Selective Distal Perfusion and Small Arterial Cannula Use Can Minimize Limb Ischemia Requiring Surgery in Patients in Femoral Veno-Arterial Extracorporeal Life Support.

Patients on femoral veno-arterial extracorporeal life support (VA-ECLS) are at risk of distal lower-limb hypoperfusion and ischemia of the cannulated leg. This study sought to evaluate the effect of using continuous non-invasive lower-limb oximetry with near-infrared reflectance spectroscopy (NIRS) to detect tissue hypoxia and guide distal perfusion catheter (DPC) placement on rates of leg ischemia requiring surgical intervention. We performed a retrospective analysis of patients placed on femoral VA-ECLS at our institution between 2010-2014 (pre-NIRS era) and 2017-2021 (NIRS era). Patients cannulated during the 2015-2016 transition era were excluded. Baseline characteristics, short-term outcomes, and ischemic complications requiring surgical intervention (fasciotomy, thrombectomy, amputation) were compared across the two cohorts. Of the 490 patients included in the study, 141 (28.8%) and 349 (71.2%) were cannulated before and after the routine use of NIRS to direct DPC placement, respectively. Patients in the recent cohort had greater rates of hyperlipidemia (53.7% vs 41.1%, P = 0.015) and hypertension (71.4% vs 60.0%, P = 0.020) at baseline, though they were less likely to have been supported with an intra-aortic balloon pump prior to ECLS cannulation (26.9% vs 37.6%, P = 0.026). These patients were also more likely to have cardiac arrest (22.9% vs 7.8%, P = <0.001) and pulmonary causes (5.2% vs 0.7%, P = 0.040) as indications for ECLS, with lower rates of ECLS initiated for acute myocardial infarction (15.8% vs 34.0%, P = <0.001). Patients in the NIRS cohort had a smaller arterial cannula size (P = <0.001) and greater duration of ECLS support (5.00 vs 3.25 days, P = <0.001) though significantly lower rates of surgical intervention for limb ischemia (2.6% vs 8.5%, P = 0.007) despite comparable rates of DPC placement (49.1% vs 44.7%, P = 0.427), with only 2 patients (1.1%) not identified by NIRS ultimately requiring surgical intervention. The use of smaller arterial cannulas (≤ 15 Fr) and continuous NIRS monitoring to guide selective insertion of DPCs may be a valid and effective strategy associated with a reduced incidence of ischemic events requiring surgical intervention. [ABSTRACT FROM AUTHOR]