(1258) Symptomatic Crashing of Acute Pulmonary Edema (SCAPE) Syndrome: An Emergency to Tackle

Introduction: Symptomatic Crashing of Acute Pulmonary Edema (SCAPE) is sudden onset of acute pulmonary edema accompanied by severe systolic hypertension. It can be challenging to differentiate between SCAPE and acute heart failure exacerbation. Prompt intervention is crucial to prevent the need for endotracheal intubation and urgent complications.

Description: An 82-year-old gentleman with a medical history of chronic obstructive pulmonary disease (COPD), end-stage renal disease (ESRD), heart failure with preserved ejection fraction, hypertension presented with sudden shortness of breath for about 12 hours. Despite maintaining regular hemodialysis and adhering to home medications, he arrived in acute respiratory distress. His came with difficulty speaking in full sentences, using accessory muscles, initial blood pressure was elevated at 215/91 mmHg, and his oxygen saturation on room air was 86%. Lung exam reveals minimal bilateral wheezes, disproportionate crackles given his clinical presentation, mild lower extremity swelling. Point of care ultrasound (PoCUS) showed diffuse B-line. Treatment involved initiating high-dose nitroglycerin at 200 mcg/mL and administering BiPAP. Additionally, he was also managed for an acute exacerbation of COPD with bronchodilators with systemic steroids. The patient’s condition improved on this regimen without need for an urgent hemodialysis, supporting SCAPE. He received his scheduled hemodialysis on the following day and was subsequently discharged home.

Discussion: SCAPE results from surge in sympathetic activity leading to release of catecholamines, increases arterial tone and fluid redistribution, causing sudden pulmonary edema even in euvolemic individuals. The renin-angiotensin-aldosterone system contributes to increased peripheral vascular resistance, sodium and water retention, exacerbating cardiac function and pulmonary venous return. SCAPE is triggered by volume overload, uncontrolled hypertension, stress, acute coronary or valvular abnormalities. Higher doses of nitroglycerin (>100 mcg/min) have shown to be beneficial in reducing arterial tone and afterload. Immediate initiation of BiPAP or CPAP is essential for managing pulmonary congestion and preventing intubation. Lowering blood pressure is another critical aspect of treatment.