Variables predicting adverse outcome in patients with deep sternal wound infection

Background . Mortality after deep sternal wound infection (DSWI) ranges between 5% and 47%. Variables predicting hospital mortality and prolonged hospital stay are still to be assessed. Methods . Among 13,420 patients who underwent cardiac surgery in our institution between 1979 and 1999, DSWI developed in 112 cases (0.8%). Multiple variables were recorded prospectively and analyzed retrospectively as predictors of hospital death and prolonged (>30 days) hospital stay. The analyzed variables were divided into three groups: (1) related to the patient, including demographic variables and preoperative conditions; (2) related to cardiac operation; and (3) related to infection. Predictive variables were assessed by univariate and multivariate logistic regression analysis. Results . Hospital mortality was 16.9%. The hospital stay of the 93 discharged patients ranged between 16 and 180 days (mean 31.3 ± 15.2). Length of cardiac operation, length of stay in intensive care unit, interval between symptoms of DSWI and wound debridement were found to be the most significant predictors of bad outcome following DSWI. Conclusions . In our study demographic variables and preoperative conditions did not affect the prognosis of DSWI. Lower mortality rate and shorter hospital stay could be achieved with earlier and aggressive treatment of DSWI.