Preoperative lymphopenia is a predictor of postoperative adverse outcomes in children with congenital heart disease

Objective: Lymphopenia is a predictor of adverse clinical outcomes in adults with various systemic diseases. We hypothesized that preoperative absolute lymphopenia (absolute lymphocyte count of less than 3000 cells/mu L) is associated with adverse postoperative outcomes in children with congenital heart disease undergoing corrective or palliative surgery on cardiopulmonary bypass during the first 2 years of life. Methods: A retrospective single center cohort study was performed. Categorical variables were analyzed with the chi(2) test. Preoperative variables were analyzed with logistic and linear regression analysis to determine whether they were associated with adverse outcomes. Results: Analysis was performed on 280 patients, of whom 124 were female and 156 were male. Seventy-one patients were neonates (<= 30 days) at the time of the operation. Ninety patients had an absolute lymphocyte count of less than 3000 cells/mu L before the operation. Regression models showed that RACHS-1 categories 5 and 6, age, and preoperative lymphopenia were significantly associated with postoperative mortality (P < .0006). Within RACHS-1 groups, lymphopenia remained a significant predictor of mortality for patients in RACHS categories 3 and 4. Lymphopenia and age were associated with longer length of stay and length of mechanical ventilation within RACHS categories 1 to 4 (P < .05). Preoperative lymphopenia was the only predictor of use of postoperative nitric oxide (P < .05). Conclusions: Preoperative lymphopenia is a predictor of adverse postoperative outcomes in children with congenital heart disease who undergo a corrective or palliative procedure with cardiopulmonary bypass during the first 2 years of life.