[Etiology and consequences of postoperative wound infection]

The incidence of postoperative wound infection ranges between 4.6% and 36% after gastrointestinal operations respectively. To evaluate the factors which influence the postoperative wound infection we prospectively analyzed our patients between 1/1989 and 1/1990. 444 patients from three general surgical units of our clinic entered this study. The overall wound infection rate was 6.3%. We classified the patients into 3 operative groups: Group I: subcutaneous operations; Group II: intraabdominal operations without opening the GI-tract; Group III: gastrointestinal operations. Wound infection rate in group I was 1.8%, in group II 7.3% and in group III 13.7%. The differences were highly significant. Both univariate (chi 2-test) as well as a multivariate (Cox-Model) analysis were done. We figured out that classification of patients (p = 0.000), operation time (p = 0.009), operating room (p = 0.000), intensive care unit (p = 0.026), long-term antibiotic prophylaxis (p = 0.001), subcutaneous haematoma (p = 0.000) and length of closed drainage time (p = 0.001) are of significant value. In the Cox model the classification of patients into 3 groups surpassed all the other factors. Postoperative hospital stay was lengthened in patients with wound infection significantly (p = 0.0025).