The Effects of Capsaicin Ointment Application to the K‑K9 Acupressure Point on Nausea and Vomiting During Cesarean Section Under Spinal Anesthesia

Background: Nausea and vomiting are among the most important and the most common intraoperative and postoperative complications. Objective: This study aimed to determine the effects of capsaicin ointment application to the K‑K9 acupressure point on intraoperative and postoperative nausea and vomiting associated with cesarean section (CS) under spinal anesthesia. Methods: This double‑blind three‑group randomized controlled trial was conducted on 120 women who referred to Ommolbanin Hospital, Mashhad, Iran, to undergo nonemergency CS under spinal anesthesia. Women were randomly allocated to three groups to receive capsaicin ointment on the K‑K9 point (intervention group), capsaicin ointment on the K‑D2 point (control group), and Vaseline ointment on the K‑K9 point (placebo group). Nausea, vomiting, and retching were assessed at five time points, namely during and 30, 60, 90, and 120 min after CS. Moreover, the need for antiemetic medications was also assessed in all three groups. The data were analyzed through running the one‑way analysis of variance, the Kruskal– Wallis, the Friedman, and the Chi‑square tests. Results: There were no significant differences among the groups, respecting the scores of nausea, vomiting, and retching at different measurement time points (P > 0.05). However, the number of women who needed antiemetic medication in the intervention group (11) was significantly less than the control (22) and the placebo (15) groups (P = 0.04). Conclusion: Capsaicin ointment application to the K‑K9 acupressure point is an easy‑to‑use noninvasive method for significantly reducing the need for antiemetic medications during and after CS under spinal anesthesia.