The impact of severity of initial illness, determined by SOFA score, and presence of anemia on outcomes among patients requiring Extra Corporal Membrane Oxygenation (ECMO) support: A single center experience

Abstract

Introduction: ECMO provides respiratory and circulatory support in critically ill patients. In our study, we report on a single center experience with ECMO and aim to identify the prognostic markers for survival to discharge from hospital. Methods: A registry was maintained on all patients who underwent ECMO implantation from September 2012 till January 2016 at a single institution. The collected data was analyzed to identify baseline characteristics, outcomes including clinical variables predictive of poor outcome. Results: A total of 29 patients underwent ECMO implantation. The average age of patients was 42 ± 18 years. 59% were males (N = 17). 19 cases had a cardiac indication for ECMO (66%) while 10 cases had a pulmonary indication (34%). On univariate analysis; presence of Multi-organ failure, SOFA score more than 18 and hemoglobin less than 10 g/dl at baseline and after ECMO removal were associated with increased 30 day mortality. Pearson correlation with 30 day mortality showed a positive correlation with MOF (+0.562, p = 0.002) and SOFA score >18 (+0.448, p = 0.015) and a negative correlation with anemia (−0.507, p = 0.005). 15 out of the total 29 patients (52%) died within 30 days of admission. Patients with MOF (log rank: 10.926, p = 0.001), SOFA score >18 (log rank: 7.758, p = 0.005) and hemoglobin <10 g/dl (log rank: 5.595, p = 0.018) had decreased survival on 30 day follow up. Conclusions: Although the use of ECMO as a last line in the treatment of critical patients refractory to conventional treatment measures constitutes an important improvement in their care; with 48% overall survival; patient selection and timing of ECMO initiation remains challenging. Patients who already had signs of MOF and a high SOFA score portended a poor response. Similarly for anemic patients. Hence the importance of consideration for ECMO use earlier in course of illness rather than later. Screening and aggressive treatment of anemia in those patients may help improve the outcomes.

Keywords

• Cardiogenic shock
• Adult respiratory distress syndrome
• Extra-corporal oxygenation
• SOFA score
• Multi-organ failure