Femoro-axillary versus femoro-femoral veno-arterial extracorporeal membrane oxygenation for refractory cardiogenic shock: A monocentric retrospective study

RATIONALE

For veno-arterial extracorporeal membrane oxygenation (ECMO), the femoral artery is the preferred cannulation site (femoro-femoral: Vf-Af). This results in retrograde aortic flow, which increases the left ventricular afterload and can lead to severe pulmonary edema and thrombosis of the cardiac chambers. Right axillary artery cannulation (femoral-axillary: Vf-Aa) provides partial anterograde aortic flow, which may prevent some complications. This study aimed to compare the 90-day mortality and complication rates between VF-AA and VF-AF.

METHODS

Consecutive adult patients with cardiogenic shock who received peripheral VA-ECMO between 2013 and 2019 at our institution were retrospectively included. The exclusion criteria were refractory cardiac arrest, multiple VA-ECMO implantations due to vascular access changes, weaning failure, or ICU readmission. A statistical approach using inverse probability of treatment weighting was used to estimate the effect of the cannulation site on the outcomes. The primary endpoint was the 90-day mortality. The secondary endpoints were vascular access complications, stroke, and other complications related to retrograde blood flow. Outcomes were estimated using logistic regression analysis.

RESULTS

VA-ECMO was performed on 534 patients. Patients with refractory cardiac arrest (n = 77 (14%)) and those supported by multiple VA-ECMO (n = 92, (17%)) were excluded. Out of the 333 patients studied (n = 209 Vf-Aa; n = 124 VF-AF), the main indications for VA-ECMO implantation were post-cardiotomy (33%, n = 109), dilated cardiomyopathy (20%, n = 66), post-cardiac transplantation (15%, n = 50), acute myocardial infarction (14%, n = 46) and other etiologies (18%, n = 62). The median SOFA score was 9 [7-11], and the crude 90-day mortality rate was 53% (n = 175). After IPTW, the 90-day mortality was similar in the Vf-Aa and VF-AF groups (54% vs 58%, IPTW-OR = 0.84 [0.54-1.29]). Axillary artery cannulation was associated with significantly fewer local infections (OR = 0.21, 95% CI:0.09-0.51), limb ischemia (OR = 0.37, 95% CI:0.17-0.84), bowel ischemia (OR = 0.16, 95% CI:0.05-0.51) and pulmonary edema (OR = 0.52, 95% CI:0.29-0.92) episodes, but with a higher rate of stroke (OR = 2.87, 95% CI:1.08-7.62) than femoral artery cannulation.

CONCLUSION

Compared to VF-AF, axillary cannulation was associated with similar 90-day mortality rates. The high rate of stroke associated with axillary artery cannulation requires further investigation.

Determinants of Arterial Pressure of Oxygen and Carbon Dioxide in Patients Supported by Veno-Arterial ECMO

Background: The present study aimed to assess the determinants of arterial partial pressure of oxygen (PaO₂) and carbon dioxide (PaCO₂) in the early phase of veno-arterial extracorporeal membrane oxygenation (VA ECMO) support. Even though the guidelines considered both the risks of hypoxemia and hyperoxemia during ECMO support, there are a lack of data concerning the patients supported by VA ECMO. Methods: This is a retrospective, monocentric, observational cohort study in a university-affiliated cardiac intensive care unit. Hemodynamic parameters, ECMO parameters, ventilator settings, and blood gas analyses were collected at several time points during the first 48 h of VA ECMO support. For each timepoint, the blood samples were drawn simultaneously from the right radial artery catheter, VA ECMO venous line (before the oxygenator), and from VA ECMO arterial line (after the oxygenator). Univariate followed by multivariate mixed-model analyses were performed for longitudinal data analyses. Results: Forty-five patients with femoro-femoral peripheral VA ECMO were included. In multivariate analysis, the patients' PaO₂ was independently associated with Q_EC, F_DO₂, and time of measurement. The patients' PaCO₂ was associated with the sweep rate flow and the P_preCO₂. Conclusions: During acute VA ECMO support, the main determinants of patient oxygenation are determined by VA ECMO parameters.

Preclosing of the femoral artery allows total percutaneous venoarterial extracorporeal membrane oxygenation and prevents groin wound infection after lung transplantation

OBJECTIVES

In lung transplantation (LT), femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO) usually requires an open approach that may be associated with severe groin wound infection. In endovascular aortic procedures, preclosing of the femoral artery (PFA) with vascular closure devices allows the percutaneous insertion and withdrawal of large-bore cannulae. We sought to evaluate whether this innovative technique could be applied in the specific setting of LT to achieve total percutaneous VA-ECMO and decrease groin wound infection.

METHODS

We conducted a retrospective study of a prospective database including patients who underwent LT in our centre from January 2011 to December 2017. Patients who underwent peripheral VA-ECMO using the PFA technique after January 2014 (PFA group, n = 106) were compared to those who underwent peripheral VA-ECMO using open cannulation and/or decannulation before January 2014 (non-PFA group, n = 48). The primary end point was the rate of technical success defined as total percutaneous VA-ECMO. Secondary end points included groin wound infections and delayed vascular complications.

RESULTS

The PFA technique was technically successful in 98 patients (92.5%). As compared with the non-PFA group, the PFA group was characterized by a similar rate of vascular complications (16.6% vs 11.3%, P = 0.360) and a decreased rate of groin wound infection (18.9% vs 0%, P < 0.001). In multivariate analysis, risk factors associated with vascular complications following PFA included female sex, peripheral arterial disease and ECMO duration.

CONCLUSIONS

In LT patients, PFA is associated with a high rate of total percutaneous VA-ECMO, thus preventing the occurrence of groin wound infection.