Pyridoxine Prevents Postoperative Nausea and Vomiting in Gynecologic Laparoscopic Surgery: A Double-blind Randomized Controlled Trial

Abstract

Background: Postoperative nausea and vomiting are common complications after gynecologic laparoscopic surgery. Pyridoxine has been recommended as a first-line drug to prevent and treat nausea and vomiting during pregnancy; however, its efficacy in preventing postoperative nausea and vomiting remains unclear.

Methods: Patients of 18 to 65 yr old who received elective gynecologic laparoscopic surgery under general anesthesia were randomized into either the pyridoxine group or the control group. The pyridoxine group received 0.2 g of vitamin B 6 before anesthesia induction, and the control group received normal saline intravenously. Both groups received a similar regimen of combined intravenous and inhalation general anesthesia. All patients received dexamethasone (intravenous) after anesthesia induction and ondansetron (intravenous) before surgery completion. Postoperative nausea and vomiting occurrence was recorded according to the patients' self-reported data. Other clinical data were collected from hospital system, and concentrations of blood interleukin-6 and substance P were measured by enzyme-linked immunosorbent assay.

Results: A total of 442 patients were screened, and 240 patients were equally randomized to the pyridoxine or control group. The incidence of postoperative nausea and vomiting was statistically significant lower in the pyridoxine group than in the control group (16.7% [20 of 120] vs . 35.8% [43 of 120]; relative risk = 0.47 [95% CI, 0.29 to 0.74]; absolute risk reduction = 0.20 [95% CI, 0.08 to 0.30]; P = 0.001), and pyridoxine decreased the incidence of postoperative nausea (12.5% [15 of 120] vs . 35% [42 of 120]; relative risk = 0.36 [95% CI, 0.21 to 0.61]; absolute risk reduction = 0.23 [95% CI, 0.12 to 0.33]; P < 0.001). There were no statistical differences in postoperative vomiting, time to the first postoperative nausea and vomiting occurrence, pain, serum interleukin-6 and substance P, and leukocyte and neutrophil counts.

Conclusions: In this single-center randomized trial, pyridoxine plus dexamethasone and ondansetron reduced the incidence of postoperative nausea and vomiting in patients undergoing elective gynecologic laparoscopic surgery under general anesthesia. These findings need to be validated in multicenter studies in diverse populations to ensure generalizability.

Fig. 1.

Flow chart of the trial. CONSORT, Consolidated Standards of Reporting Trials. ITT, intention-to-treat.

Fig. 2.

Incidence of postoperative nausea and vomiting (A), postoperative nausea (B), and postoperative vomiting (C).

Fig. 3.

Preoperative and postoperative plasma concentrations of substance P (n = 15; A and B) and interleukin (IL)-6 (n = 15; C and D). A and C, blood samples were collected before induction and immediately after surgery. B and D, blood samples were collected before induction and at 24 h after surgery.