2: Surgical Cutdown and Semi Seldinger Technique for Placement of Distal Perfusion Cannula after Percutaneous Cannulation in VA ECMO - Our Experience

Background: Extracorporeal Membrane Oxygenation (ECMO) is a life-saving intervention for patients with severe cardiorespiratory failure unresponsive to standard treatment. Femoral vessel cannulation via a percutaneous approach is commonly used due to its minimal invasiveness and rapid setup; however, it can result in limb ischemia in 10-70% of cases1-3. To mitigate this risk, a distal perfusion cannula (DPC) is often placed to maintain blood flow to the lower limb, but placement becomes challenging after main arterial cannulation, especially in patients experiencing circulatory shock. We assessed the technical feasibility, efficacy, and time required for DPC placement using surgical dissection and the semi-Seldinger technique under direct vision in complex cases. Method: When initial guide-wire placement via the superficial femoral artery (SFA) fails under ultrasound guidance, the ECMO physician proceeds with percutaneous cannulation of the common femoral artery (CFA) to initiate ECMO. Within 1-2 hours, a vascular surgeon then dissects the SFA and places a 6-8Fr DPC using the semi-Seldinger technique under direct vision. The DPC is connected to the side port of the main arterial cannula to maintain distal limb perfusion at a rate of 150-200 ml/min. Limb perfusion is closely monitored by clinical assessments viz. warmth, colour, and joint stiffness and also by Doppler ultrasound. Results: Among 23 cases where initial DPC placement was unsuccessful, ECMO initiation was delayed by about 30 minutes. The surgeon required less than 15 minutes to dissect the SFA and complete DPC placement within 5 minutes and achieved limb perfusion immediately without any procedural complications such as bleeding, hematoma, or infection. Conclusion: In urgent ECMO cases with difficult vascular access in patients experiencing shock, primary CFA cannulation followed by SFA dissection and DPC placement via the semi-Seldinger technique is effective. This approach minimizes ischemic and vascular complications, achieving timely limb perfusion in a safe manner.