Extracorporal membrane oxygenation for cardiopulmonary support after open heart surgery

Introduction

Arterial-venous extracorporal membrane oxygenation (ECMO) is a rescue tool in acute heart failure after cardiopulmonary bypass (CPB) when separation from CPB cannot be achieved by conventional means (volume, inotropes, intra-aortic counterpulsation IABP). The role of ECMO in this scenario is far from clear and factors predicting a poor outcome are lacking. However, such indices would be helpful to find a reasonable approach.

Methods

Analysis of a prospective evaluated dataset in a surgical ICU of a university teaching hospital.

Results

In 19 patients (mean age 58 years) with postcardiotomy cardiogenic shock despite high-dose medication with inotropes and normal filling pressures, separation from CPB was not possible. These patients were scheduled for ECMO. The mean preoperative EF was 20.8% and in 47.3% of the patients cardiopulmonary resuscitation (CPR) had to be performed already before CPB. Eleven patients (57.8%) received an IABP before ECMO. The most frequent complications in the ICU were: arrhythmia (63.1%), bleeding (78.9%), renal failure with CRRT (47.3%) and respiratory failure (paO₂/FiO₂ < 250 mmHg) (100%). The mean duration on ECMO was 6.8 days, mean stay in the ICU was 13.1 days and mean hospital stay was 44.5 days. Only 6/19 patients survived (31.5%) and were discharged from hospital. These patients except one had no CPR in the preoperative period.

Conclusions

ECMO in acute heart failure after adult open heart surgery in this series had an enormous high mortality of 68.5%. However, these results are in line with other series with a reported mortality of 67 to 75.2% [1, 2]. CPR in the preoperative setting seems to be a grave sign for survival and in these patients ECMO is not recommended since mortality reaches an unacceptable high rate. This statement needs to be confirmed by an adequate powered trial.