Episode 218: Sympathetic Crashing Acute Pulmonary Edema (SCAPE)

We discuss the diagnosis and management of SCAPE in the ED. Hosts: Naz Sarpoulaki, MD, MPH Brian Gilberti, MD https://media.blubrry.com/coreem/content.blubrry.com/coreem/SCAPEv2.mp3 Download Leave a Comment Tags: Acute Pulmonary Edema , Critical Care Show Notes Core EM Modular CME Course Maximize your commute with the new Core EM Modular CME Course, featuring the most essential content distilled from our top-rated podcast episodes. This course offers 12 audio-based modules packed with pearls! Information and link below. Course Highlights: Credit: 12.5 AMA PRA Category 1 Credits™ Curriculum: Comprehensive coverage of Core Emergency Medicine, with 12 modules spanning from Critical Care to Pediatrics. Cost: Free for NYU Learners $250 for Non-NYU Learners Click Here to Register and Begin Module 1 The Clinical Case Presentation: 60-year-old male with a history of HTN and asthma. EMS Findings: Severe respiratory distress, SpO₂ in the 60s on NRB, HR 120, BP 230/180. Exam: Diaphoretic, diffuse crackles, warm extremities, pitting edema, and significant fatigue/work of breathing. Pre-hospital meds: NRB, Duonebs, Dexamethasone, and IM Epinephrine (under the assumption of severe asthma/anaphylaxis). Differential Diagnosis for the Hypoxic/Tachypneic Patient Pulmonary: Asthma/COPD, Pneumonia, ARDS, PE, Pneumothorax, Pulmonary Edema, ILD, Anaphylaxis. Cardiac: CHF, ACS, Tamponade. Systemic: Anemia, Acidosis. Neuro: Neuromuscular weakness. What is SCAPE? Sympathetic Crashing Acute Pulmonary Edema (SCAPE) is characterized by a sudden, massive sympathetic surge leading to intense vasoconstriction and a precipitous rise in afterload. Pathophysiology: Unlike HFrEF, these patients are often euvolemic or even hypovolemic . The primary issue is fluid maldistribution (fluid shifting from the vasculature into the lungs) due to extreme afterload. Bedside Diagnosis: POCUS vs. CXR POCUS is the gold standard for rapid bedside diagnosis. Lung Ultrasound: Look for diffuse B-lines (≥3 in ≥2 bilateral zones). Cardiac: Assess LV function and check for pericardial effusion. Why not CXR? A meta-analysis shows LUS has a sensitivity of ~88% and specificity of ~90% , whereas CXR sensitivity is only ~73% . Importantly, up to 20% of patients with decompensated HF will have a normal CXR. Management Strategy 1. NIPPV (CPAP or BiPAP) Start NIPPV immediately to reduce preload/afterload and recruit alveoli. Settings: CPAP 5–8 cm H₂O or BiPAP 10/5 cm H₂O. Escalate EPAP quickly but keep pressures to avoid gastric insufflation. Evidence: NIPPV reduces mortality ( NNT 17) and intubation rates ( NNT 13). 2. High-Dose Nitroglycerin The goal is to drop SBP to within minutes. No IV Access: 3–5 SL tabs (0.4 mg each) simultaneously. IV Bolus: 500–1000 mcg over 2 minutes. IV Infusion: Start at 100–200 mcg/min; titrate up rapidly (doses > 800 mcg/min may be required). Safety: ACEP policy supports high-dose NTG as both safe and effective for hypertensive HF. Use a dedicated line/short tubing to prevent adsorption issues. 3. Refractory Hypertension If SBP remains > 160 mmHg despite NIPPV and aggressive NTG, add a second vasodilator: Clevidipine: Ultra-short-acting calcium channel blocker (titratable and rapid). Nicardipine: Effective alternative for rapid BP control. Enalaprilat: Consider if the above are unavailable. Troubleshooting & Pitfalls The “Mask Intolerant” Patient Hypoxia is the primary driver of agitation. NIPPV is the best sedative. * Pharmacology: If needed, use small doses of benzodiazepines (Midazolam 0.5–1 mg IV). AVOID Morphine: Data suggests higher rates of adverse events, invasive ventilation, and mortality. A 2022 RCT was halted early due to harm in the morphine arm (43% adverse events vs. 18% with midazolam). The Role of Diuretics In SCAPE, diuretics are not first-line. The problem is redistribution, not volume excess. Diuretics will not help in the first 15–30 minutes and may worsen kidney function in a (relatively) hypovolemic patient. Delay Diuretics until the p

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