medication toxicity · electrolyte/metabolic abnormality · dementia progression · (also: nonconvulsive seizure, intoxication/withdrawal, Wernicke, hypoxia/hypercarbia, urinary retention/constipation in elderly)

Plan — by Diagnosis

CONSULT (as relevant): Neurology (stroke, seizure, unexplained) · Psychiatry/Geriatrics (delirium management) · ICU (airway compromise, status, instability)

Delirium

– Confirm: acute, fluctuating, inattention + an identifiable trigger; CAM-positive
– Plan: find and treat the trigger (infection, drugs, metabolic, pain, retention/constipation, hypoxia); non-pharmacologic first: reorientation, sleep-wake normalization, mobility, sensory aids (glasses/hearing), remove tethers/lines, avoid deliriogenic meds; low-dose antipsychotic ONLY for severe agitation endangering safety (not routine); avoid benzodiazepines except in withdrawal
– Delirium is a symptom — the work is finding the trigger. Benzos worsen it except in alcohol/benzo withdrawal.

Infection

– Confirm: fever/leukocytosis/localizing source (UTI, pneumonia, etc.); cultures, UA, CXR
– Plan: identify the source + empiric antibiotics per source/severity; sepsis pathway if criteria met (cultures, fluids, lactate, early antibiotics); treat — AMS often clears as infection is controlled
– In the elderly, infection (esp UTI/pneumonia) commonly presents as AMS without classic symptoms.

Stroke

– Confirm: focal deficit, sudden onset; urgent CT head (± CTA/perfusion), establish last-known-well
– Plan: activate stroke pathway/neurology emergently; ischemic within window → thrombolysis ± thrombectomy eligibility; hemorrhage → BP control + neurosurgery; NPO/aspiration precautions; see the relevant stroke workflow
– Time is brain — focal AMS gets an emergent CT and a stroke activation, not an observation period.

Medication toxicity

– Confirm: new/culprit drug (opioids, benzos, anticholinergics, sedatives), polypharmacy, renal/hepatic accumulation
– Plan: stop/reduce the offending agent; reversal where appropriate (naloxone for opioids; flumazenil rarely/cautiously); supportive care; renal/hepatic dose-adjust; review the full list for anticholinergic burden
– Deprescribing is the treatment. Anticholinergic burden is an underappreciated cause in older adults.

Electrolyte / metabolic

– Confirm: Na (hypo/hyper), Ca (hypo/hyper), glucose, uremia, hepatic (ammonia), thyroid on labs
– Plan: correct the specific abnormality at the appropriate rate (e.g. cautious sodium correction to avoid osmotic demyelination; treat hypercalcemia; lactulose for hepatic encephalopathy; glucose management); treat the underlying driver
– Correct sodium at a safe rate — overcorrection causes osmotic demyelination.

Dementia progression

– Confirm: gradual, chronic decline confirmed against baseline — a diagnosis of exclusion acutely (rule out superimposed delirium first)
– Plan: exclude acute reversible causes first; supportive care, environmental measures, caregiver support, goals-of-care discussion; address safety; avoid over-medication
– "Sundowning"/dementia is the label after you've excluded delirium, not a reason to skip the workup.

Cross-cutting

– Trend: mental status (CAM/exam), the corrected driver, vitals/glucose, response to treatment
– Escalation triggers: airway compromise/GCS drop → ICU + airway; stroke → emergent neuro/reperfusion; nonconvulsive status → EEG + treat; meningitis → urgent LP + antibiotics; severe metabolic derangement → correct urgently
– Discharge checklist: reversible causes excluded/treated + mental status improving toward baseline; deliriogenic meds addressed; cognitive/safety follow-up; collateral-informed baseline documented; return precautions (worsening confusion, focal deficit, fever, decreased responsiveness)

103. Altered Mental Status (AMS)

/AlteredMentalStatus · complete reference · check glucose/oxygen/toxidromes first, exclude stroke and meningitis, then treat the cause · Full Card

Approach — Reversible First, Then Differentiate

• AMS is a final common pathway: first check the things that kill or reverse in minutes — glucose, oxygenation, and obvious opioid or benzodiazepine toxicity (give dextrose or naloxone if indicated) — and screen for trauma.

• Then differentiate the cause with a structured sweep — infection, metabolic or electrolyte derangement, drugs or toxins, structural disease (stroke), and the acute-on-chronic picture of delirium superimposed on dementia.

• Key discriminators: acute, fluctuating inattention with a trigger (infection, drugs, metabolic) → delirium; fever, leukocytosis, or a source → infection; a focal deficit or sudden onset → stroke (don't miss — time-critical); a new sedating or anticholinergic medication or polypharmacy → medication toxicity; a low sodium or calcium, a high calcium, uremia, or hypoglycemia → electrolyte or metabolic cause; a gradual, chronic, baseline-confirmed decline → dementia progression (a diagnosis of exclusion acutely).

• Most inpatient AMS is delirium with a findable trigger.

Initial Symptoms / Data (all comers)

• A fingerstick glucose immediately, vitals with SpO2, a focused neuro exam (focality, pupils), and a medication review.

• CBC, BMP (sodium, calcium, glucose, renal function), LFTs and ammonia if indicated, UA and cultures, ABG or VBG, and TSH; a CT head for a focal deficit, trauma, anticoagulation, or no clear cause; consider an LP (meningitis) and EEG (nonconvulsive seizure); collateral history and baseline.

• The single most time-critical miss is an acute stroke with focal signs — and don't forget nonconvulsive status and meningitis when nothing else fits.

Neg (don't-miss)

• Pt denies a missed hypoglycemia or hypoxia (checked first) and a missed stroke (focal deficit, sudden onset — time-critical).

• Pt denies a missed meningitis or encephalitis (fever with AMS and headache or neck stiffness → LP) and a missed nonconvulsive status epilepticus (unexplained persistent AMS → EEG).

• Pt denies a missed Wernicke encephalopathy or intoxication-withdrawal and anchoring on "dementia" or "sundowning" without a workup.

DDx

Delirium · infection · stroke · medication toxicity · electrolyte or metabolic abnormality · dementia progression · (also: nonconvulsive seizure, intoxication or withdrawal, Wernicke encephalopathy, hypoxia or hypercarbia, urinary retention or constipation in the elderly)

Plan — by Diagnosis

CONSULT (as relevant): Neurology (stroke, seizure, unexplained AMS) · Psychiatry or Geriatrics (delirium management) · ICU (airway compromise, status epilepticus, instability)

• Delirium — confirm: acute, fluctuating inattention with an identifiable trigger; CAM-positive. Plan: find and treat the trigger (infection, drugs, metabolic derangement, pain, retention or constipation, hypoxia); non-pharmacologic measures first (reorientation, sleep-wake normalization, mobility, sensory aids like glasses and hearing aids, remove tethers and lines, avoid deliriogenic medications); a low-dose antipsychotic only for severe agitation endangering safety (not routine); avoid benzodiazepines except in withdrawal.

• Infection — confirm: fever, leukocytosis, or a localizing source (UTI, pneumonia); cultures, UA, CXR. Plan: identify the source and give empiric antibiotics per source and severity; the sepsis pathway if criteria are met (cultures, fluids, lactate, early antibiotics); treat — the AMS often clears as the infection is controlled.

• Stroke — confirm: a focal deficit and sudden onset; an urgent CT head (with possible CTA or perfusion), establish the last-known-well time. Plan: activate the stroke pathway and neurology emergently; ischemic stroke within the window → thrombolysis and thrombectomy eligibility; hemorrhage → BP control and neurosurgery; NPO and aspiration precautions (see the relevant stroke workflow).

• Medication toxicity — confirm: a new or culprit drug (opioids, benzodiazepines, anticholinergics, sedatives), polypharmacy, or renal or hepatic accumulation. Plan: stop or reduce the offending agent; reversal where appropriate (naloxone for opioids; flumazenil rarely and cautiously); supportive care; renal and hepatic dose adjustment; review the full list for anticholinergic burden.

• Electrolyte / metabolic — confirm: sodium (hypo or hyper), calcium (hypo or hyper), glucose, uremia, hepatic disease (ammonia), and thyroid on labs. Plan: correct the specific abnormality at the appropriate rate (e.g. cautious sodium correction to avoid osmotic demyelination; treat hypercalcemia; lactulose for hepatic encephalopathy; glucose management); treat the underlying driver.

• Dementia progression — confirm: a gradual, chronic decline confirmed against baseline — a diagnosis of exclusion acutely (rule out superimposed delirium first). Plan: exclude acute reversible causes first; supportive care, environmental measures, caregiver support, and a goals-of-care discussion; address safety; avoid over-medication.

• Cross-cutting — trend: mental status (CAM or exam), the corrected driver, vitals and glucose, and the response to treatment.

• Escalation triggers: airway compromise or a GCS drop → ICU and airway management; stroke → emergent neurology and reperfusion; nonconvulsive status → EEG and treat; meningitis → urgent LP and antibiotics; severe metabolic derangement → correct urgently.

• Discharge checklist: reversible causes excluded or treated and mental status improving toward baseline; deliriogenic medications addressed; cognitive and safety follow-up; a collateral-informed baseline documented; return precautions for worsening confusion, a focal deficit, fever, or decreased responsiveness.

Red Flags

• A focal neurologic deficit with sudden onset → stroke; emergent CT and stroke activation, not observation.

• Fever with AMS and headache or neck stiffness → meningitis or encephalitis; urgent LP and antibiotics.

• Persistent unexplained AMS → nonconvulsive status epilepticus; get an EEG.

• A low fingerstick glucose → hypoglycemia; treat before anything else.

• A declining GCS or airway compromise → ICU and airway protection.

Senior IM Resident Pearls

• Check the glucose first. It's the fastest reversible cause and is missed when the workup gets complicated.

• Delirium is a symptom, not a diagnosis. The work is hunting the trigger — infection, drugs, metabolic, pain, retention.

• Benzos worsen delirium. The exception is alcohol or benzodiazepine withdrawal; otherwise avoid them.

• Focal AMS is a stroke until proven otherwise. It earns an emergent CT and a stroke activation, not a period of watching.

• Elderly infection hides as AMS. A UTI or pneumonia can present with confusion and no classic symptoms.

• Correct sodium slowly. Overcorrection causes osmotic demyelination — pace it.

• Common mistake: calling new confusion "sundowning" or "dementia" and skipping the workup that would reveal a treatable delirium trigger.

Symptom-Based DDx & Plans — Infectious

104. Fever / Sepsis

/FeverSepsis · differentiate by SOURCE while resuscitating in parallel · pneumonia · UTI · cellulitis · bacteremia · intra-abdominal infection · Super Compact

Approach — resuscitate and find the source in parallel. Fever/sepsis is the symptom where the workup and treatment run together: assess for sepsis/septic shock (qSOFA/organ dysfunction, lactate) and start the sepsis bundle (cultures before antibiotics, broad empiric antibiotics within 1 hour, fluids for hypoperfusion) while you hunt the source. Then differentiate by the likely focus — lung, urine, skin, blood, abdomen — and tailor antibiotics + source control to it.

Key discriminators (find the source): cough/sputum/hypoxia/infiltrate → pneumonia · dysuria/frequency/flank pain/pyuria → UTI/pyelonephritis · erythema/warmth/swelling/skin breach → cellulitis · no localizing source + positive blood cultures / indwelling line/device → bacteremia · abdominal pain/tenderness/peritoneal signs → intra-abdominal infection (needs source control)

Initial Sx/Data (all comers): vitals (temp, BP, HR, RR, SpO2), perfusion/mentation; blood cultures ×2 BEFORE antibiotics, lactate, CBC, BMP, UA + urine culture, CXR; source-directed imaging (CT abdomen/pelvis for intra-abdominal, US for abscess); consider procalcitonin; full skin/line/device exam · (don't delay antibiotics to complete the workup in septic shock — and always look for a source needing drainage, because antibiotics alone won't cure an undrained abscess or obstructed system)

Neg (don't-miss): denies undrained source / missed source control (abscess, obstructed/infected urinary system, empyema, necrotizing infection — antibiotics alone fail) · denies missed necrotizing fasciitis (pain out of proportion, rapid progression, crepitus → surgical emergency) · denies missed neutropenic fever / meningitis / endocarditis · denies delaying antibiotics in septic shock · denies missed non-infectious fever (VTE, drug, etc.)

DDx: pneumonia · UTI/pyelonephritis · cellulitis · bacteremia · intra-abdominal infection · (also: meningitis, endocarditis, line infection, C. difficile, necrotizing soft-tissue infection, non-infectious fever)

Plan — by Source

CONSULT (as relevant): Infectious Disease (complex/resistant, bacteremia, endocarditis) · Surgery/IR (source control — drainage, debridement) · ICU (septic shock, organ dysfunction) · Urology (obstructed infected system)

Pneumonia

– Confirm: cough/sputum/hypoxia, focal exam, infiltrate on CXR; sputum/blood cultures
– Plan: empiric antibiotics per setting/severity (CAP: ceftriaxone + azithromycin or respiratory fluoroquinolone; add MRSA/Pseudomonas for HCAP/severe per risk); O2; severity score (CURB-65/PSI) for disposition; de-escalate by cultures
– Severity score decides floor vs ICU; this institution uses cefepime in place of pip-tazo (+ metronidazole 500 mg IV q8h for anaerobes).

UTI / Pyelonephritis

– Confirm: dysuria/frequency/flank pain, pyuria + positive urine culture; imaging if obstruction/abscess suspected
– Plan: empiric antibiotics per severity + local resistance (e.g. ceftriaxone for pyelonephritis; tailor by culture); obstructed infected system (stone/hydronephrosis) → urgent urology/IR decompression (source control); hydration
– An obstructed, infected kidney is a urologic emergency — antibiotics won't fix it without decompression.

Cellulitis

– Confirm: erythema/warmth/swelling/tenderness, skin breach/portal; mark the border
– Plan: antibiotics covering streptococci ± Staph (MRSA coverage per risk/purulence — e.g. cephalexin or vancomycin if MRSA/severe); elevate; treat the portal of entry; if pain out of proportion/rapid spread/crepitus/systemic toxicity → exclude necrotizing fasciitis (surgical emergency); drain abscess
– Mark the margin to track progression. Pain out of proportion is the necrotizing-fasciitis tell — call surgery.

Bacteremia

– Confirm: positive blood cultures ± no obvious source; assess for line/device/endocarditis source
– Plan: empiric then organism-directed antibiotics; identify + control the source (remove infected line/device); ID consult for S. aureus/fungemia/endocarditis evaluation; repeat cultures to document clearance + define duration
– S. aureus bacteremia needs ID involvement, source control, echo, and documented clearance — never just a short course.

Intra-abdominal infection

– Confirm: abdominal pain/tenderness/peritoneal signs, CT abdomen/pelvis (abscess, perforation, source)
– Plan: broad empiric antibiotics covering gram-negatives + anaerobes; SOURCE CONTROL is essential — surgery/IR drainage of abscess, repair of perforation; resuscitate; ICU if septic
– Source control is the cure; antibiotics are adjunctive. An undrained intra-abdominal collection won't resolve.

Cross-cutting

– Sepsis bundle (all comers): cultures before antibiotics, broad empiric antibiotics within 1 hour, lactate, IV fluids for hypoperfusion (e.g. ~30 mL/kg crystalloid), vasopressors (norepinephrine first-line) for fluid-refractory shock to MAP ≥65, reassess perfusion/lactate
– Trend: vitals/perfusion, lactate clearance, WBC/fever curve, culture results (de-escalate), source-control status, organ function
– Escalation triggers: septic shock (fluid-refractory hypotension) → vasopressors + ICU; necrotizing infection → emergent surgery; undrained source → urgent drainage; organ failure → ICU
– Discharge checklist: source identified + controlled + appropriate antibiotic regimen/duration (IV-to-oral plan); cultures followed up/de-escalated; hemodynamics + labs normalizing; follow-up (PCP/ID as relevant); return precautions (recurrent fever, worsening pain/erythema, lightheadedness, decreased urine)

104. Fever / Sepsis

/FeverSepsis · complete reference · resuscitate and find the source in parallel, source control where needed, tailor antibiotics to the focus · Full Card

Approach — Resuscitate and Find the Source in Parallel

• Fever and sepsis is the symptom where the workup and treatment run together: assess for sepsis or septic shock (qSOFA, organ dysfunction, lactate) and start the sepsis bundle (cultures before antibiotics, broad empiric antibiotics within 1 hour, fluids for hypoperfusion) while you hunt the source.

• Then differentiate by the likely focus — lung, urine, skin, blood, abdomen — and tailor antibiotics and source control to it.

• Key discriminators: cough, sputum, hypoxia, or an infiltrate → pneumonia; dysuria, frequency, flank pain, or pyuria → UTI or pyelonephritis; erythema, warmth, swelling, or a skin breach → cellulitis; no localizing source with positive blood cultures or an indwelling line or device → bacteremia; abdominal pain, tenderness, or peritoneal signs → intra-abdominal infection (needs source control).

Initial Symptoms / Data (all comers)

• Vitals (temperature, BP, HR, RR, SpO2) and perfusion and mentation.

• Blood cultures times two before antibiotics, lactate, CBC, BMP, UA with urine culture, and CXR; source-directed imaging (CT abdomen and pelvis for intra-abdominal infection, ultrasound for abscess); consider procalcitonin; a full skin, line, and device exam.

• Don't delay antibiotics to complete the workup in septic shock — and always look for a source needing drainage, because antibiotics alone won't cure an undrained abscess or an obstructed system.

Neg (don't-miss)

• Pt denies an undrained source or missed source control (abscess, an obstructed or infected urinary system, empyema, necrotizing infection — antibiotics alone fail) and a missed necrotizing fasciitis (pain out of proportion, rapid progression, crepitus → a surgical emergency).

• Pt denies a missed neutropenic fever, meningitis, or endocarditis and delaying antibiotics in septic shock.

• Pt denies a missed non-infectious fever (VTE, drug fever).

DDx

Pneumonia · UTI or pyelonephritis · cellulitis · bacteremia · intra-abdominal infection · (also: meningitis, endocarditis, line infection, C. difficile, necrotizing soft-tissue infection, non-infectious fever)

Plan — by Source

CONSULT (as relevant): Infectious Disease (complex or resistant infection, bacteremia, endocarditis) · Surgery or IR (source control — drainage, debridement) · ICU (septic shock, organ dysfunction) · Urology (obstructed infected system)

• Pneumonia — confirm: cough, sputum, or hypoxia, a focal exam, and an infiltrate on CXR; sputum and blood cultures. Plan: empiric antibiotics per setting and severity (CAP: ceftriaxone plus azithromycin or a respiratory fluoroquinolone; add MRSA or Pseudomonas coverage for healthcare-associated or severe disease per risk); O2; a severity score (CURB-65 or PSI) for disposition; de-escalate by cultures.

• UTI / Pyelonephritis — confirm: dysuria, frequency, or flank pain, with pyuria and a positive urine culture; imaging if obstruction or abscess is suspected. Plan: empiric antibiotics per severity and local resistance (e.g. ceftriaxone for pyelonephritis; tailor by culture); an obstructed infected system (stone, hydronephrosis) → urgent urology or IR decompression (source control); hydration.

• Cellulitis — confirm: erythema, warmth, swelling, and tenderness with a skin breach or portal; mark the border. Plan: antibiotics covering streptococci with possible Staph coverage (MRSA coverage per risk or purulence — e.g. cephalexin, or vancomycin if MRSA or severe); elevate; treat the portal of entry; if pain out of proportion, rapid spread, crepitus, or systemic toxicity → exclude necrotizing fasciitis (a surgical emergency); drain an abscess.

• Bacteremia — confirm: positive blood cultures with or without an obvious source; assess for a line, device, or endocarditis source. Plan: empiric then organism-directed antibiotics; identify and control the source (remove an infected line or device); an ID consult for S. aureus, fungemia, or endocarditis evaluation; repeat cultures to document clearance and define duration.

• Intra-abdominal infection — confirm: abdominal pain, tenderness, or peritoneal signs, with a CT abdomen and pelvis (abscess, perforation, source). Plan: broad empiric antibiotics covering gram-negatives and anaerobes; source control is essential — surgical or IR drainage of an abscess, repair of a perforation; resuscitate; ICU if septic.

• Sepsis bundle (all comers): cultures before antibiotics, broad empiric antibiotics within 1 hour, lactate, IV fluids for hypoperfusion (e.g. about 30 mL/kg crystalloid), vasopressors (norepinephrine first-line) for fluid-refractory shock to a MAP of at least 65, and reassess perfusion and lactate.

• Cross-cutting — trend: vitals and perfusion, lactate clearance, the WBC and fever curve, culture results (de-escalate), source-control status, and organ function.

• Escalation triggers: septic shock (fluid-refractory hypotension) → vasopressors and ICU; necrotizing infection → emergent surgery; an undrained source → urgent drainage; organ failure → ICU.

• Discharge checklist: the source identified and controlled with an appropriate antibiotic regimen and duration (an IV-to-oral plan); cultures followed up and de-escalated; hemodynamics and labs normalizing; follow-up (PCP or ID as relevant); return precautions for recurrent fever, worsening pain or erythema, lightheadedness, or decreased urine.

Red Flags

• Fluid-refractory hypotension or a rising lactate → septic shock; vasopressors and ICU.

• Pain out of proportion, rapid spread, or crepitus → necrotizing fasciitis; emergent surgery.

• An obstructed, infected urinary system → a urologic emergency; antibiotics won't work without decompression.

• An undrained abscess or collection → antibiotics alone fail; source control is the cure.

• S. aureus or fungus in the blood → never a short empiric course; ID, source control, echo, and documented clearance.

Senior IM Resident Pearls

• Treat and work up at once. Cultures, then antibiotics within the hour, fluids for hypoperfusion — don't wait for the source to declare itself in shock.

• Source control is half the cure. An undrained abscess, an obstructed kidney, or an infected line won't respond to antibiotics alone.

• Pain out of proportion is the necrotizing tell. When the pain outstrips the skin findings, call surgery.

• S. aureus bacteremia is a different animal. It needs ID, an echo, source control, and documented clearance — never a casual short course.

• Norepinephrine is the first pressor. After adequate fluids, it's the agent for septic shock to a MAP of 65.

• Mark the cellulitis border. It's the simplest way to know whether you're winning or losing.

• Common mistake: giving broad antibiotics and feeling done — while the abscess, the obstructed system, or the infected line that actually drives the sepsis goes uncontrolled.

Symptom-Based DDx & Plans — Geriatric / General

105. Weakness / Functional Decline

/WeaknessFunctionalDecline · differentiate generalized vs focal weakness first, then treat the cause · infection · dehydration · anemia · stroke · malnutrition · progressive dementia · Super Compact

Approach — separate FOCAL from GENERALIZED weakness, then differentiate. The first fork is whether this is true focal neurologic weakness (a stroke/neuro lesion — urgent) or generalized weakness/"functional decline", which in the inpatient/elderly population is usually a systemic problem — infection, dehydration, anemia, malnutrition, or deconditioning on a background of frailty/dementia. "Weakness" is a vague chief complaint that is most often the presenting face of an acute medical illness in an older adult.

Key discriminators: FOCAL deficit / sudden / unilateral → stroke (don't miss) · fever/source/leukocytosis → infection · poor intake/orthostasis/dry mucous membranes/high BUN:Cr → dehydration · pallor/fatigue/low hemoglobin ± bleeding source → anemia · weight loss/low intake/low albumin/cachexia → malnutrition · gradual chronic cognitive + functional decline, baseline-confirmed → progressive dementia (exclude acute causes first)

Initial Sx/Data (all comers): vitals + orthostatics, focused neuro exam (focal vs symmetric), functional/ADL assessment; CBC (anemia), BMP (electrolytes, BUN:Cr, glucose), UA/cultures, TSH, B12; consider troponin/ECG (atypical ACS), CT head if focal; nutrition/albumin/prealbumin; medication review; collateral history + baseline function · (weakness in an older adult is a symptom to be worked up, not a diagnosis — the dangerous causes hide behind it: occult infection, atypical ACS, stroke, GI bleed causing anemia)

Neg (don't-miss): denies missed stroke (focal deficit) · denies missed occult infection/sepsis (common, may lack classic signs) · denies missed atypical ACS (weakness as anginal equivalent — ECG/troponin) · denies missed symptomatic anemia / GI bleed source · denies missed electrolyte derangement · denies labeling "just deconditioning/dementia" without excluding acute causes

DDx: infection · dehydration · anemia · stroke · malnutrition · progressive dementia · (also: atypical ACS, electrolyte abnormalities, medication effect, depression, hypothyroidism, deconditioning)

Plan — by Diagnosis

CONSULT (as relevant): Neurology (focal deficit/stroke) · PT/OT (functional decline — essential) · Geriatrics (frailty, multifactorial) · Nutrition (malnutrition) · Social work/Case management (disposition)

Infection

– Confirm: fever/leukocytosis/localizing source (or occult — UTI/pneumonia common in elderly); cultures, UA, CXR
– Plan: identify source + empiric antibiotics per source/severity; sepsis pathway if criteria met; weakness/decline often resolves as infection is treated
– Occult infection is the leading reversible cause of functional decline in the elderly — look even without classic signs.

Dehydration

– Confirm: poor intake, orthostasis, dry mucous membranes, elevated BUN:Cr, prerenal indices
– Plan: IV fluid resuscitation/rehydration, address the cause of poor intake (nausea, dysphagia, access), monitor electrolytes + renal function; encourage/assist oral intake
– Cheap and reversible — but find why intake dropped (it's often a clue to another problem).

Anemia

– Confirm: pallor/fatigue, low hemoglobin ± bleeding source; iron studies/retic/smear; check stool/GI source
– Plan: identify the type/cause (iron-deficiency → GI source workup; treat the cause); transfuse for symptomatic/severe anemia (restrictive threshold ~7, higher if cardiac); iron/B12 repletion as indicated
– New iron-deficiency anemia in an older adult is a GI cancer workup until proven otherwise.

Stroke

– Confirm: focal deficit, sudden/unilateral weakness; urgent CT head, last-known-well
– Plan: activate stroke pathway/neurology; ischemic in window → thrombolysis/thrombectomy eligibility; hemorrhage → BP control + neurosurgery; aspiration precautions; rehab planning
– Don't let "generalized weakness" obscure a focal deficit — examine for asymmetry deliberately.

Malnutrition

– Confirm: weight loss, low intake, low albumin/prealbumin, cachexia; nutrition assessment
– Plan: nutritional support (oral supplements, dietitian, address dysphagia/swallow eval, treat reversible causes of poor intake), monitor for refeeding syndrome when repleting; investigate underlying cause (malignancy, depression)
– When repleting a severely malnourished patient, watch electrolytes for refeeding syndrome (low phosphate/K/Mg).

Progressive dementia

– Confirm: gradual chronic cognitive + functional decline, baseline-confirmed — exclude acute reversible causes first
– Plan: exclude delirium/acute illness; supportive + functional optimization (PT/OT), caregiver support, safety, goals-of-care discussion; avoid over-medication; disposition planning
– Functional decline attributed to dementia still deserves a workup for the superimposed acute illness that triggered the admission.

Cross-cutting

– PT/OT is central to almost every cause — assess function early, mobilize, prevent further deconditioning, plan disposition/rehab
– Trend: functional status/ADLs, the corrected driver, vitals/labs, response to treatment
– Escalation triggers: stroke → emergent neuro/reperfusion; sepsis → sepsis pathway + ICU if unstable; symptomatic severe anemia/active bleed → transfusion + source control; atypical ACS → cardiology
– Discharge checklist: acute reversible causes excluded/treated + function optimized; safe disposition (home with services vs rehab vs SNF) per functional assessment; nutrition/PT/OT follow-up; medication review/deprescribing; return precautions (focal weakness, fever, falls, decreased intake, worsening function)

105. Weakness / Functional Decline

/WeaknessFunctionalDecline · complete reference · separate focal from generalized, work up the reversible drivers, optimize function and disposition · Full Card

Approach — Focal vs Generalized, Then Differentiate

• The first fork is whether this is true focal neurologic weakness (a stroke or neuro lesion — urgent) or generalized weakness or "functional decline," which in the inpatient and elderly population is usually a systemic problem — infection, dehydration, anemia, malnutrition, or deconditioning on a background of frailty or dementia.

• "Weakness" is a vague chief complaint that is most often the presenting face of an acute medical illness in an older adult.

• Key discriminators: a focal, sudden, or unilateral deficit → stroke (don't miss); fever, a source, or leukocytosis → infection; poor intake, orthostasis, dry mucous membranes, or a high BUN-to-creatinine ratio → dehydration; pallor, fatigue, a low hemoglobin, or a bleeding source → anemia; weight loss, low intake, a low albumin, or cachexia → malnutrition; a gradual, chronic cognitive and functional decline confirmed against baseline → progressive dementia (exclude acute causes first).

Initial Symptoms / Data (all comers)

• Vitals with orthostatics, a focused neuro exam (focal versus symmetric), and a functional and ADL assessment.

• CBC (anemia), BMP (electrolytes, BUN-to-creatinine ratio, glucose), UA and cultures, TSH, and B12; consider troponin and ECG (atypical ACS), and a CT head if focal; nutrition assessment with albumin and prealbumin; a medication review; collateral history and baseline function.

• Weakness in an older adult is a symptom to be worked up, not a diagnosis — the dangerous causes hide behind it: occult infection, atypical ACS, stroke, and a GI bleed causing anemia.

Neg (don't-miss)

• Pt denies a missed stroke (focal deficit) and a missed occult infection or sepsis (common, may lack classic signs).

• Pt denies a missed atypical ACS (weakness as an anginal equivalent — ECG and troponin) and a missed symptomatic anemia or GI bleed source.

• Pt denies a missed electrolyte derangement and labeling it "just deconditioning" or "dementia" without excluding acute causes.

DDx

Infection · dehydration · anemia · stroke · malnutrition · progressive dementia · (also: atypical ACS, electrolyte abnormalities, medication effect, depression, hypothyroidism, deconditioning)

Plan — by Diagnosis

CONSULT (as relevant): Neurology (focal deficit or stroke) · PT/OT (functional decline — essential) · Geriatrics (frailty, multifactorial decline) · Nutrition (malnutrition) · Social work or Case management (disposition)

• Infection — confirm: fever, leukocytosis, or a localizing source (or occult — UTI and pneumonia are common in the elderly); cultures, UA, CXR. Plan: identify the source and give empiric antibiotics per source and severity; the sepsis pathway if criteria are met; weakness and decline often resolve as the infection is treated.

• Dehydration — confirm: poor intake, orthostasis, dry mucous membranes, an elevated BUN-to-creatinine ratio, and prerenal indices. Plan: IV fluid resuscitation and rehydration, address the cause of poor intake (nausea, dysphagia, access), and monitor electrolytes and renal function; encourage and assist oral intake.

• Anemia — confirm: pallor and fatigue with a low hemoglobin and a possible bleeding source; iron studies, reticulocyte count, and smear; check stool and a GI source. Plan: identify the type and cause (iron deficiency → a GI source workup; treat the cause); transfuse for symptomatic or severe anemia (a restrictive threshold around 7, higher if cardiac); iron or B12 repletion as indicated.

• Stroke — confirm: a focal deficit and sudden or unilateral weakness; an urgent CT head, last-known-well time. Plan: activate the stroke pathway and neurology; ischemic stroke within the window → thrombolysis and thrombectomy eligibility; hemorrhage → BP control and neurosurgery; aspiration precautions; rehab planning.

• Malnutrition — confirm: weight loss, low intake, a low albumin and prealbumin, and cachexia; a nutrition assessment. Plan: nutritional support (oral supplements, a dietitian, address dysphagia with a swallow evaluation, treat reversible causes of poor intake), and monitor for refeeding syndrome when repleting; investigate the underlying cause (malignancy, depression).

• Progressive dementia — confirm: a gradual, chronic cognitive and functional decline confirmed against baseline — exclude acute reversible causes first. Plan: exclude delirium and acute illness; supportive care and functional optimization (PT/OT), caregiver support, safety, and a goals-of-care discussion; avoid over-medication; disposition planning.

• Cross-cutting: PT/OT is central to almost every cause — assess function early, mobilize, prevent further deconditioning, and plan disposition or rehab.

• Trend: functional status and ADLs, the corrected driver, vitals and labs, and the response to treatment.

• Escalation triggers: stroke → emergent neurology and reperfusion; sepsis → the sepsis pathway and ICU if unstable; symptomatic severe anemia or an active bleed → transfusion and source control; atypical ACS → cardiology.

• Discharge checklist: acute reversible causes excluded or treated and function optimized; a safe disposition (home with services versus rehab versus SNF) per the functional assessment; nutrition and PT/OT follow-up; medication review and deprescribing; return precautions for focal weakness, fever, falls, decreased intake, or worsening function.

Red Flags

• A focal or unilateral deficit hidden in "generalized weakness" → stroke; examine deliberately for asymmetry.

• Weakness with no obvious cause in an older adult → occult infection or atypical ACS; check cultures, ECG, and troponin.

• New iron-deficiency anemia → a GI cancer workup until proven otherwise.

• Refeeding a severely malnourished patient → watch phosphate, potassium, and magnesium for refeeding syndrome.

• Rapid functional decline → don't attribute it to dementia without excluding the acute trigger.

Senior IM Resident Pearls

• "Weakness" is a workup, not a diagnosis. In an older adult it's usually the face of an acute medical illness — find it.

• Examine for focality on purpose. A subtle hemiparesis hides easily behind a complaint of feeling weak all over.

• Occult infection leads the reversible causes. UTI and pneumonia present as decline without fever or classic signs in the frail.

• New iron-deficiency anemia means look at the gut. Especially in older adults, it's a colon cancer screen until proven otherwise.

• Watch refeeding when repleting. Severe malnutrition plus aggressive feeding drops phosphate, potassium, and magnesium dangerously.

• PT/OT is treatment. Early mobilization and functional assessment shape both recovery and a safe disposition.

• Common mistake: admitting "deconditioning" and never finding the occult infection, anemia, or atypical ACS that actually caused the decline.

Symptom-Based DDx & Plans — Geriatric / General

106. Fall

/Fall · differentiate "did they pass out?" (syncope) from a true mechanical fall, screen the cause + the injury · mechanical · syncope · orthostasis · infection · medication effect · Super Compact

Approach — two questions: WHY did they fall, and WHAT did they injure? First decide whether there was loss of consciousness (→ work up as syncope — cardiac/neuro/vascular) or a true mechanical fall (trip/slip with a clear environmental cause and no LOC). Then differentiate the contributing cause — orthostasis, infection, medication effect, gait/balance/vision, environment — because falls are usually multifactorial in the elderly. Always evaluate the injury (especially head injury on anticoagulation, hip fracture).

Key discriminators: clear trip/slip, environmental, no LOC → mechanical · LOC/witnessed collapse → syncope (cardiac/arrhythmia/neuro — work up separately) · postural lightheadedness, positional drop in BP → orthostasis · fever/source → infection (falls as atypical presentation) · new/culprit sedating, antihypertensive, hypoglycemic, or anticholinergic drug → medication effect · gait/balance/vision/cognitive impairment + hazards → multifactorial frailty

Initial Sx/Data (all comers): circumstances + LOC history + witnesses, orthostatic vitals, gait/balance assessment, full medication review; injury survey: head (CT head if anticoagulated/LOC/head strike/focal signs), hip/long-bone (X-ray if pain/can't bear weight), C-spine if indicated; ECG, BMP/glucose, CBC, UA; consider troponin if syncope-type · (the two things you cannot miss are an intracranial bleed — especially in an anticoagulated patient even with a "minor" head strike — and a cardiac/arrhythmic cause masquerading as a mechanical fall)

Neg (don't-miss): denies missed intracranial hemorrhage (anticoagulated + head strike → CT head, even if "minor") · denies missed occult fracture (hip/pelvis — can't bear weight) · denies syncope/arrhythmia mislabeled as mechanical (cardiac syncope is high-risk) · denies missed cervical spine injury · denies missed infection/medication trigger · denies discharging without a falls-prevention plan

DDx (cause): mechanical fall · syncope · orthostatic hypotension · infection · medication effect · (also: arrhythmia, neurologic — stroke/seizure/Parkinsonism, vision/gait/balance disorder, environmental hazards — usually multifactorial)

Plan — by Cause

CONSULT (as relevant): PT/OT (gait/balance, falls prevention — essential) · Orthopedics (fracture) · Neurosurgery (intracranial bleed) · Cardiology (syncope/arrhythmia) · Geriatrics (multifactorial)

Mechanical fall

– Confirm: clear trip/slip, environmental cause, no LOC; assess injury
– Plan: treat injuries; PT/OT gait + balance assessment; address environmental hazards + assistive devices; vision/footwear; falls-prevention plan; review meds contributing to instability
– Even a "simple" mechanical fall earns a falls-prevention workup — they recur and predict morbidity.

Syncope

– Confirm: LOC/collapse; ECG, telemetry, troponin; assess cardiac (arrhythmia/structural) vs neuro vs vasovagal
– Plan: work up per the syncope pathway — cardiac syncope is high-risk (telemetry/admission, echo, rhythm monitoring); treat the cause; see the syncope card
– A fall with LOC is syncope until proven otherwise — and cardiac syncope can be the warning before sudden death.

Orthostatic hypotension

– Confirm: positional symptoms + documented orthostatic BP drop; assess volume + meds
– Plan: rehydrate/treat hypovolemia; review + reduce offending meds (antihypertensives, diuretics, alpha-blockers, vasodilators); slow positional changes; compression stockings; address autonomic causes
– Deprescribing the offending antihypertensive is often the single most effective intervention.

Infection

– Confirm: fever/source/leukocytosis (falls can be an atypical infection presentation in elderly); UA, cultures, CXR
– Plan: identify source + treat infection per source/severity; instability often improves as infection resolves
– A new fall in an elderly patient can be the only sign of a UTI or pneumonia — check.

Medication effect

– Confirm: new/culprit drug (sedatives, benzos, antihypertensives, hypoglycemics, anticholinergics), polypharmacy
– Plan: deprescribe/adjust the offending agent(s); review the full list for fall-risk-increasing drugs; renal dosing; correct hypoglycemia if implicated
– Polypharmacy and fall-risk-increasing drugs are among the most modifiable causes — review the list every admission.

Cross-cutting

– Injury survey is mandatory: CT head (low threshold, especially anticoagulated), fracture evaluation (hip/pelvis/wrist), C-spine; reverse/hold anticoagulation if intracranial hemorrhage
– Falls are multifactorial: address all contributors (gait, vision, meds, orthostasis, environment, cognition) — PT/OT central
– Trend: injury status, the corrected cause(s), orthostatics, functional/gait status
– Escalation triggers: intracranial hemorrhage → neurosurgery + reversal + ICU; unstable fracture → orthopedics; cardiac syncope/arrhythmia → cardiology/telemetry; hemodynamic instability → ICU
– Discharge checklist: injuries addressed + cause(s) identified + multifactorial falls-prevention plan (PT/OT, meds, home safety, vision); safe disposition; anticoagulation reassessed; return precautions (head injury symptoms, worsening pain/inability to bear weight, recurrent falls, syncope)

106. Fall

/Fall · complete reference · distinguish syncope from mechanical, survey the injury (CT head if anticoagulated), address the multifactorial cause · Full Card

Approach — Why Did They Fall, and What Did They Injure?

• First decide whether there was loss of consciousness (→ work up as syncope — cardiac, neuro, vascular) or a true mechanical fall (a trip or slip with a clear environmental cause and no LOC).

• Then differentiate the contributing cause — orthostasis, infection, medication effect, gait, balance, or vision impairment, and environment — because falls are usually multifactorial in the elderly.

• Always evaluate the injury, especially a head injury on anticoagulation and a hip fracture.

• Key discriminators: a clear trip or slip, environmental, no LOC → mechanical; LOC or a witnessed collapse → syncope (cardiac, arrhythmia, neuro — work up separately); postural lightheadedness with a positional BP drop → orthostasis; fever or a source → infection (falls as an atypical presentation); a new or culprit sedating, antihypertensive, hypoglycemic, or anticholinergic drug → medication effect; gait, balance, vision, or cognitive impairment with hazards → multifactorial frailty.

Initial Symptoms / Data (all comers)

• The circumstances, LOC history, and witnesses; orthostatic vitals; a gait and balance assessment; and a full medication review.

• An injury survey: head (CT head if anticoagulated, LOC, a head strike, or focal signs), hip and long-bone (X-ray if pain or unable to bear weight), and C-spine if indicated; ECG, BMP and glucose, CBC, and UA; consider troponin if syncope-type.

• The two things you cannot miss are an intracranial bleed — especially in an anticoagulated patient even with a "minor" head strike — and a cardiac or arrhythmic cause masquerading as a mechanical fall.

Neg (don't-miss)

• Pt denies a missed intracranial hemorrhage (anticoagulated with a head strike → CT head, even if "minor") and a missed occult fracture (hip or pelvis — unable to bear weight).

• Pt denies syncope or arrhythmia mislabeled as mechanical (cardiac syncope is high-risk) and a missed cervical spine injury.

• Pt denies a missed infection or medication trigger and discharging without a falls-prevention plan.

DDx (cause)

Mechanical fall · syncope · orthostatic hypotension · infection · medication effect · (also: arrhythmia, neurologic causes — stroke, seizure, Parkinsonism, a vision, gait, or balance disorder, environmental hazards — usually multifactorial)

Plan — by Cause

CONSULT (as relevant): PT/OT (gait and balance, falls prevention — essential) · Orthopedics (fracture) · Neurosurgery (intracranial bleed) · Cardiology (syncope or arrhythmia) · Geriatrics (multifactorial)

• Mechanical fall — confirm: a clear trip or slip, an environmental cause, and no LOC; assess the injury. Plan: treat injuries; a PT/OT gait and balance assessment; address environmental hazards and assistive devices; vision and footwear; a falls-prevention plan; review medications contributing to instability.

• Syncope — confirm: LOC or collapse; ECG, telemetry, troponin; assess cardiac (arrhythmia, structural) versus neuro versus vasovagal causes. Plan: work up per the syncope pathway — cardiac syncope is high-risk (telemetry or admission, echo, rhythm monitoring); treat the cause (see the syncope card).

• Orthostatic hypotension — confirm: positional symptoms with a documented orthostatic BP drop; assess volume and medications. Plan: rehydrate and treat hypovolemia; review and reduce offending medications (antihypertensives, diuretics, alpha-blockers, vasodilators); slow positional changes; compression stockings; address autonomic causes.

• Infection — confirm: fever, a source, or leukocytosis (falls can be an atypical infection presentation in the elderly); UA, cultures, CXR. Plan: identify the source and treat the infection per source and severity; instability often improves as the infection resolves.

• Medication effect — confirm: a new or culprit drug (sedatives, benzodiazepines, antihypertensives, hypoglycemics, anticholinergics) or polypharmacy. Plan: deprescribe or adjust the offending agents; review the full list for fall-risk-increasing drugs; renal dosing; correct hypoglycemia if implicated.

• Cross-cutting — injury survey is mandatory: a CT head (low threshold, especially if anticoagulated), a fracture evaluation (hip, pelvis, wrist), and C-spine; reverse or hold anticoagulation if there is an intracranial hemorrhage.

• Falls are multifactorial: address all contributors (gait, vision, medications, orthostasis, environment, cognition) — PT/OT is central.

• Trend: injury status, the corrected causes, orthostatics, and functional and gait status.

• Escalation triggers: intracranial hemorrhage → neurosurgery, reversal, and ICU; an unstable fracture → orthopedics; cardiac syncope or arrhythmia → cardiology and telemetry; hemodynamic instability → ICU.

• Discharge checklist: injuries addressed, the causes identified, and a multifactorial falls-prevention plan (PT/OT, medications, home safety, vision); a safe disposition; anticoagulation reassessed; return precautions for head injury symptoms, worsening pain or inability to bear weight, recurrent falls, or syncope.

Red Flags

• A head strike on anticoagulation → intracranial hemorrhage even when "minor"; low threshold for CT head and reversal.

• Loss of consciousness → syncope, not a simple fall; cardiac syncope can precede sudden death.

• Inability to bear weight → an occult hip or pelvic fracture; image it.

• Neck pain or a high-energy mechanism → cervical spine injury; immobilize and image.

• A new fall with no clear mechanism in an elderly patient → occult infection, arrhythmia, or medication effect.

Senior IM Resident Pearls

• Ask about LOC first. It splits a benign mechanical fall from a potentially lethal syncope and changes the entire workup.

• Anticoagulated head strike gets a CT. A delayed intracranial bleed can be catastrophic even after a trivial-seeming fall.

• Falls are multifactorial. Rarely one cause — address gait, vision, meds, orthostasis, environment, and cognition together.

• Deprescribing is high-yield. Cutting the offending antihypertensive or sedative is often the single best intervention.

• A fall can be the only sign of infection. Check for a UTI or pneumonia in the elderly patient who suddenly starts falling.

• PT/OT before discharge. A falls-prevention assessment reduces the recurrence that predicts real morbidity.

• Common mistake: documenting "mechanical fall" and discharging without working up the syncope, the injury, or the modifiable multifactorial causes.

Symptom-Based DDx & Plans — Cardiovascular

107. Syncope / Near-Syncope

/Syncope · differentiate cardiac (high-risk) from reflex/orthostatic, and never miss a bleed or PE · orthostatic · arrhythmia · vasovagal · GI bleed · PE · Super Compact

Approach — the central job is to separate high-risk (cardiac) syncope from benign reflex syncope, and to catch the dangerous mimics. Syncope is transient LOC from global cerebral hypoperfusion. The high-stakes question: is this cardiac (arrhythmia/structural — risk of sudden death) or reflex/orthostatic (benign)? — driven by ECG, the circumstances, and red-flag features (exertional, no prodrome, cardiac history, abnormal ECG). And always exclude occult blood loss (GI bleed) and PE, which present as syncope.

Key discriminators: exertional/no prodrome/palpitations/cardiac hx/abnormal ECG/family history sudden death → cardiac (high-risk) · prolonged standing/triggers (pain, micturition)/prodrome (warmth, nausea) → vasovagal · postural symptoms + orthostatic BP drop → orthostatic · melena/hematemesis/anemia/abdominal → GI bleed · dyspnea/pleuritic/hypoxia/VTE risk → PE

Initial Sx/Data (all comers): circumstances/prodrome/witnesses, orthostatic vitals, ECG (every patient), telemetry if cardiac suspected; CBC (anemia/bleed), BMP, glucose; rectal exam/stool for blood; troponin + echo if cardiac; D-dimer/CTA if PE suspected; pregnancy test where relevant; risk stratification (e.g. Canadian Syncope Risk Score) · (the ECG plus the presence or absence of red flags drives disposition — exertional syncope, syncope without warning, and an abnormal ECG are cardiac until proven otherwise and warrant monitoring/admission)

Neg (don't-miss): denies missed cardiac syncope (exertional, no prodrome, abnormal ECG, structural disease — sudden death risk) · denies missed GI bleed (syncope from blood loss — check Hgb + stool) · denies missed PE · denies missed aortic stenosis / outflow obstruction (exertional syncope + murmur) · denies missed subarachnoid hemorrhage (if headache) · denies discharging high-risk syncope

DDx: orthostatic hypotension · arrhythmia · vasovagal (reflex) · GI bleed · pulmonary embolism · (also: aortic stenosis/HOCM, structural heart disease, carotid sinus hypersensitivity, seizure mimic, medication-induced)

Plan — by Diagnosis

CONSULT (as relevant): Cardiology (arrhythmia, structural, high-risk syncope) · GI (GI bleed) · ICU/Telemetry (high-risk, unstable)

Orthostatic hypotension

– Confirm: postural symptoms + documented orthostatic BP drop; assess volume/meds/autonomic
– Plan: rehydrate/treat hypovolemia, review + reduce offending meds (antihypertensives/diuretics/alpha-blockers), slow position changes, compression stockings; treat underlying cause (bleeding, dehydration, autonomic)
– Confirm orthostasis is the cause, but don't stop there — orthostasis from a GI bleed is still a GI bleed.

Arrhythmia

– Confirm: palpitations/abnormal ECG/structural disease; telemetry, ECG, echo; brady (heart block/sinus node) vs tachy (VT/SVT)
– Plan: continuous monitoring; treat the rhythm — symptomatic bradycardia/high-grade block → pacing; VT/structural → cardiology, antiarrhythmic/ICD evaluation; SVT per rhythm; admit high-risk
– Arrhythmic syncope is the one that kills next time — monitored bed, echo, and cardiology, not discharge.

Vasovagal (reflex)

– Confirm: typical trigger + prodrome (warmth, nausea, diaphoresis), benign exam/ECG — a clinical diagnosis
– Plan: reassurance + education, trigger avoidance, counterpressure maneuvers, hydration/salt; usually no further cardiac workup if classic + low-risk
– A classic vasovagal story with a normal ECG in a young low-risk patient needs little more than education.

GI bleed

– Confirm: melena/hematemesis, anemia/Hgb drop, positive stool; hemodynamics
– Plan: resuscitate (IV access ×2, fluids, transfuse per hemodynamics/Hgb), PPI for upper source, type + cross, hold anticoagulation/reverse if needed, GI for endoscopy; see the GI bleeding card
– Syncope can be the first sign of a brisk GI bleed before the obvious blood appears — check the Hgb and the rectum.

Pulmonary embolism

– Confirm: dyspnea/pleuritic/hypoxia/tachycardia/VTE risk; D-dimer/CTA; RV strain
– Plan: anticoagulation; massive/unstable → thrombolysis + ICU; O2; see the dyspnea card's PE approach
– Syncope can be the presenting feature of a large PE — consider it when the story or vitals fit.

Cross-cutting

– Risk-stratify disposition: high-risk features (exertional, no prodrome, abnormal ECG, structural/cardiac history, family history sudden death, anemia) → admit/monitor; low-risk classic reflex → discharge with follow-up
– Trend: telemetry/rhythm, orthostatics, Hgb (if bleed), response to treatment
– Escalation triggers: unstable arrhythmia → ACLS/pacing/cardiology + ICU; massive GI bleed → resuscitation + urgent endoscopy/ICU; massive PE → thrombolysis; outflow obstruction with instability → cardiology/surgery
– Discharge checklist: high-risk causes excluded + cause identified/treated; appropriate disposition (monitored vs discharge); cardiology/GI follow-up as relevant; driving/activity counseling; return precautions (recurrent syncope, chest pain, palpitations, melena, dyspnea)

107. Syncope / Near-Syncope

/Syncope · complete reference · separate cardiac (high-risk) from reflex/orthostatic, exclude GI bleed and PE, risk-stratify disposition · Full Card

Approach — Cardiac (High-Risk) vs Reflex, and the Dangerous Mimics

• Syncope is transient loss of consciousness from global cerebral hypoperfusion. The high-stakes question: is this cardiac (arrhythmia or structural — a risk of sudden death) or reflex or orthostatic (benign)? — driven by the ECG, the circumstances, and red-flag features (exertional, no prodrome, cardiac history, an abnormal ECG).

• And always exclude occult blood loss (GI bleed) and PE, which present as syncope.

• Key discriminators: exertional onset, no prodrome, palpitations, a cardiac history, an abnormal ECG, or a family history of sudden death → cardiac (high-risk); prolonged standing or triggers (pain, micturition) with a prodrome (warmth, nausea) → vasovagal; postural symptoms with an orthostatic BP drop → orthostatic; melena, hematemesis, anemia, or abdominal symptoms → GI bleed; dyspnea, pleuritic pain, hypoxia, or VTE risk → PE.

Initial Symptoms / Data (all comers)

• The circumstances, prodrome, and witnesses; orthostatic vitals; an ECG (every patient); and telemetry if cardiac is suspected.

• CBC (anemia or bleed), BMP, and glucose; a rectal exam and stool for blood; troponin and echo if cardiac; a D-dimer or CTA if PE is suspected; a pregnancy test where relevant; risk stratification (e.g. the Canadian Syncope Risk Score).

• The ECG plus the presence or absence of red flags drives disposition — exertional syncope, syncope without warning, and an abnormal ECG are cardiac until proven otherwise and warrant monitoring or admission.

Neg (don't-miss)

• Pt denies a missed cardiac syncope (exertional, no prodrome, an abnormal ECG, structural disease — sudden death risk) and a missed GI bleed (syncope from blood loss — check hemoglobin and stool).

• Pt denies a missed PE and a missed aortic stenosis or outflow obstruction (exertional syncope with a murmur).

• Pt denies a missed subarachnoid hemorrhage (if there is a headache) and discharging high-risk syncope.

DDx

Orthostatic hypotension · arrhythmia · vasovagal (reflex) · GI bleed · pulmonary embolism · (also: aortic stenosis or HOCM, structural heart disease, carotid sinus hypersensitivity, a seizure mimic, medication-induced syncope)

Plan — by Diagnosis

CONSULT (as relevant): Cardiology (arrhythmia, structural disease, high-risk syncope) · GI (GI bleed) · ICU or Telemetry (high-risk, unstable)

• Orthostatic hypotension — confirm: postural symptoms with a documented orthostatic BP drop; assess volume, medications, and autonomic function. Plan: rehydrate and treat hypovolemia, review and reduce offending medications (antihypertensives, diuretics, alpha-blockers), slow position changes, compression stockings; treat the underlying cause (bleeding, dehydration, autonomic dysfunction).

• Arrhythmia — confirm: palpitations, an abnormal ECG, or structural disease; telemetry, ECG, echo; bradycardia (heart block, sinus node disease) versus tachycardia (VT, SVT). Plan: continuous monitoring; treat the rhythm — symptomatic bradycardia or high-grade block → pacing; VT or structural disease → cardiology, antiarrhythmic or ICD evaluation; SVT per rhythm; admit high-risk patients.

• Vasovagal (reflex) — confirm: a typical trigger with a prodrome (warmth, nausea, diaphoresis) and a benign exam and ECG — a clinical diagnosis. Plan: reassurance and education, trigger avoidance, counterpressure maneuvers, and hydration and salt; usually no further cardiac workup if classic and low-risk.

• GI bleed — confirm: melena or hematemesis, anemia or a hemoglobin drop, and positive stool; hemodynamics. Plan: resuscitate (two large-bore IVs, fluids, transfuse per hemodynamics and hemoglobin), a PPI for an upper source, type and cross, hold or reverse anticoagulation if needed, and GI for endoscopy (see the GI bleeding card).

• Pulmonary embolism — confirm: dyspnea, pleuritic pain, hypoxia, tachycardia, or VTE risk; a D-dimer or CTA; RV strain. Plan: anticoagulation; a massive or unstable PE → thrombolysis and ICU; O2 (see the dyspnea card's PE approach).

• Cross-cutting — risk-stratify disposition: high-risk features (exertional, no prodrome, an abnormal ECG, a structural or cardiac history, a family history of sudden death, anemia) → admit and monitor; a low-risk classic reflex story → discharge with follow-up.

• Trend: telemetry and rhythm, orthostatics, hemoglobin (if a bleed), and the response to treatment.

• Escalation triggers: an unstable arrhythmia → ACLS, pacing, cardiology, and ICU; a massive GI bleed → resuscitation, urgent endoscopy, and ICU; massive PE → thrombolysis; outflow obstruction with instability → cardiology or surgery.

• Discharge checklist: high-risk causes excluded and the cause identified and treated; an appropriate disposition (monitored versus discharge); cardiology or GI follow-up as relevant; driving and activity counseling; return precautions for recurrent syncope, chest pain, palpitations, melena, or dyspnea.

Red Flags

• Exertional syncope, no prodrome, or an abnormal ECG → cardiac syncope; monitor and admit, don't discharge.

• Exertional syncope with a systolic murmur → aortic stenosis or outflow obstruction; echo and cardiology.

• Syncope with anemia or melena → a GI bleed; resuscitate and scope.

• Syncope with dyspnea, hypoxia, or VTE risk → pulmonary embolism.

• A family history of sudden death → an inherited arrhythmia or cardiomyopathy; cardiology evaluation.

Senior IM Resident Pearls

• The ECG and red flags drive disposition. Exertional syncope, no warning, or an abnormal ECG means a monitored bed, not a discharge.

• Cardiac syncope kills next time. The danger isn't the faint — it's the arrhythmia or obstruction that recurs as sudden death.

• Syncope can be a GI bleed. Check the hemoglobin and do the rectal exam before the obvious blood appears.

• Consider PE in unexplained syncope. A large clot can present as a faint with subtle other clues.

• A classic vasovagal in a young patient needs little. Education and trigger avoidance, not an exhaustive cardiac workup.

• Orthostasis is a mechanism, not the end. Find why — dehydration, bleeding, or autonomic disease all present this way.

• Common mistake: discharging "vasovagal" syncope that was actually exertional or arrhythmic — the high-risk features were on the ECG and in the history.

Symptom-Based DDx & Plans — Gastrointestinal

108. Abdominal Pain

/AbdominalPain · differentiate by location + character, identify the surgical abdomen early · cholecystitis · pancreatitis · SBO · diverticulitis · appendicitis · colitis · Super Compact

Approach — localize the pain, then decide "surgical or not." Abdominal pain is differentiated by location + character + associated features, and the overriding early question is whether this is a surgical/emergent abdomen (peritonitis, perforation, ischemia, obstruction) needing urgent surgery, versus a medically managed process. Exam (peritoneal signs) + labs + CT abdomen/pelvis sort most of it; peritonitis, hemodynamic instability, or free air earn an immediate surgical call.

Key discriminators (by location): RUQ + Murphy's + fever → cholecystitis · epigastric radiating to back + high lipase → pancreatitis · diffuse/crampy + distension + vomiting + no flatus/stool → SBO · LLQ + fever → diverticulitis · periumbilical → RLQ migration → appendicitis · diffuse + bloody diarrhea/tenesmus → colitis · (and the can't-miss: out-of-proportion pain → mesenteric ischemia; tearing/pulsatile → AAA; epigastric + free air → perforation)

Initial Sx/Data (all comers): vitals, focused abdominal exam (peritoneal signs, localization), pregnancy test (reproductive age); CBC, BMP, LFTs, lipase, lactate (ischemia), UA; CT abdomen/pelvis (most causes), RUQ ultrasound (biliary); ECG/troponin (inferior MI mimic); upright CXR (free air); type + cross if surgical/bleeding · (pain out of proportion to a benign exam is mesenteric ischemia until excluded; and in older adults a "benign" abdomen can hide catastrophe — keep the threshold for imaging low)

Neg (don't-miss): denies missed surgical abdomen / perforation / peritonitis (rigid abdomen, free air → emergent surgery) · denies missed mesenteric ischemia (pain out of proportion, lactate, AF/vascular risk) · denies missed ruptured AAA / ectopic pregnancy · denies missed inferior MI / DKA presenting as abdominal pain · denies missed strangulated/closed-loop obstruction

DDx: cholecystitis · pancreatitis · small bowel obstruction · diverticulitis · appendicitis · colitis · (also: perforation, mesenteric ischemia, AAA, ectopic, nephrolithiasis, PUD, inferior MI, DKA)

Plan — by Diagnosis

CONSULT (as relevant): Surgery (surgical abdomen — appendicitis, perforation, ischemia, complicated obstruction) · GI (pancreatitis, colitis, scope) · IR (drainage, bleeding) · ICU (instability, ischemia, severe pancreatitis)

Cholecystitis

– Confirm: RUQ pain + Murphy's + fever, RUQ ultrasound (wall thickening, stones, pericholecystic fluid); HIDA if equivocal
– Plan: NPO, IV fluids, analgesia, antibiotics (gram-negative + anaerobe coverage); surgery consult for cholecystectomy (early preferred); cholecystostomy if poor surgical candidate
– Early cholecystectomy is preferred; watch for ascending cholangitis (Charcot triad → emergent biliary decompression/ERCP).

Pancreatitis

– Confirm: epigastric pain to back, lipase ≥3× ULN; identify cause (gallstones, alcohol, triglycerides); CT if severe/unclear
– Plan: aggressive IV fluid resuscitation (goal-directed), analgesia, NPO then early enteral nutrition as tolerated; treat the cause (ERCP for gallstone pancreatitis with cholangitis/obstruction); monitor for severity/organ failure
– Fluids and analgesia are the mainstay; severity (organ failure, necrosis) drives ICU disposition. Don't routinely give antibiotics in non-infected pancreatitis.

Small bowel obstruction

– Confirm: crampy pain, distension, vomiting, no flatus/stool, CT (transition point, dilated loops); prior surgery/adhesions/hernia
– Plan: NPO, NG tube decompression, IV fluids + electrolyte correction; surgery consult; conservative trial for adhesive partial SBO; surgery for complete/closed-loop/strangulation/ischemia or failure to resolve
– Closed-loop or strangulating obstruction (fever, leukocytosis, focal pain, lactate) is a surgical emergency — don't wait it out.

Diverticulitis

– Confirm: LLQ pain + fever, CT (diverticula, fat stranding, abscess/perforation)
– Plan: antibiotics (gram-negative + anaerobe) for complicated/systemic; bowel rest; abscess → IR drainage; perforation/peritonitis → surgery; outpatient management for select uncomplicated cases
– Stratify complicated (abscess, perforation, obstruction) vs uncomplicated — the former needs drainage or surgery.

Appendicitis

– Confirm: periumbilical → RLQ migration, anorexia, CT (or US/MRI in pregnancy); leukocytosis
– Plan: surgery consult for appendectomy; NPO, IV fluids, analgesia, antibiotics; (antibiotic-only management in selected uncomplicated cases per surgery)
– Appendectomy is definitive; perforation risk rises with delay — don't sit on a classic presentation.

Colitis

– Confirm: diffuse pain + diarrhea (± blood/tenesmus); stool studies (C. diff, cultures), CT (colitis pattern); distinguish infectious vs ischemic vs IBD
– Plan: treat by type — infectious (C. diff → oral vancomycin/fidaxomicin); ischemic colitis → supportive/bowel rest, surgery if necrosis; IBD flare → per GI; fluids/electrolytes; watch for toxic megacolon
– Toxic megacolon (distension, systemic toxicity, dilated colon) is a surgical emergency — avoid antimotility agents.

Cross-cutting

– Resuscitate + analgesia + antiemetics; NPO if surgical/obstruction; serial exams
– Trend: exam (peritoneal signs), vitals, WBC/lactate, imaging, response to therapy
– Escalation triggers: peritonitis/perforation/free air → emergent surgery; mesenteric ischemia → emergent surgery/vascular + ICU; ruptured AAA → emergent vascular surgery; cholangitis → urgent ERCP; toxic megacolon → surgery; instability → ICU
– Discharge checklist: surgical causes excluded/addressed + cause treated + tolerating diet; cause-specific follow-up (surgery/GI); antibiotic plan if applicable; return precautions (worsening/localizing pain, fever, vomiting, inability to tolerate PO, bleeding)

108. Abdominal Pain

/AbdominalPain · complete reference · localize, decide surgical-or-not early, image with CT, treat the cause · Full Card

Approach — Localize, Then Decide "Surgical or Not"

• Abdominal pain is differentiated by location, character, and associated features, and the overriding early question is whether this is a surgical or emergent abdomen (peritonitis, perforation, ischemia, obstruction) needing urgent surgery, versus a medically managed process.

• The exam (peritoneal signs), labs, and a CT abdomen and pelvis sort most of it; peritonitis, hemodynamic instability, or free air earn an immediate surgical call.

• Key discriminators by location: RUQ pain with a positive Murphy's sign and fever → cholecystitis; epigastric pain radiating to the back with a high lipase → pancreatitis; diffuse crampy pain with distension, vomiting, and no flatus or stool → SBO; LLQ pain with fever → diverticulitis; periumbilical pain migrating to the RLQ → appendicitis; diffuse pain with bloody diarrhea or tenesmus → colitis; and the can't-miss patterns — pain out of proportion → mesenteric ischemia, tearing or pulsatile → AAA, epigastric pain with free air → perforation.

Initial Symptoms / Data (all comers)

• Vitals, a focused abdominal exam (peritoneal signs, localization), and a pregnancy test (reproductive age).

• CBC, BMP, LFTs, lipase, lactate (ischemia), and UA; a CT abdomen and pelvis (most causes), an RUQ ultrasound (biliary disease), ECG and troponin (inferior MI mimic), and an upright CXR (free air); type and cross if surgical or bleeding.

• Pain out of proportion to a benign exam is mesenteric ischemia until excluded; and in older adults a "benign" abdomen can hide catastrophe — keep the threshold for imaging low.

Neg (don't-miss)

• Pt denies a missed surgical abdomen, perforation, or peritonitis (a rigid abdomen, free air → emergent surgery) and a missed mesenteric ischemia (pain out of proportion, lactate, AF or vascular risk).

• Pt denies a missed ruptured AAA or ectopic pregnancy and a missed inferior MI or DKA presenting as abdominal pain.

• Pt denies a missed strangulated or closed-loop obstruction.

DDx

Cholecystitis · pancreatitis · small bowel obstruction · diverticulitis · appendicitis · colitis · (also: perforation, mesenteric ischemia, AAA, ectopic pregnancy, nephrolithiasis, PUD, inferior MI, DKA)

Plan — by Diagnosis

CONSULT (as relevant): Surgery (surgical abdomen — appendicitis, perforation, ischemia, complicated obstruction) · GI (pancreatitis, colitis, endoscopy) · IR (drainage, bleeding) · ICU (instability, ischemia, severe pancreatitis)

• Cholecystitis — confirm: RUQ pain with a positive Murphy's sign and fever, an RUQ ultrasound (wall thickening, stones, pericholecystic fluid); HIDA if equivocal. Plan: NPO, IV fluids, analgesia, and antibiotics (gram-negative and anaerobe coverage); a surgery consult for cholecystectomy (early preferred); a cholecystostomy if a poor surgical candidate.

• Pancreatitis — confirm: epigastric pain to the back with a lipase at least 3 times the upper limit of normal; identify the cause (gallstones, alcohol, triglycerides); CT if severe or unclear. Plan: aggressive goal-directed IV fluid resuscitation, analgesia, and NPO then early enteral nutrition as tolerated; treat the cause (ERCP for gallstone pancreatitis with cholangitis or obstruction); monitor for severity and organ failure.

• Small bowel obstruction — confirm: crampy pain, distension, vomiting, and no flatus or stool, with a CT (transition point, dilated loops) and a history of prior surgery, adhesions, or hernia. Plan: NPO, NG tube decompression, IV fluids, and electrolyte correction; a surgery consult; a conservative trial for adhesive partial SBO; surgery for complete, closed-loop, or strangulating obstruction, ischemia, or failure to resolve.

• Diverticulitis — confirm: LLQ pain with fever and a CT (diverticula, fat stranding, abscess or perforation). Plan: antibiotics (gram-negative and anaerobe) for complicated or systemic disease; bowel rest; an abscess → IR drainage; perforation or peritonitis → surgery; outpatient management for select uncomplicated cases.

• Appendicitis — confirm: periumbilical pain migrating to the RLQ with anorexia, a CT (or ultrasound or MRI in pregnancy), and leukocytosis. Plan: a surgery consult for appendectomy; NPO, IV fluids, analgesia, and antibiotics; antibiotic-only management in selected uncomplicated cases per surgery.

• Colitis — confirm: diffuse pain with diarrhea (with or without blood or tenesmus); stool studies (C. difficile, cultures), a CT (colitis pattern); distinguish infectious versus ischemic versus IBD. Plan: treat by type — infectious (C. difficile → oral vancomycin or fidaxomicin); ischemic colitis → supportive care and bowel rest, surgery if necrosis; an IBD flare → per GI; fluids and electrolytes; watch for toxic megacolon.

• Cross-cutting: resuscitate, give analgesia and antiemetics, NPO if surgical or obstruction, and perform serial exams.

• Trend: the exam (peritoneal signs), vitals, WBC and lactate, imaging, and the response to therapy.

• Escalation triggers: peritonitis, perforation, or free air → emergent surgery; mesenteric ischemia → emergent surgery or vascular service and ICU; a ruptured AAA → emergent vascular surgery; cholangitis → urgent ERCP; toxic megacolon → surgery; instability → ICU.

• Discharge checklist: surgical causes excluded or addressed, the cause treated, and tolerating diet; cause-specific follow-up (surgery or GI); an antibiotic plan if applicable; return precautions for worsening or localizing pain, fever, vomiting, inability to tolerate PO, or bleeding.

Red Flags

• A rigid abdomen, peritoneal signs, or free air on imaging → perforation or peritonitis; emergent surgery.

• Pain out of proportion to the exam with a rising lactate → mesenteric ischemia; emergent surgery or vascular evaluation.

• Fever, leukocytosis, and focal pain in an obstruction → closed-loop or strangulating obstruction; don't wait it out.

• RUQ pain with fever, jaundice, and hypotension → ascending cholangitis; urgent ERCP.

• A pulsatile mass with tearing pain and hypotension → ruptured AAA; emergent vascular surgery.

Senior IM Resident Pearls

• The first question is surgical-or-not. Peritonitis, perforation, ischemia, and obstruction set the urgency before the precise diagnosis.

• Pain out of proportion is mesenteric ischemia. A soft abdomen with severe pain and a rising lactate, especially with AF, is the classic trap.

• Fluids and analgesia drive pancreatitis. Severity, not amylase, decides disposition — and don't reflexively give antibiotics without infection.

• Don't antimotility a colitis. In C. difficile or toxic megacolon, antimotility agents can precipitate disaster.

• The elderly abdomen lies. A catastrophe can present with an unimpressive exam — keep the imaging threshold low.

• Cholangitis needs decompression. Charcot's triad with instability is an ERCP emergency, not just antibiotics.

• Common mistake: giving analgesia and admitting "abdominal pain" without the CT or surgical evaluation that would catch the perforation, ischemia, or closed-loop obstruction.

Symptom-Based DDx & Plans — Gastrointestinal / Metabolic

109. Nausea / Vomiting

/NauseaVomiting · differentiate the dangerous (obstruction, DKA, intracranial) from the benign, then treat the cause + support · gastroenteritis · SBO · pancreatitis · DKA · medication effect · Super Compact

Approach — screen for the dangerous causes, then treat the cause and the consequences. Nausea/vomiting has a huge differential, so the job is to flag the can't-miss causes (bowel obstruction, DKA/metabolic, intracranial process, MI, pregnancy, ingestion) while managing the universal consequences — dehydration and electrolyte derangement. Pattern + associated features + a focused workup (glucose, electrolytes, lipase, imaging if obstruction) point to the cause.

Key discriminators: diffuse, diarrhea, sick contacts, self-limited → gastroenteritis · crampy pain + distension + no flatus/stool + bilious → SBO · epigastric to back + high lipase → pancreatitis · polyuria/polydipsia + high glucose + ketones + acidosis → DKA · temporal link to a new/culprit drug (opioids, chemo, etc.) → medication effect · (red flags: headache/neuro signs → intracranial; chest pain → MI; pregnancy; projectile/feculent → obstruction)

Initial Sx/Data (all comers): vitals + volume status, abdominal + focused neuro exam, pregnancy test (reproductive age); BMP (electrolytes, anion gap, glucose, renal), glucose + ketones if diabetic, lipase, CBC; imaging (CT/X-ray) if obstruction suspected; consider ECG/troponin, head imaging if neuro signs, medication review · (don't reflexively treat as gastroenteritis — vomiting without diarrhea, especially with abdominal distension, headache, or hyperglycemia, points to a more serious cause)

Neg (don't-miss): denies missed bowel obstruction (distension, no flatus/stool, bilious/feculent → imaging) · denies missed DKA/metabolic (glucose + gap + ketones) · denies missed intracranial process (headache, neuro signs, vomiting without nausea) · denies missed MI / pregnancy / ingestion · denies missing severe dehydration/electrolyte derangement (hypokalemia, metabolic alkalosis)

DDx: gastroenteritis · small bowel obstruction · pancreatitis · DKA · medication effect · (also: intracranial process/raised ICP, MI, pregnancy, gastroparesis, hepatobiliary, vestibular, ingestion/toxin, uremia)

Plan — by Diagnosis

CONSULT (as relevant): Surgery (obstruction) · GI (pancreatitis, refractory, gastroparesis) · Endocrine (DKA if complex) · Neurology (intracranial)

Gastroenteritis

– Confirm: diffuse, diarrhea, sick contacts, self-limited, benign exam
– Plan: supportive — rehydration (oral or IV), antiemetics (ondansetron), electrolyte correction; usually self-limited; stool studies only if severe/bloody/prolonged/immunocompromised; avoid unnecessary antibiotics
– Mostly supportive; the diagnosis is clinical and a diagnosis of exclusion once dangerous causes are off the table.

Small bowel obstruction

– Confirm: crampy pain, distension, no flatus/stool, bilious/feculent emesis, CT/X-ray
– Plan: NPO, NG decompression, IV fluids + electrolytes, surgery consult; conservative trial for adhesive partial; surgery for complete/strangulation/ischemia; see the abdominal pain card
– Vomiting + distension + no flatus is obstruction until imaged — not gastroenteritis.

Pancreatitis

– Confirm: epigastric to back, lipase ≥3× ULN; identify cause
– Plan: IV fluid resuscitation, analgesia, antiemetics, NPO then early enteral as tolerated; treat the cause; monitor severity; see the abdominal pain card
– Persistent vomiting with epigastric pain → check a lipase before calling it a stomach bug.

DKA

– Confirm: high glucose, anion-gap metabolic acidosis, ketones; identify trigger (infection, missed insulin)
– Plan: IV fluids first, then potassium repletion BEFORE/with insulin (don't start insulin if K low until repleted), IV insulin infusion, monitor glucose/gap/K closely, treat the trigger; see the hyperglycemia card
– Vomiting can be the presenting symptom of DKA — always check glucose and a gap. Fluids and potassium come before insulin gets aggressive.

Medication effect

– Confirm: temporal link to a culprit (opioids, chemo, antibiotics, others)
– Plan: adjust/stop the offending agent where possible; targeted antiemetic prophylaxis (e.g. for chemo-induced); supportive care
– Opioid- and chemo-induced nausea is predictable — prophylax and adjust rather than just rescue.

Cross-cutting

– Manage the consequences (all comers): rehydrate, correct electrolytes (hypokalemia + metabolic alkalosis common with vomiting), antiemetics, monitor renal function
– Trend: volume status, electrolytes, symptom control, the corrected cause
– Escalation triggers: obstruction with strangulation → surgery; DKA → close monitoring ± ICU; intracranial process → neuro/imaging; intractable vomiting with severe derangement → admit + IV management; MI → cardiology
– Discharge checklist: dangerous causes excluded + cause treated + tolerating PO + electrolytes corrected; antiemetic plan; cause-specific follow-up; return precautions (inability to keep fluids down, abdominal distension, severe pain, confusion, decreased urine)

109. Nausea / Vomiting

/NauseaVomiting · complete reference · flag obstruction, DKA, and intracranial causes, then treat the cause and the dehydration and electrolyte consequences · Full Card

Approach — Screen the Dangerous, Then Treat Cause and Consequences

• Nausea and vomiting has a huge differential, so the job is to flag the can't-miss causes (bowel obstruction, DKA or metabolic derangement, an intracranial process, MI, pregnancy, ingestion) while managing the universal consequences — dehydration and electrolyte derangement.

• The pattern, associated features, and a focused workup (glucose, electrolytes, lipase, imaging if obstruction) point to the cause.

• Key discriminators: diffuse symptoms with diarrhea, sick contacts, and a self-limited course → gastroenteritis; crampy pain with distension, no flatus or stool, and bilious emesis → SBO; epigastric pain to the back with a high lipase → pancreatitis; polyuria, polydipsia, a high glucose, ketones, and acidosis → DKA; a temporal link to a new or culprit drug (opioids, chemotherapy) → medication effect; and red flags — headache or neuro signs → intracranial process, chest pain → MI, pregnancy, projectile or feculent emesis → obstruction.

Initial Symptoms / Data (all comers)

• Vitals with volume status, an abdominal and focused neuro exam, and a pregnancy test (reproductive age).

• BMP (electrolytes, anion gap, glucose, renal function), glucose and ketones if diabetic, lipase, and CBC; imaging (CT or X-ray) if obstruction is suspected; consider ECG and troponin, head imaging if there are neuro signs, and a medication review.

• Don't reflexively treat it as gastroenteritis — vomiting without diarrhea, especially with abdominal distension, headache, or hyperglycemia, points to a more serious cause.

Neg (don't-miss)

• Pt denies a missed bowel obstruction (distension, no flatus or stool, bilious or feculent emesis → imaging) and a missed DKA or metabolic derangement (glucose, gap, ketones).

• Pt denies a missed intracranial process (headache, neuro signs, vomiting without nausea) and a missed MI, pregnancy, or ingestion.

• Pt denies missing severe dehydration or electrolyte derangement (hypokalemia, metabolic alkalosis).

DDx

Gastroenteritis · small bowel obstruction · pancreatitis · DKA · medication effect · (also: an intracranial process or raised ICP, MI, pregnancy, gastroparesis, hepatobiliary disease, vestibular causes, ingestion or toxin, uremia)

Plan — by Diagnosis

CONSULT (as relevant): Surgery (obstruction) · GI (pancreatitis, refractory symptoms, gastroparesis) · Endocrine (DKA if complex) · Neurology (intracranial process)

• Gastroenteritis — confirm: diffuse symptoms, diarrhea, sick contacts, a self-limited course, and a benign exam. Plan: supportive — rehydration (oral or IV), antiemetics (ondansetron), and electrolyte correction; usually self-limited; stool studies only if severe, bloody, prolonged, or immunocompromised; avoid unnecessary antibiotics.

• Small bowel obstruction — confirm: crampy pain, distension, no flatus or stool, and bilious or feculent emesis, with a CT or X-ray. Plan: NPO, NG decompression, IV fluids and electrolytes, and a surgery consult; a conservative trial for adhesive partial obstruction; surgery for complete, strangulating, or ischemic obstruction (see the abdominal pain card).

• Pancreatitis — confirm: epigastric pain to the back with a lipase at least 3 times the upper limit of normal; identify the cause. Plan: IV fluid resuscitation, analgesia, antiemetics, and NPO then early enteral nutrition as tolerated; treat the cause; monitor severity (see the abdominal pain card).

• DKA — confirm: a high glucose with an anion-gap metabolic acidosis and ketones; identify the trigger (infection, missed insulin). Plan: IV fluids first, then potassium repletion before or with insulin (don't start insulin if the potassium is low until it's repleted), an IV insulin infusion, monitor glucose, gap, and potassium closely, and treat the trigger (see the hyperglycemia card).

• Medication effect — confirm: a temporal link to a culprit (opioids, chemotherapy, antibiotics, others). Plan: adjust or stop the offending agent where possible; targeted antiemetic prophylaxis (e.g. for chemotherapy-induced nausea); supportive care.

• Cross-cutting — manage the consequences (all comers): rehydrate, correct electrolytes (hypokalemia and metabolic alkalosis are common with vomiting), give antiemetics, and monitor renal function.

• Trend: volume status, electrolytes, symptom control, and the corrected cause.

• Escalation triggers: obstruction with strangulation → surgery; DKA → close monitoring with possible ICU; an intracranial process → neurology and imaging; intractable vomiting with severe derangement → admit and IV management; MI → cardiology.

• Discharge checklist: dangerous causes excluded, the cause treated, tolerating PO, and electrolytes corrected; an antiemetic plan; cause-specific follow-up; return precautions for inability to keep fluids down, abdominal distension, severe pain, confusion, or decreased urine.

Red Flags

• Vomiting with distension and no flatus or stool → bowel obstruction; image, don't treat as a stomach bug.

• Vomiting with a high glucose and acidosis → DKA; check the gap and ketones.

• Vomiting (especially without nausea) with headache or neuro signs → a raised-ICP intracranial process.

• Vomiting with chest pain → consider an MI, particularly inferior.

• Severe hypokalemia and metabolic alkalosis from protracted vomiting → correct before complications.

Senior IM Resident Pearls

• Don't default to gastroenteritis. Vomiting without diarrhea, with distension, headache, or hyperglycemia, is a different and more dangerous problem.

• Check a glucose and a gap. DKA can present primarily as vomiting before the classic picture is obvious.

• Vomiting without nausea is a red flag. It suggests a central, raised-ICP cause.

• Protracted vomiting deranges potassium. Hypokalemia and metabolic alkalosis are predictable and worth correcting.

• Prophylax predictable nausea. Opioid- and chemotherapy-induced nausea responds better to prevention than rescue.

• Fluids and potassium precede aggressive insulin in DKA. Don't drop the potassium further by leading with insulin.

• Common mistake: labeling isolated vomiting "gastroenteritis" and missing the obstruction, DKA, or intracranial process hiding behind it.

Symptom-Based DDx & Plans — Gastrointestinal

110. GI Bleeding

/GIBleeding · resuscitate first, then localize upper vs lower and treat the source · PUD · gastritis · diverticular bleed · AVM/angiodysplasia · colon cancer · Super Compact

Approach — resuscitate first, then localize (upper vs lower), then treat the source. The opening move in any GI bleed is hemodynamic: two large-bore IVs, type & cross, fluids, and transfusion (restrictive ~7 g/dL, higher with active bleeding/cardiac disease), plus reversing/holding anticoagulation. Only then differentiate: upper (hematemesis/melena → EGD) vs lower (hematochezia → colonoscopy), risk-stratify, and direct endoscopy/IR/surgery to the source. Cover variceal possibilities early in any cirrhotic.

Key discriminators: epigastric pain/NSAID or H. pylori use/melena/hematemesis → PUD (upper) · diffuse oozing, NSAID/alcohol/stress → gastritis (upper) · painless brisk hematochezia in an older adult, self-limited → diverticular bleed (lower) · painless recurrent obscure bleeding, often older/CKD/aortic stenosis → AVM/angiodysplasia · iron-deficiency anemia, weight loss, change in bowel habits, occult/overt bleeding → colon cancer · (cirrhosis + hematemesis → variceal — treat empirically)

Initial Sx/Data (all comers): vitals + orthostatics + perfusion, rectal exam (melena vs hematochezia); CBC (Hgb — may lag acutely), BMP (BUN:Cr ratio elevated in upper bleed), LFTs/coags/INR, type & cross, lactate; risk score (Glasgow-Blatchford); EGD for upper, colonoscopy for lower; CT angiography/tagged RBC scan for brisk obscure bleeding · (an initial normal hemoglobin does not exclude a significant acute bleed — it lags; resuscitate by hemodynamics and clinical picture, not the first Hgb)

Neg (don't-miss): denies under-resuscitated hemorrhagic shock (resuscitate before/with the workup) · denies missed variceal bleed in a cirrhotic (needs octreotide + antibiotics + urgent EGD) · denies missed brisk/ongoing bleed needing urgent intervention · denies missed colon cancer as the source (don't stop at "diverticular/hemorrhoidal" without completing the colon workup) · denies failing to reverse a coagulopathy

DDx: peptic ulcer disease · gastritis · diverticular bleed · AVM/angiodysplasia · colon cancer · (also: esophageal/gastric varices, Mallory-Weiss tear, hemorrhoids/anorectal, malignancy — upper, ischemic colitis, aortoenteric fistula)

Plan — by Diagnosis

CONSULT (as relevant): GI (endoscopy — first-line) · IR (embolization for refractory/brisk bleeding) · Surgery (uncontrolled bleeding, malignancy) · ICU (massive bleed, instability)

Peptic ulcer disease

– Confirm: epigastric pain, NSAID/H. pylori, melena/hematemesis, EGD (ulcer with stigmata)
– Plan: IV PPI (e.g. pantoprazole 80 mg bolus then 8 mg/hr infusion, or high-dose intermittent), urgent EGD with endoscopic hemostasis (clip/thermal/injection); test + treat H. pylori; stop NSAIDs; transfuse per threshold
– PPI infusion + endoscopic hemostasis is the core; always test and treat H. pylori and stop the offending NSAID.

Gastritis

– Confirm: diffuse mucosal oozing, NSAID/alcohol/stress, EGD
– Plan: IV PPI, remove the insult (NSAIDs, alcohol), supportive care + transfusion as needed; stress-ulcer prophylaxis in at-risk inpatients
– Usually less brisk than ulcer bleeds; the work is removing the insult and acid suppression.

Diverticular bleed

– Confirm: painless brisk hematochezia, older adult, colonoscopy (or CTA if brisk)
– Plan: resuscitate; usually self-limited — colonoscopy for diagnosis ± endoscopic hemostasis; CTA/tagged RBC scan + IR embolization if brisk/ongoing; surgery if uncontrolled/recurrent
– Most diverticular bleeds stop on their own — but the brisk ones need CTA/IR localization fast.

AVM / angiodysplasia

– Confirm: painless recurrent/obscure bleeding, often older/CKD/aortic stenosis, endoscopy (may need push/capsule for small bowel)
– Plan: endoscopic hemostasis (argon plasma coagulation/cautery); IR embolization if refractory; treat anemia; address contributing factors (anticoagulation, valve disease)
– Suspect angiodysplasia in recurrent obscure bleeds, especially with CKD or aortic stenosis (Heyde syndrome).

Colon cancer

– Confirm: iron-deficiency anemia, weight loss, change in bowel habits, occult/overt bleeding, colonoscopy + biopsy
– Plan: colonoscopy with biopsy for diagnosis/staging; surgical/oncology referral; manage acute bleeding; complete the colon evaluation — don't attribute lower bleeding to hemorrhoids/diverticula without it
– Iron-deficiency anemia or a change in bowel habits in an older adult mandates the full colon workup — don't stop at the easy explanation.

Cross-cutting

– Resuscitation bundle (all comers): two large-bore IVs, type & cross, crystalloid; transfuse RBCs (restrictive ~7, higher if active bleeding/cardiac); correct coagulopathy/platelets, reverse/hold anticoagulants; restrictive transfusion improves outcomes in non-exsanguinating bleeds
– Cirrhotic/suspected variceal: octreotide infusion + prophylactic antibiotics (e.g. ceftriaxone) + urgent EGD for banding
– Trend: hemodynamics/orthostatics, serial Hgb, transfusion requirement, rebleeding signs
– Escalation triggers: hemodynamic instability/massive bleed → ICU + massive transfusion protocol; refractory bleeding → IR embolization/surgery; variceal → urgent EGD ± balloon tamponade/TIPS
– Discharge checklist: bleeding source identified + controlled + hemodynamically stable + stable Hgb; H. pylori/NSAID addressed (PUD); anticoagulation reassessed; colon workup completed where indicated; GI follow-up; return precautions (recurrent bleeding — hematemesis/melena/hematochezia, lightheadedness, weakness)

110. GI Bleeding

/GIBleeding · complete reference · resuscitate first, localize upper vs lower, treat the source, never miss varices or cancer · Full Card

Approach — Resuscitate First, Then Localize, Then Treat the Source

• The opening move in any GI bleed is hemodynamic: two large-bore IVs, type and cross, fluids, and transfusion (a restrictive threshold around 7 g/dL, higher with active bleeding or cardiac disease), plus reversing or holding anticoagulation.

• Only then differentiate: upper (hematemesis or melena → EGD) versus lower (hematochezia → colonoscopy), risk-stratify, and direct endoscopy, IR, or surgery to the source.

• Cover variceal possibilities early in any cirrhotic patient.

• Key discriminators: epigastric pain with NSAID or H. pylori use and melena or hematemesis → PUD (upper); diffuse oozing with NSAID, alcohol, or stress → gastritis (upper); painless brisk hematochezia in an older adult, often self-limited → diverticular bleed (lower); painless recurrent obscure bleeding, often with CKD or aortic stenosis → AVM or angiodysplasia; iron-deficiency anemia, weight loss, or a change in bowel habits → colon cancer; cirrhosis with hematemesis → variceal (treat empirically).

Initial Symptoms / Data (all comers)

• Vitals with orthostatics and perfusion, and a rectal exam (melena versus hematochezia).

• CBC (hemoglobin — may lag acutely), BMP (an elevated BUN-to-creatinine ratio in an upper bleed), LFTs, coagulation studies, and INR, type and cross, and lactate; a risk score (Glasgow-Blatchford); EGD for an upper source, colonoscopy for a lower source; CT angiography or a tagged RBC scan for brisk obscure bleeding.

• An initial normal hemoglobin does not exclude a significant acute bleed — it lags; resuscitate by hemodynamics and the clinical picture, not the first hemoglobin.

Neg (don't-miss)

• Pt denies under-resuscitated hemorrhagic shock (resuscitate before or with the workup) and a missed variceal bleed in a cirrhotic (needs octreotide, antibiotics, and an urgent EGD).

• Pt denies a missed brisk or ongoing bleed needing urgent intervention and a missed colon cancer as the source (don't stop at "diverticular" or "hemorrhoidal" without completing the colon workup).

• Pt denies failing to reverse a coagulopathy.

DDx

Peptic ulcer disease · gastritis · diverticular bleed · AVM or angiodysplasia · colon cancer · (also: esophageal or gastric varices, a Mallory-Weiss tear, hemorrhoids or anorectal sources, upper malignancy, ischemic colitis, an aortoenteric fistula)

Plan — by Diagnosis

CONSULT (as relevant): GI (endoscopy — first-line) · IR (embolization for refractory or brisk bleeding) · Surgery (uncontrolled bleeding, malignancy) · ICU (massive bleed, instability)

• Peptic ulcer disease — confirm: epigastric pain, NSAID or H. pylori use, and melena or hematemesis, with an EGD (an ulcer with stigmata). Plan: an IV PPI (e.g. pantoprazole 80 mg bolus then an 8 mg/hr infusion, or high-dose intermittent dosing), an urgent EGD with endoscopic hemostasis (clip, thermal, or injection); test and treat H. pylori; stop NSAIDs; transfuse per threshold.

• Gastritis — confirm: diffuse mucosal oozing with NSAID, alcohol, or stress, on EGD. Plan: an IV PPI, remove the insult (NSAIDs, alcohol), supportive care and transfusion as needed; stress-ulcer prophylaxis in at-risk inpatients.

• Diverticular bleed — confirm: painless brisk hematochezia in an older adult, with colonoscopy (or CTA if brisk). Plan: resuscitate; usually self-limited — colonoscopy for diagnosis with possible endoscopic hemostasis; a CTA or tagged RBC scan and IR embolization if brisk or ongoing; surgery if uncontrolled or recurrent.

• AVM / angiodysplasia — confirm: painless recurrent or obscure bleeding, often with CKD or aortic stenosis, on endoscopy (may need push enteroscopy or capsule for the small bowel). Plan: endoscopic hemostasis (argon plasma coagulation or cautery); IR embolization if refractory; treat the anemia; address contributing factors (anticoagulation, valve disease).

• Colon cancer — confirm: iron-deficiency anemia, weight loss, or a change in bowel habits with occult or overt bleeding, on colonoscopy with biopsy. Plan: colonoscopy with biopsy for diagnosis and staging; surgical and oncology referral; manage acute bleeding; complete the colon evaluation — don't attribute lower bleeding to hemorrhoids or diverticula without it.

• Cross-cutting — resuscitation bundle (all comers): two large-bore IVs, type and cross, and crystalloid; transfuse RBCs (a restrictive threshold around 7, higher if there is active bleeding or cardiac disease); correct coagulopathy and platelets, and reverse or hold anticoagulants; restrictive transfusion improves outcomes in non-exsanguinating bleeds.

• Cirrhotic or suspected variceal: an octreotide infusion, prophylactic antibiotics (e.g. ceftriaxone), and an urgent EGD for banding.

• Trend: hemodynamics and orthostatics, serial hemoglobin, transfusion requirement, and signs of rebleeding.

• Escalation triggers: hemodynamic instability or a massive bleed → ICU and a massive transfusion protocol; refractory bleeding → IR embolization or surgery; a variceal bleed → an urgent EGD with possible balloon tamponade or TIPS.

• Discharge checklist: the bleeding source identified and controlled, hemodynamically stable, with a stable hemoglobin; H. pylori and NSAID use addressed (PUD); anticoagulation reassessed; the colon workup completed where indicated; GI follow-up; return precautions for recurrent bleeding (hematemesis, melena, hematochezia), lightheadedness, or weakness.

Red Flags

• Hemodynamic instability or a massive bleed → hemorrhagic shock; ICU and a massive transfusion protocol.

• Cirrhosis with hematemesis → a variceal bleed; octreotide, antibiotics, and an urgent EGD before you have the diagnosis.

• An initial normal hemoglobin → doesn't exclude a serious acute bleed; it lags, so resuscitate by hemodynamics.

• Brisk ongoing bleeding not localized by endoscopy → CTA or tagged RBC scan and IR embolization.

• Iron-deficiency anemia or a change in bowel habits → complete the colon workup; don't stop at diverticula or hemorrhoids.

Senior IM Resident Pearls

• Resuscitate before you diagnose. Two large-bore IVs, type and cross, and transfusion come before the endoscopy in an unstable bleed.

• The first hemoglobin lags. A normal value early doesn't reassure — the clinical picture and hemodynamics do.

• Treat the cirrhotic empirically for varices. Octreotide and antibiotics go in before the EGD confirms the source.

• Restrictive transfusion wins. Over-transfusing a non-exsanguinating bleed worsens outcomes, including variceal rebleeding.

• A high BUN-to-creatinine ratio points upper. Digested blood raises the BUN — a useful bedside clue.

• Don't stop at the easy lower source. Iron-deficiency anemia or a bowel-habit change demands the full colon evaluation for cancer.

• Common mistake: rushing to endoscopy on an under-resuscitated, uncorrected-coagulopathy patient — stabilize and reverse first, then scope.