[Factors influencing the development of incisional hernia. A retrospective study of 2,983 laparotomy patients over a period of 10 years].

INTRODUCTION: Incisional hernia formation is one of the most frequent complications in visceral surgery requiring reoperation. Risk factors for incisional hernia formation and preventive strategies are not clearly defined.
METHODS: In a retrospective study including 2983 patients over a 10-year period, the influence of demographic data, pre-, intra- and postoperative risk factors for incisional hernia development were evaluated. From the subgroups medical history, medication, laboratory values, indication, surgical technique, course of operation, postoperative course and wound healing, altogether 43 parameters were analysed. Statistical evaluation was performed using the chi 2-test according to Pearson, and binary logistic regression analysis.
RESULTS: The mean incisional hernia incidence in the study was 4.3%. In the mean follow-up period of 21.1 months, the incisional hernia incidence was calculated at 9.8% using the Kaplan-Meier estimate; for a 10-year period it reached 18.7%. The study revealed that 31.5% of all incisional hernias developed in the first 6 months after the operation, 54.4% after 12 months, 74.8% after 2 years and 88.9% after 5 years. Significant demographic factors influencing incisional hernia incidence were age (> 45 years) and male gender. The preoperative factors anaemia (Hb < 100 g/l) and BMI > 25, the intraoperative factors recurrent incision and previous laparotomy, and the postoperative factors catecholamin-therapy and disturbed wound healing were of significant influence.
CONCLUSION: The calculated incisional hernia incidence for a 10 year period of almost 20% and the manifestation of 50% of all hernias more than 12 months after the operation, underline the necessity to intensify surgical research in the field of laparotomy healing. In comparison to demographic and endogenous risk factors, the surgical technique has less influence on laparotomy healing. Measures to ameliorate tissue perfusin seem to exert a positive influence on incisional hernia incidence.