Vasopressin as an etiologic factor for infection in gynecologic surgery: A randomized double-blind placebo-controlled trial

Objective: The purpose of this study was to evaluate the risk of pelvic infection with the use of vasopressin at time of vaginal hysterectomy with a randomized controlled trial. Study Design: Women who underwent vaginal hysterectomy and agreed to participate were randomly assigned to pericervical injections of vasopressin or normal saline solution. Surgeons and patients were blinded to the injected substance. Power analysis revealed that a sample size of 116 patients would be sufficient to detect a 4-fold difference in pelvic infection rates between the 2 groups, with 90% power and a probability value of .05. Results: Analysis with 117 patients found no difference in infection rate between the normal saline solution group and the vasopressin groups (7.3% vs 1.6%; P = .19). Estimated blood loss (312 ± 222 mL vs 446 ± 296 mL; P = .006) and change in hemoglobin and hematocrit levels (2.1 ± 1.4 gm vs 2.9 ± 1.4 gm; P: = .02; and 6.7% ± 3.4% vs 8.5% ± 3.8%; P = .01; vasopressin versus normal saline solution, respectively) were significantly less in the vasopressin group. There were no significant differences in interval blood pressure measurements after vasopressin administration between the 2 groups. Conclusion: The use of vasopressin during vaginal hysterectomy does not increase the risk of pelvic infection, does decrease operative blood loss, and does not significantly affect blood pressure. (Am J Obstet Gynecol 2001;185:1344-8.)