Hyperlactatemia and its adverse patient outcomes among patients who underwent cardiopulmonary bypass surgery at national cardiac centre Addis Ababa, Ethiopia 2021. Retrospective observational study

Background: Hyperlactatemia and lactic acidosis are commonly encountered during and after cardiac surgery. Hyperlactatemia is highly suggestive of tissue ischemia and is associated with a prolonged intensive care unit stay, a prolonged requirement for respiratory and cardiovascular support, and increased postoperative mortality. Objective: To assess hyperlactatemia and adverse outcomes among patients who underwent cardiopulmonary bypass surgery at Cardiac Center Ethiopia, Addis Ababa, Ethiopia, 2021. Method: An institution-based retrospective cross-sectional study was employed among all patients who underwent cardiopulmonary bypass surgery from December to January 2020. Blood lactate samples were collected intraoperatively and postoperatively. We entered the collected data into Epidata version 4.2 and export it to SPSS 25 for analysis. We did descriptive statistics for categorical and continuous variables and chi-square to show an association between the outcome variable and independent variables. We entered variables fitted in bivariate analysis into multivariable analysis to show the strength of the association and the statistically significant variable. Result: The prevalence of hyperlactatemia in this study among patients who underwent cardiac surgery procedures at Cardiac Center Ethiopia was 37.5 %. A rise in lactate level prolongs ICU stay, prolongs intubation duration, and increases the need for Inotropes support. Lactate level was measured on the immediate postoperative day within 10 hours after the surgery and was defined as lactate level > 3 mmol/L in the first hour after surgery. Age > 40 years [AOR: 6.8 (95% CI 1.7-25), P=<0.008]. female gender [AOR: 1.8 (95% CI 1.1-3.8), P=0.048]. Variables statistically significant were declared at 95 % CI, p-value < 0.05. Conclusion and Recommended: An early rise in lactate levels in patients who underwent cardiopulmonary bypass surgery is a strong and robust predictor of morbidity. As a result, screening of patients in the preoperative period and strict follow-up management of those factors is recommended.