Comparison of 13Fr versus 15Fr arterial return cannula for V-A ECMO in ECPR

<b>Background:</b> Lower extremity ischemic complications of peripheral veno-arterial (VA) ECMO are common and variably reported across studies due to differences in definitions and distal perfusion practices, and are influenced in part by arterial cannula size.1,2 Typical arterial return cannula sizes used for adult ECPR are 17Fr or 15Fr.3. <b>Purpose:</b> We hypothesized that reducing arterial cannula size from 15Fr to 13Fr may reduce the need for distal perfusion catheter (DPC) placement for suspected cannula-associated threatened limb ischemia while maintaining adequate flows to support patients requiring ECPR. <b>Research Design and Study Sample:</b> We conducted a retrospective cohort analysis evaluating 39 adult ECPR patients at our center, comparing outcomes between those receiving 13Fr (<i>n</i> = 18) versus 15Fr (<i>n</i> = 21) arterial cannulas (Medtronic Bio-Medicus). <b>Analysis:</b> The primary endpoint was the rate of DPC placement for suspected cannula-associated limb ischemia. Secondary endpoints included ECMO flow parameters, illness severity markers, support duration, and 30-days survival. <b>Results:</b> The rate of DPC placement was significantly lower in the 13Fr group (16.7%) compared to the 15Fr group (47.6%, <i>p</i> = 0.04). There were no significant differences observed in survival rates, illness severity markers, or support duration between cohorts. <b>Conclusions:</b> These findings support the feasibility of smaller arterial cannulas as a strategy to reduce the need for additional limb reperfusion procedures in select ECPR patients.