Profile and Predictive Factors of Postoperative Lactic Acidosis in Pediatric Cardiac Surgery Under Extracorporeal Circulation

Abstract

This retrospective study analyzed the profile and predictors of lactic acidosis (LA) in 32 pediatric patients (ages 0-18) following cardiac surgery under cardiopulmonary bypass (CPB). LA was defined as arterial lactate > 2 mmol/L with pH < 7.35 upon ICU admission. Data included demographic, preoperative (EF, TAPSE, creatinine), and intraoperative parameters (CPB duration, cross-clamp time, vasoactive amines). Statistical analysis sought correlations between these factors and LA occurrence. The incidence of LA was 15.6% (5/32). The cohort (mean age 9.8 years, 65.6% male) showed preserved preoperative cardiac function. Surgery was equally split between valvular and congenital heart disease. Mean CPB duration was 110 minutes, with hypothermia used in 81.3% of cases and sympathomimetics in 78.1%. Analysis revealed no significant association between LA and demographic factors, preoperative parameters, or intraoperative data (type of surgery, CPB/clamp duration, amines). However, a non-significant trend showed 4 out of 5 LA cases occurred after congenital heart surgery. Clinically, LA was significantly correlated with a longer ICU stay (mean 3.75 vs. 2.77 days). No significant link was found with overall mortality (6.3%). In this pediatric series, postoperative lactic acidosis, while relatively infrequent, is associated with prolonged ICU stays. The absence of clear preoperative or intraoperative risk factors highlights the multifactorial complexity of this metabolic complication, necessitating vigilant postoperative monitoring.