CATASTROPHIC PULMONARY EMBOLISM SUCCESSFULLY TREATED WITH EXTRACORPOREAL MEMBRANE OXYGENATION

Abstract

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) is increasingly recognized as a modality for cardiopulmonary support in high-risk pulmonary embolism (PE). We report a successful application of VA ECMO to support a patient following cardiac arrest secondary to massive saddle PE. CASE PRESENTATION: A 35 year old woman was admitted with new cranial nerve palsies, concerning for neurosarcoidosis versus lymphoma. On hospital day (HD) 11 she became dyspneic and desaturated to 88% on room air; other vitals remained stable. CT chest revealed bilateral pulmonary artery occlusion with right heart strain. NT-proBNP was 3086 pg/mL (ref <125). Multidisciplinary Pulmonary Embolism Response Team (PERT) stratified her as "intermediate-high risk" PE, and recommended therapeutic heparin infusion, with resultant clinical improvement. On HD16 she developed acute chest pain with new tachycardia (HR 130), hypotension (BP 87/65) and increased oxygen requirements. S1Q3T3 pattern was noted on EKG. PE Severity Index (PESI) was 125 (Class IV), and PERT elected for urgent catheter-directed thrombectomy. Prior to procedure she suffered a cardiac arrest, and received ACLS plus systemic thrombolytics, with return of spontaneous circulation after 20 minutes. Post-arrest suction thrombectomy removed large clot burden, but with persistent hypotension despite inhaled nitric oxide, vasopressor and inotropic support and severe right ventricle (RV) systolic dysfunction on echocardiogram, she was peripherally cannulated for VA-ECMO. Her ECMO course was complicated by renal failure requiring renal replacement therapy and hemoperitoneum requiring blood transfusion. Vasopressors were weaned off on ECMO day 4, and she was decannulated on ECMO day 6. She was discharged on HD42, neurologically intact and with recovered cardiac and renal function. DISCUSSION: High-risk PE, defined by acute PE with hemodynamic instability, shock, or cardiac arrest, is associated with high mortality. VA ECMO allows for maintenance of organ perfusion and oxygenation by mechanically bypassing and decompressing the failing RV and pulmonary circulation, offering hemodynamic and respiratory support to allow for reperfusion strategies or spontaneous thrombolysis on heparin. ECMO is increasingly available, with mobile teams allowing for rapid deployment. The literature on ECMO as a rescue therapy for catastrophic PE is limited to small case series, and recent meta analyses were unable to draw definitive conclusions (1, 2). 2019 European guidelines suggest that mechanical cardiopulmonary support may be helpful for high-risk PE with circulatory collapse (3). CONCLUSIONS: This case adds to reports of successful use of VA-ECMO for high-risk PE. Early ECMO consultation and timely appropriate use may prevent sudden cardiac death. Further research is needed to determine what role ECMO may play as an early intervention rather than a salvage procedure. REFERENCE #1: Pozzi, Matteo, et al. "Efficacy and safety of extracorporeal membrane oxygenation for high-risk pulmonary embolism: A systematic review and meta-analysis." Vascular Medicine 25.5 (2020): 460-467. REFERENCE #2: Baldetti, Luca, et al. "Use of extracorporeal membrane oxygenation in high-risk acute pulmonary embolism." Artificial Organs (2020). REFERENCE #3: Konstantinides, Stavros V., et al. "2019 ESC Guidelines for the diagnosis and management of acute pulmonary embolism developed in collaboration with the European Respiratory Society (ERS) The Task Force for the diagnosis and management of acute pulmonary embolism of the European Society of Cardiology (ESC)." European heart journal 41.4 (2020): 543-603. DISCLOSURES: no disclosure on file for Stephanie Nonas; No relevant relationships by Jonathan Taylor, source=Web Response