Prevalence of Preoperative Dehydration in Major Elective Urologic Surgery and Its Impact on Postoperative Outcome

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Prevalence of Preoperative Dehydration in Major Elective Urologic Surgery and Its Impact on Postoperative Outcome

Conditions
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Dehydration, Postoperative Nausea and Vomiting, Postoperative Complications

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: >18 years old Major elective urologic surgery i. Prostate surgery ii. Bladder surgery iii. Kidney surgery iv. Various laparotomies / laparoscopies (e.g. retroperitoneal lymphadenectomy) Standard procedure planned Standard perioperative management planned Informed consent Exclusion Criteria: Preoperative iv-fluids Pregnancy (which is a contraindication to this type of surgery per se) Inability to give informed consent (e.g. severe psychiatric disorder, dementia) Inability to complete the Quality of Recovery (QoR) questionnaire Enrolment of the investigator, his/her family members, employees and other dependent persons

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of Dehydration at Induction of Anesthesia | Number of dehydrated patients judged by urine specific gravity, osmolality, creatinine, color. | Time point 0: time (estimated between 7am and 4pm on day of surgery) at Induction of Anesthesia for Major Urologic Surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Nausea and Vomiting (PONV) | Number of patients with postoperative nausea and/or vomiting at 6, 24 and 48 hours postoperatively. | 6 hours, 24 hours and 48 hours postoperatively | 
| Gastrointestinal function (flatus/defecation) postoperatively | Time of first flatus or defecation | 24 hours and 48 hours postoperatively | 
| Renal function postoperatively | Creatinine 6, 24 and 48 hours postoperatively. | 6 hours, 24 hours and 48 hours postoperatively | 
| Fluid balance | Judged by administered and lost fluids intraoperatively and by weight balance on postoperative day (POD) 1. | within 24 hours postoperatively | 
| Complications within hospitalization | Number of complications according to a prospective list | within hospital stay, expected to be within 2 weeks postoperatively | 
| Quality of recovery | Changes in Quality of Recovery using the validated 15 items quality of recovery (QoR-15) score : QoR is a patient reported outcome short questionnaire that measure the quality of recovery after surgery and anaesthesia. It incorporates 5 dimensions of health (patient support, comfort, emotions, physical independence, pain). This is a shortened validated version of the QoR 40 including 15 items. QoR-15, with a score range from 0 to 150 (0 worst possible, 150 best possible), is easy to perform. Recently a meta-analysis showed that QoR 15 fulfils requirements for outcome measurement instruments. | 24 hours postoperatively |