ABSTRACT
OBJECTIVE: This study investigated the predictive value of a decrease in monocyte HLA-DR expression as an early marker for postoperative SIRS and septic complications. We hypothesized that decreased HLA-DR levels in the first 24 h after cardiac surgery is not related to postoperative SIRS/sepsis. We also compared HLA-DR levels of patients with postoperative complications to those with an uncomplicated course. DESIGN AND SETTING: Prospective observational study in a tertiary care postoperative intensive care unit. PATIENTS: Eighty five consecutive patients undergoing cardiac surgery. MEASUREMENTS AND RESULTS: Expression of HLA-DR on monocytes was analyzed by flow cytometry using a new quantitative and well standardized technique. Arterial blood samples were collected before induction of anesthesia, immediately after admission to the ICU, and on the first postoperative day. Postoperative HLA-DR expression was significantly decreased in all patients. There were no significant differences in HLA-DR expression during the first 24 h after surgery in patients with uncomplicated course and those developing SIRS or septic complications. CONCLUSIONS: In patients undergoing cardiac surgery the monitoring of pre- and immediate postoperative HLA-DR levels during the first 24 h does not help to predict increased risk for postoperative SIRS/sepsis or infectious complications.