Intravenous lidocaine versus dexamethasone to prevent postoperative vomiting in children tonsillectomy: a prospective randomized controlled trial.

Introduction: we evaluate the effectiveness of lidocaine infusion compared to the intravenous dexamethasone and placebo on postoperative vomiting and first oral intake in children post tonsillectomy.

Methods: we conducted a prospective double-blinded randomized and controlled clinical trial involving children aged between 3 and 13 years proposed for elective tonsillectomy without or with adenoidectomy under general anesthesia. They were randomized into 3 groups: lidocaine group included patients who received intravenous bolus of 2 mg/kg lidocaine over 5 minutes after the induction of anesthesia. Then, they received an infusion of 1.5 mg/kg/h until the end of the surgical procedure, dexamethasone group included patients who received intravenous dexamethasone 0.15 mg/kg administrated over 5 minutes after the induction of anesthesia followed by an identical rate of 0.9% saline and the saline group included patients who received an equivalent volume of 0.9% saline. For data analysis, we tested the normality of variables using the Shapiro-Wilk test. We used analysis of variance (ANOVA) or the Kruskal-Wallis test for between-group comparisons, as appropriate. The X test and Fisher´s exact test were used for inferences on proportions. A two-sided P-value was considered significant when p≤0.05. All analyses were performed with IBM SPSS≤ 25.0.0 for windows.

Results: eighty-three (83) children were analyzed in our study and randomized into 3 groups: 27 children for each lidocaine and dexamethasone group and 29 children for the Saline group. The demographic data were not significantly different between the three groups such as age (p=0.246), gender (p=0.378), and body mass index (BMI) with p=0.233. The duration of surgery and anesthesia was also comparable in the 3 groups (p=0.893). Patients of the lidocaine and dexamethasone group had at least one episode of retching, vomiting, or both less than the saline group in the post-anesthetic care unit with p respectively 0.015 and 0,035, and in the ward with p respectively 0.004 and 0,038 Without a significant difference between the dexamethasone and the lidocaine group. The time to the first oral intake was significantly shorter in the dexamethasone group and the lidocaine group compared with the saline group (p=0.0001) with no statistical difference between the dexamethasone and lidocaine groups.

Conclusion: lidocaine infusion is as effective as intravenous dexamethasone on postoperative vomiting as well as on oral intake in children post tonsillectomy.