The information about the impact of preoperative dehydration on postoperative outcome is conflicting. One of the reported difficulties of the studies in this field is to get adequate power for statistical significance. The incidence of preoperative dehydration in different surgical populations has been reported in about one third of patients. The prevalence in the urologic population is not known.~This is a monocentric observational study with no study intervention. The goal is to consecutively include all patients undergoing major urologic surgery during 365 days who meet the inclusion criteria to assess the prevalence of preoperative dehydration in elective major abdominal urologic surgery when the standard operation procedures of the University Hospital Bern are applied.
The primary objective of this study is to measure the prevalence of preoperative dehydration in elective major abdominal urologic surgery when we apply our daily standard operation procedures. Secondary objectives are to assess the impact of preoperative dehydration on postoperative outcome. The hypothesis is that preoperative dehydration leads to more postoperative complications.