STERNAL WOUND COMPLICATIONS - INCIDENCE, MICROBIOLOGY AND RISK-FACTORS

Objective: Sternal wound complications, i.e. instability and/or infect ion (mediastinitis), are important causes of morbidity in patients und ergoing cardiac surgery via median sternotomy. Coagulase negative stap hylococci, a normal inhabitant of the skin, have evolved as a cause of sternal wound infections. Since these opportunistic pathogens often a re multiresistant, they can cause therapeutic problems. Methods: From 1980 through 1995 open heart surgery, was performed on 13,285 adult pa tients. Reoperation necessitated by sternal wound complications occure rd in 203 patients (1.5%). The incidence was 1.7% (168/9987) after cor onary artery bypass grafting (CABG group) and 0.7% (35/3413) after hea rt valve surgery with or without concomitant CABG (HVR group). Results : Factors independently related to sternal complications in the CABG g roup (variable odds ratio [95% C.I.]): year of surgery, 1.9 [1.3-2.8] in 1990-1992, 2.0 [1.4-2.9] in 1993-1995; female sex, 0.4 [0.2-0.6]: d iabetic disease, 1.8 [1.2-2.5]: bilateral ITA procedure, 3.3 [1.1-7.7] ; and postoperative dialysis, 3.1 [1.4-6.9]. In the HVR group they wer e: use of ITA graft, 3.7 [1.7-7.7]; early re-exploration because of bl eeding 3.0 [1.1-8.2]; and postoperative dialysis 3.1, [1.4-9.3]. Multi variate models were used to compute the risk for sternal complications in each patient. However, the prognostic models based on these risk s cores provided low sensitivity and low predictive value. Patients with sternal wound complications showed no increased early mortality but w orse long-term survival even after adjustment for other factors (relat ive hazard in CABG group 1.9 [1.2-2.8]; in HVR group 2.1 [1.1-4.3]. Co nclusions: The use of ITA grafts seems to be one of the most important factors related to sternal wound complications. However, patients at truly increased risk for this complication could not be identified on the basis of the risk factors considered in this study. (C) 1997 Elsev ier Science B.V.