Results of extracorporeal life support implementation in routine clinical practice: single center experience

Review of anticoagulation considerations in extracorporeal membrane oxygenation support

Since its first success in 1975, extracorporeal membrane oxygenation (ECMO) has been used with increasing frequency for pulmonary and cardiopulmonary bypass. Use in adults has increased exponentially since the early 2000s, but despite thousands of international cannulations using both veno-arterial (VA) and veno-venous (VV) ECMO, there are still significant hemocompatibility-related adverse events. Current management of anticoagulation has been based on the Extracorporeal Life Support Organization guidance published in 2014 with recent updates published in 2022. Despite this guidance, there is still limited international consensus on how to manage anticoagulation in ECMO. For this review, we completed a comprehensive search of multiple electronic databases to identify studies pertaining to anticoagulation of adult patients on VV or VA-ECMO. The highest priority was given to sources that were prospective, randomized, controlled studies, but in the absence of such resources, observational studies, retrospective uncontrolled studies, and case series/reports were considered for inclusion. This document serves to provide a comprehensive review of the current understanding of management pertaining to anticoagulation relating to ECMO.

Clinical outcomes in patients after extracorporeal membrane oxygenation support for post-cardiotomy cardiogenic shock: a single-centre experience of 92 cases

OBJECTIVES

Post-cardiotomy cardiogenic shock is a major concern in cardiac surgery. We reviewed our experience of extracorporeal membrane oxygenation (ECMO) as temporary circulatory support in post-cardiotomy cardiogenic shock.

METHODS

Between January 2005 and December 2014, adult patients implanted with ECMO after cardiac surgical procedures were included. Indications for ECMO were failure to be withdrawn from cardiopulmonary bypass or refractory cardiogenic shock occurring during postoperative Days 1 and 2. Patients' characteristics and outcomes were prospectively collected in a local ECMO database.

RESULTS

Ninety-two patients, median age of 63 years (17-83 years), were supported by ECMO following valvular surgery (66%), acute aortic dissection (10%) and coronary artery bypass grafting (9%). A total of 37% were combined surgical procedures, 24% were redo procedures and 33% were emergent procedures. The median duration of ECMO support was 6 days (1-28 days). The weaning rate from mechanical support was 48%. Overall 1-month and 6-month survival rates were, respectively, 42% and 39%. Survivors were younger (57 vs 63 years old, P = 0.02) and had a higher preoperative left ventricular ejection fraction (52.5 vs 44.1%, P = 0.017). There was a trend for lower serum creatinine levels and total bilirubin rates in the survivors' group 24 h after initiation of ECMO (respectively, 162 vs 212 µmol/l, P = 0.06; 25.3 vs 54.2 mg/dl, P = 0.08). Valvular surgery and peak lactic acid serum level were associated with poor outcomes. The mean health-related quality of life EuroQoL scale was 68 ± 16/100 at 2 years.

CONCLUSIONS

Refractory cardiogenic shock requiring ECMO was most frequently observed after redo valvular surgery in the present study. The overall 6-month survival rate was 39% after ECMO support for post-cardiotomy cardiogenic shock with acceptable health-related quality of life. Improved kidney and liver functions after 24 h of support were associated with favourable outcomes.

Anticoagulation practices and the prevalence of major bleeding, thromboembolic events, and mortality in venoarterial extracorporeal membrane oxygenation: A systematic review and meta-analysis

PURPOSE

The purpose was to evaluate the safety of anticoagulation in venoarterial extracorporeal membrane oxygenation (VA-ECMO).

DESIGN

We performed a systematic review and meta-analysis using multiple electronic databases. Studies were from 1977 to September 27, 2016. We evaluated the effect of anticoagulation in VA-ECMO on outcomes including major bleeding, thromboembolic events, and in-hospital mortality using a random effects model meta-analysis.

RESULTS

Twenty-six studies (1496 patients) were included. Ten studies only had patients with postcardiotomy shock, 4 studies only included extracorporeal cardiopulmonary resuscitation patients, and 10 studies had a mixture of patients. Most studies (n=17) were low quality with a Newcastle-Ottawa Scale score ≤5. The summary prevalence of major bleeding was 27% (95% confidence interval [CI], 18%-35%), with considerable between-study heterogeneity (I²=91%). Major bleeding requiring reoperation was the most common bleeding event. The summary prevalence of thromboembolic events was 8% (95% CI, 4%-13%; I²=83%). Limb ischemia, circuit-related clotting, and stroke were the most commonly reported events. The summary prevalence for in-hospital mortality was 59% (95% CI, 52%-67%; I²=78%).

CONCLUSIONS

The optimal targets and strategies for anticoagulation in VA-ECMO are unclear. Evaluation of major bleeding and thromboembolic events is limited by study quality and between-study heterogeneity. Clinical trials are needed to investigate the optimal anticoagulation strategy.