Enhanced preoperative C-reactive protein plasma levels as a risk factor for postoperative infections after cardiac surgery

Background. We examined the possible predictive role of preoperative C-reac tive protein (CRP) levels for postoperative infections in patients who have cardiac operations. Methods. CRP levels were determined on the day before the operation and on postoperative days 1 to 4 and 6 in 593 consecutive patients. Furthermore, w e documented infectious disease-related data. Results. Patients in whom an infection developed during the postoperative c ourse (n = 87) had significantly higher CRP levels on the day before operat ion (17.8 +/- 3.9 mg/L compared with 7.7 +/- 0.7 mg/L; p < 0.001) and on po stoperative days 4 and 6. The incidence of postoperative infections was sig nificantly higher in patients with increased preoperative CRP levels than i n those with normal preoperative CRP levels (25.3% versus 11.2%, respective ly; p < 0.001). Furthermore, patients with higher preoperative CRP levels h ad a significantly longer postoperative hospital stay than those with norma l preoperative CRP levels (10.8 +/- 1.2 days versus 7.8 +/- 0.3 days; p < 0 .001). Multivariate analysis, including classic risk factors and increased preoperative CRP levels, demonstrated that higher preoperative CRP was the most important variable predicting postoperative infection (odds ratio = 2. 7; 95% confidence interval = 1.7 to 4.3; p < 0.001). Conclusions. Patients with higher preoperative CRP levels are at increased risk for postoperative infections. Therefore, preoperative measurement of C RP might be a useful, predictive marker in risk stratification for postoper ative infections in patients scheduled for cardiac operations. (C) 1999 by The Society of Thoracic Surgeons.