Perioperative neutrophil to lymphocyte ratio as a predictor of poor cardiac surgery patient outcomes

Abstract

PURPOSE: The purpose of the present study was to investigate the association between the perioperative neutrophil to lymphocyte ratio (NLR) and cardiac surgery patient outcomes. PATIENTS AND METHODS: A retrospective cohort study of 145 patients who underwent cardiac surgery in a tertiary hospital of Athens, Greece, from January to March 2015, was conducted. By using a structured short questionnaire, this study reviewed the electronic hospital database and the medical and nursing patient records for data collection purposes. The statistical significance was two-tailed, and p-values <0.05 were considered significant. The statistical analysis was performed with Mann-Whitney U test and Spearman's correlation coefficient, by using the Statistical Package for Social Sciences software (IBM SPSS 21.0 for Windows). RESULTS: The increased preoperative levels of NLR were associated with significantly higher mortality, both in-hospital (p=0.001) and 30-day (p=0.002), prolonged postoperative hospital length of stay (LOS), both in the cardiac intensive care unit (ICU) (p=0.002), and in-hospital (p=0.018), and likewise with delayed tracheal extubation (p