Predictive risk factors of postoperative pneumonia after heart transplantation

Abstract

Background Pneumonia is a frequent complication in patients undergoing heart transplantation (HTx) which increases morbidity and mortality in this population. Nevertheless, risk factors of postoperative pneumonia (POP) are still unknown. The aim of this study was to investigate the predictive risk factors of POP in HTx recipients. Materials and methods In this retrospective study, all patients undergoing HTx between January 2014 and December 2015 were included. All POP occurring until hospital discharge were investigated. The primary end point was the risk factors of POP determined by a Cox model in uni- and multivariate analysis. Data are expressed in OR [95% CI]. P<0.05 was necessary to reject the null hypothesis. Results At all, 175 patients were included without any loss of follow-up and 89 POP were diagnosed in 59 (34%) patients. Enterobacteriaceae and Pseudomonas aeruginosa were mainly involved. In multivariate analysis, main risk factors were preoperative mechanical ventilation (OR 1.42[1.12-1.80], P<0.01) and perioperative blood transfusion (OR 1.42[IC95:1.20-1.70], P<0.01). Duration of mechanical ventilation, time of veno-arterial extracorporeal membrane oxygenation weaning and length of stay in intensive care unit consistently increased the risk of POP which impacted the mortality at 30 days (Odd Ratio: 4[1.3 - 12.4], P=0.01) and 1 year (OR: 6.8[2.5-8.4], P<0.01). In sensitized recipients (53%), plasmapheresis exchanges and intravenous immunoglobulins did not increase the risk of POP. Conclusion After HTx, preoperative mechanical ventilation and blood transfusion appear as the main risk factors of POP, enterobacteriaceae and Pseudomonas aeruginosa being mainly involved.