Preoperative prediction of postoperative edema and effusion in pediatric cardiac surgery by altered antigen expression patterns on granulocytes and monocytes

Postoperative edema and effusion (POEE) following cardiopulmonary bypass (C PB) surgery in children retards recovery and may aggravate postpericardioto my (PPS), capillary leak syndrome (CLS), or multiorgan failure (MOF). Compa red with complication-free children, POEE affected children have different preoperative serum levels of circulating cytokines and adhesion molecules. These levels may be used preoperatively to assess POEE, but their determina tion is time consuming, costly, and a substantial blood volume is required. Altered serum levels of cytokines and adhesion molecules also may be refle cted in altered antigen expression an circulating blood leukocytes. The pre dictive potential of flow cytometric (FCM) leukocyte immunophenotyping was explored as a sensitive and fast method that required small blood samples. Blood samples taken 24 h preoperatively from 49 patients (3-18 years old) w ere stained with monoclonal antibodies for adhesion molecules ([CAM-1, LFA- 1, Mac-1) or constitutive/activation markers (CD4, CD14, CD16, CD25, CD54, CD69, HLA-DR) and measured on a microbead calibrated FCM. Neutrophils, mono cytes, and eosinophils from POEE patients express higher preoperative level s of LFA-1, monocytes, HLA-DR, and other activation markers (all P < 0.03). Over 89% of the patients were classified correctly by using two discrimina nt analysis methods (sensitivity, > 76%; specificity, > 86%; positive predi ction, > 80%; negative prediction, > 83%). Granulocytes and monocytes of po stoperative POEE patients exhibit significant preoperative immune activatio n, suggesting an increased risk for patients with atopic/allergic predispos ition. Surgical trauma and CPB cause additional immune activation, leading to POEE by a summative response. Most patients at risk for POEE can be iden tified preoperatively by using data pattern analysis on FCM-derived paramet ers. (C) 2001 Wiley-Liss, Inc.