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

Abstract

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 Indications for ECMO were failure to be withdrawn from cardiopulmonary bypass or refractory cardiogenic shock occurring during postoperative Days 1 and 2.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.

Keywords: Cardiac surgery; Cardiogenic shock; Extracorporeal membrane oxygenation; Survival analysis.