Arterial Vascular Complications in Peripheral Venoarterial Extracorporeal Membrane Oxygenation Support.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) has been evolved as a life-saving measure for patients requiring emergent support of respiratory and cardiac function.The femoral artery is the standard site for vascular access when initiating adult venoarterial (VA) ECMO.Cannulation-related complications are a known source of morbidity and it has been speculated that patients undergoing ECMO via femoral arterial cannulation are more likely to develop peripheral vascular complications (up to 70%). In patients with severe peripheral arterial disease (PAD) these risks are even higher and its presence may be considered a relative contraindication for femoral artery cannulation.

METHODS: Retrospective institutional review of patients requiring ECMO (January 2011-August 2017).The primary outcome of this study was to investigate the prevalence of cannulation- -related complications on VA ECMO and to determine its effect on patient morbimortality.We evaluated demographics and co-morbidities data.Patients were divided into two groups (complications present VS not present) and statistic analysis was performed to determine the impact of different variables such as co-morbidities,cannulation strategy and time on ECMO in each group.Operative reports were reviewed to analyze the surgical procedures implied for treating vascular complications.

RESULTS: Eighty-two patients underwent ECMO therapy during the period of study, 56,1% were male with a mean age of 55,8 years.The median time on the ECMO device was 5,5 days.The VA mode was used in 61 patients, 56 with peripheral cannulation.Femoral arterial access was established in 52 patients (73% percutaneously).Vascular complications were observed in 28,6% of the VA femoral ECMOs:12 acute limb ischemias and 3 major hemorrhages. At the time of femoral cannulation, distal peripheral catheter (DPC) was placed in 5 patients and none developed subsequent limb ischemia.For those who developed limb ischemia, several interventions were performed: DPC placement in 9 cases, fasciotomy in 4 and 2 major amputations. Thirty patients underwent arterial cannulas open surgical removal:8 underwent balloon catheter trombectomy and 5 needed femoral reconstruction.There was an association between PAD (p=0,03) and ischemic cardiopathy (p=0,02;OR 4,5) with the present of vascular complications after ECMO implantation.VA femoral ECMO mortality was 69,2% (n=36).Vascular complications after ECMO support are not associated with higher mortality rates (p>0,05).

CONCLUSION: Cannulation of femoral vessels remains associated with considerable rates of vascular events (28.6%).PAD and ischemic cardiopathy are associated with vascular complications in this form of cannulation.Physical examination and the assessment of ankle-brachial índex before ECMO implantation is therefore recommended.Improved efforts at preventing these complications need to be developed to avoid additional morbidity in an already critical patient population.