Lymphocyte Levels and Morbidity and Mortality in Cardiovascular Surgery With Cardiopulmonary Bypass.

Introduction: A year ago, in a sample of 113 patients, our research group found that a high number of lymphocytes in the immediate postoperative period was correlated to a poor prognosis in cardiovascular surgeries. This study is an expansion of the initial study in order to confirm this finding.

Methods: We analyzed the data of 338 consecutive patients submitted to cardiovascular surgeries with cardiopulmonary bypass performed at Hospital Universitário Ciências Médicas (Belo Horizonte/Brazil) from 2015 to 2017. We analyzed 39 variables with the outcomes death, hospital stay, and intensive care unit stay.

Results: The value of lymphocytes in the immediate postoperative period > 2175.0/mm³ was an indicator of poor prognosis in this sample (P<0.001). The variables female sex, age, high level of European System for Cardiac Operative Risk Evaluation II, increased stay in the intensive care unit and in the ward, elevation of creatinine in the preoperative period and at intensive care unit discharge, elevation of the percentage of immediate postoperative period segmented neutrophils, high immediate postoperative period neutrophil/lymphocyte ratio, fasting hyperglycemia, preoperative critical condition, reintubation, mild or transient acute renal failure, surgical infection, cardiopulmonary bypass, and aortic cross-clamping and mechanical ventilation durations also had an impact on the mortality outcome.

Conclusion: The value of lymphocytes in the immediate postoperative period > 2175.0/mm3 was an indicator of poor prognosis in cardiovascular surgery with cardiopulmonary bypass.