Chewing gum prophylaxis for postoperative nausea and vomiting in the intensive care unit: a pilot randomised controlled trial

Objective: To test the effectiveness of chewing gum in the prophylaxis of postoperative nausea and vomiting (PONV) in patients admitted to the intensive care unit (ICU) after surgery. Design: Prospective, open label, pilot randomised controlled trial. Setting: Two metropolitan ICUs. Participants: Ninety postoperative adult patients admitted to the ICU. Intervention: Patients administered chewing gum, who chewed for at least 15 minutes every 4 hours, were compared with a control group, who were administered a 20 mL sip of water orally every 4 hours. Main outcome measures: The primary outcome was the number of patient-reported episodes of nausea in the first 24 hours after the operation. Secondary outcomes included vomiting or dry retching episodes, and duration and severity of nausea. Results: Forty-six patients were randomly allocated to chewing gum and 44 patients to water. There was no difference between groups in the number of patients with nausea (10 [22%] chewing gum v12 [27%] control patients; P = 0.72), nausea episodes (22 episodes; [median, 0; IQR, 0-0] v 21 episodes [median, 0; IQR, 0-1] per patient in each group respectively), vomiting/retching (2 [4%] chewing gum v 6 [14%] control patients; P = 0.24), or duration/ severity of nausea. Conclusion: Regular postoperative administration of chewing gum in a surgical ICU patient cohort did not reduce nausea, vomiting or retching. The prevalence of PONV is less than previously reported. Our findings can inform future studies of PONV prophylaxis in post-surgical ICU patients.