Cerebrovascular Complications of COVID-19 on Venovenous Extracorporeal Membrane Oxygenation

Objectives: Evidence of cerebrovascular complications in COVID-19 requiring venovenous extracorporeal membrane oxygenation (ECMO) is limited. Our study aims to characterize the prevalence and risk factors of stroke secondary to COVID-19 in patients on venovenous ECMO. Design: We analyzed prospectively collected observational data, using univariable and multivariable survival modeling to identify risk factors for stroke. Cox proportional hazards and Fine-Gray models were used, with death and discharge treated as competing risks. Setting: Three hundred eighty institutions in 53 countries in the COVID-19 Critical Care Consortium (COVID Critical) registry. Patients: Adult COVID-19 patients who were supported by venovenous ECMO. Interventions: None. Measurements and main results: Five hundred ninety-five patients (median age [interquartile range], 51 yr [42-59 yr]; male: 70.8%) had venovenous ECMO support. Forty-three patients (7.2%) suffered strokes, 83.7% of which were hemorrhagic. In multivariable survival analysis, obesity (adjusted hazard ratio [aHR], 2.19; 95% CI, 1.05-4.59) and use of vasopressors before ECMO (aHR, 2.37; 95% CI, 1.08-5.22) were associated with an increased risk of stroke. Forty-eight-hour post-ECMO Paco2-pre-ECMO Paco2/pre-ECMO Paco2 (relative ΔPaco2) of negative 26% and 48-hour post-ECMO Pao2-pre-ECMO Pao2/pre-ECMO Pao2 (relative ΔPao2) of positive 24% at 48 hours of ECMO initiation were observed in stroke patients in comparison to relative ΔPaco2 of negative 17% and relative ΔPao2 of positive 7% in the nonstroke group. Patients with acute stroke had a 79% in-hospital mortality compared with 45% mortality for stroke-free patients. Conclusions: Our study highlights the association of obesity and pre-ECMO vasopressor use with the development of stroke in COVID-19 patients on venovenous ECMO. Also, the importance of relative decrease in Paco2 and moderate hyperoxia within 48 hours after ECMO initiation were additional risk factors.