The Effect of acute Limb Ischemia on Mortality in Patients Undergoing Femoral Veno-arterial Extracorporeal Membrane Oxygenation

Abstract Introduction Extracorporeal membrane oxygenation (ECMO) is a life saving modality increasingly used in the management cardiopulmonary failure. However, ECMO itself is not without major complications. Mortality remains high, and morbidity such as stroke, renal failure, and acute threatening limb ischemia (ALI) are common among surviving patients. We analyzed the effect of one of these complications, ALI, on the survival of patients receiving veno-arterial ECMO (VA ECMO) with femoral cannulation. Methods Patients with cardiopulmonary failure supported by VA ECMO inserted through femoral cannulation at two institutions from December 2010 to December 2017 were enrolled in this study. Data were collected retrospectively. Our primary outcome was ALI and its effect on hospital mortality. Secondary outcomes included six-month mortality, length of hospital stay, as well as other complications (stroke and renal failure) multivariate logistic regression analysis was used to identify predictors of ALI and hospital mortality. Results There were 71 patients included in this study. The overall VA ECMO hospital mortality was 53.5%. ALI was seen in 14 (19.7%) patients. Of these, four (5.6%) patients had fasciotomy, four patients (5.6%) had thrombectomy, and one underwent arterial repair (1.4%). Five additional patients (7.0%) with ALI expired and had no vascular intervention. None of the demographic and clinical characteristics significantly correlated with ALI except for stroke and renal failure requiring new onset hemodialysis (HD). The rate of hospital and 6-month mortality in patients with and without vascular complications were 78.6%, 92.3% and 47.4%, 57.4% respectively (p=0.042 and p=0.023). Multivariate analysis correlated hospital and six month mortality with ALI, stroke, and new onset HD. Conclusions ALI correlates with higher mortality in VA ECMO patients with femoral cannulation. Although, some of the contributing factors to mortality in these patients are related to the consequences of cardiopulmonary failure, strong efforts should be made to avoid ALI after femoral VA ECMO cannulation.