SCAPE
Formal Definition
Sympathetic Crashing Acute Pulmonary Edema — a specific phenotype of acute decompensated heart failure characterized by sudden, severe flash pulmonary edema with profound hypertension and sympathetic surge, typically presenting to the ED with extreme dyspnea, hypoxemia, pink frothy sputum, hypertension (>180/100), and diaphoresis; pathophysiology involves acute afterload mismatch from severe hypertension in a heart with limited reserve, leading to rapid pulmonary venous pressure rise and alveolar flooding; treated as a hypertensive emergency with vasodilators and aggressive afterload reduction rather than traditional CHF diuresis-first approach.
How It's Used on the Ward
"SCAPE" — the patient is in extremis, hypertensive, drowning in their own pulmonary edema with a sympathetic surge driving tachycardia and agitation; the ED treatment is distinctly different from regular CHF exacerbation — start with afterload reduction (nitroglycerin) and BiPAP, diuresis comes second; mortality is high without prompt recognition.
Example
""68-year-old hypertensive man with preserved EF calling 911 for sudden severe dyspnea — felt fine eating dinner, dyspneic within 30 minutes, now pink frothy sputum, BP 220/118, HR 124, SpO2 78% on room air, bilateral rales. Diagnosis: SCAPE. Started BiPAP 100% FiO2, IV nitroglycerin started at 200 mcg/min (high-dose drip, rapid uptitration to 400), small IV fentanyl bolus for sympathetic suppression, only modest diuresis (40mg IV furosemide) until BP controlled. Within 30 minutes: BP 140/82, SpO2 94% on BiPAP, patient calmer. Admitted to CCU.""
Clinical Context
Treatment pillars (in order): (1) AFTERLOAD REDUCTION — IV nitroglycerin (start 200 mcg/min, double q3-5min up to 400+ until BP <160/100), or IV nitroprusside if severe. BiPAP (CPAP 10-15 cmH2O + PS 10-15 cmH2O) simultaneously: reduces preload, increases alveolar recruitment, decreases work of breathing. (2) Sympathetic suppression — small dose IV fentanyl (50-100 mcg) can blunt catecholamine surge; some clinicians add low-dose IV metoprolol. (3) Diuresis — comes second, modest dose only (furosemide 40mg IV); avoid aggressive diuresis first — patient is often preload-dependent and profoundly hypertensive, diuresis without BP control worsens afterload. (4) Avoid: intubation if possible (BiPAP works; intubation in SCAPE has high mortality), high-dose Morphine (hypotension risk, modern guidelines), traditional "CHF exacerbation" bundle without aggressive afterload reduction. SCAPE vs typical APE: SCAPE = hypertensive, sympathetic surge, flash onset, preserved EF common. Typical APE = gradual, hypotension normal/low, often non-compliant with meds/diet.