Introduction: Limb ischemia is a severe complication of peripheral veno-arterial extracorporeal life support (V-A ECLS). Several techniques have been developed to prevent this, but it remains a major and frequent adverse event (incidence: 10-30%). In 2019, a new cannula with bidirectional flow (retrograde towards the heart and antegrade towards the distal limb) has been introduced. A single-centre experience with this cannula in patients undergoing peripheral V-A ECLS is herewith reported.
Methods: This prospective observational study included adults (≥18 years) undergoing V-A ECLS from January 2021 to October 2022 with the use of a bidirectional femoral artery cannula. Primary outcome was limb ischemia requiring intervention during cardio-circulatory support. Secondary outcomes were compartment syndrome, limb amputation, cannulation site bleeding, need for other surgical intervention due to cannula related complications, duplex ultrasound parameters from the femoral vessels, and in-hospital survival.
Results: Twenty-two consecutive patients were included. During extracorporeal life support (ECLS) support, limb ischemia requiring intervention occurred in one patient (4.5%) and no patients developed a compartment syndrome, or required a fasciotomy or amputation. Significant bleeding was reported in two patients (9%) due to slight cannula dislodgement, easily solved with cannula repositioning. In-hospital survival was 63.6%.
Conclusions: The bidirectional cannula is associated with a low risk for limb ischemia-related complications compared to current literature, and apparently represents a safe alternative to dedicated distal perfusion cannula. Further studies are warranted to confirm these preliminary findings.
Keywords: bi-flow; bidirectional; cannula; extracorporeal life support; extracorporeal membrane oxygenation; livanova; veno-arterial.