An Audit of Extracorporeal Membrane Oxygenator (ECMO) Outcomes in Low Cardiac Output Syndrome Patients at Charlotte Maxeke Johannesburg Academic Hospital

Abstract

Introduction ECMO is a mechanical device that supports an inefficient cardiorespiratory system, including the state of LCOS (common after cardiopulmonary bypass), which is refractory to medical treatment. Centers globally have investigated its outcomes. Our center has used ECMO since the mid-1990s, but the associated outcomes must be examined. Study Aims and Objectives This study aims to evaluate the 30-day survival results and associated predictive factors of patients with low cardiac output syndrome who utilized ECMO after undergoing open heart surgery. Methodology It is a retrospective review of adult patients' records of ECMO within 72 hours following open heart surgery from November 2016 until the end of December 2022. Data collection and analysis were focused on patient demographics, surgical risk scoring, and preoperative and perioperative clinical factors. Continuous data was analyzed using a one-way ANOVA for descriptive analysis. The association of patient characteristics and outcomes was investigated using Fischer’s exact test. Statistical analysis was conducted using Stata® 18.0 Edition. Results: Of 1131 patients undergoing heart surgery within the period above, 3.36% utilized ECMO, and approximately 16% of the ECMO patients survived to discharge. 30-day mortality occurred in all 32 (84%) patients. Morbidity while on ECMO was evident in 100% of the patients. All surviving patients survived more than 30 days and were discharged from hospital. 100% of the ECMO connection was venoarterial, but 5 (13.5%) patients had peripheral cannulation. All patients with preoperative IABP demised. Normal preoperative urea and creatinine showed double the number of survivors than abnormal urea and creatinine. Conclusion: Our ECMO survival following open heart surgery is low (<16%), which is less than other well-established centers. Furthermore, factors for the poor outcomes are multifactorial (presence of preoperative IABP, older age, high surgical risk score, prolonged intraoperative time, coronary artery bypass, postoperative bleeding, sepsis, organ dysfunction, and failure to wean off ECMO).