Abstract
Background Recirculation during veno-venous extracorporeal membrane oxygenation (VV-ECMO) is a known drawback that limits sufficient oxygenation. This study aimed to compare the short-term oxygenation and long-term mortality based on cannula configuration in patients with acute respiratory distress syndrome (ARDS) who receive VV-ECMO, especially in the absence of newly developed double-lumen, single cannula.Methods Data of patients with severe ARDS who received VV-ECMO from 2012–2015 at six hospitals were retrospectively analyzed. Primary outcomes were the partial pressure of oxygen (PaO 2 ) at 1, 4, and 12 hours after ECMO initiation and 180-day mortality.Results Patients ( n = 354) were divided into two groups based on the return cannula site: femoral vein ( n = 193) or internal jugular vein ( n = 161). Baseline characteristics at admission, including PaO 2 , were similar between the groups. PaO 2 at 1 hour after ECMO initiation was higher in the femoral than in the jugular group (190.3 vs. 160, P = 0.108). No significant increase in PaO 2 occurred at 4 and 12 hours between the groups. PaCO 2 decrement at 4 hours was lower in the jugular than in the femoral group (36.4 vs. 33.7 mmHg, P = 0.009). The two groups did not differ in terms of mortality at 180 days after ECMO, however more cannula related complications occurred in the jugular group.Conclusion Regardless of the cannula configuration, patients with ARDS managed with VV-ECMO showed comparable clinical outcomes in terms of short-term oxygenation and long-term mortality. Nevertheless, further well-designed randomized control trials are warranted.