PREDICTIVE FACTORS OF SURGICAL INFECTION IN CARDIAC-SURGERY

BACKGROUND: Deep infection of the surgical site in cardiac surgery may lead to very severe complications. There is controversy as to the imp ortance which different factors may have in the incidence of this comp lication. The aim of this study was to determine the importance of det ermined factors on the risk of deep infection of the surgical site. ME THODS: A retrospective study of 1,127 patients submitted to cardiac su rgery from 1989 to 1991 was performed. The factors associated to the d evelopment of deep surgical infection were determined by univariant an alysis. A multiple logistic regression model was designed to identify the factors independently associated to the risk of infection. The mor bidity of surgical infection attributable to prolonged preoperative st ay was calculated. RESULTS: Of the numerous factors associated to risk of surgical site infection on univariant analysis, only five were ind ependently associated to risk of infection on multivariant analysis: p rolonged preoperative stay (OR = 2.4 [1.1-5.5]), dirty surgery (OR = 3 .2 [1.0-9.9]), length of the intervention (OR [every hour] = 1.5 [1.2- 2.0]), diabetes mellitus or chronic obstructive pulmonary disease (OR = 2.6 [1.2-5.6]) and functional grade according to the New York Heart Association (OR = 3.4 [1.5-7.7]). The proportion of deep infection att ributable to prolonged preoperative stay was 41.8% (4.0-58.2). CONCLUS IONS: The incidence of deep surgical infection may be decreased with a reduction, whenever possible, of the length of surgical intervention and preoperative stay.