Evaluation of the Analgesic Efficacy of Preemptive Dipyrone in the Postoperative Period of Adenotonsillectomy in Children: A Randomized Clinical Trial

INTRODUCTION: Dipyrone is one of the most commonly used postoperative analgesics. However, there are only two randomized, placebo-controlled clinical trials evaluating its effect in pediatric tonsillectomies. OBJECTIVE: To compare postoperative pain outcomes following the use of pre-incisional dipyrone or placebo in pediatric adenotonsillectomy. METHODS: This was a randomized, double-blind, parallel, placebo-controlled clinical trial in children aged 4 to 14 years who underwent adenotonsillectomy. A total of 76 participants were randomized into the intervention/dipyrone group (n = 39) and the placebo group (n = 37). All received either dipyrone or saline solution (placebo) at one of two time points: before the surgical incision or at the end of surgery. RESULTS: The mean age was 6.8 years and weight was 32.1 kg. In the intervention group, vital signs were normal and only 7.7% experienced emesis, compared with 8.1% in the placebo group. Food intake was anticipated by 1,1 hours in the dipyrone group. Pain was controlled in at least 77.6% of participants at all evaluated time points (H0, H1, H3, and H6) in both groups. At H3, pain was controlled in 54.2% of the intervention group compared with 45.8% in the placebo group. In addition, the dipyrone group demonstrated a tendency toward a lower need for opioids in H1 and H3, reducing opioid administration by 50% and 52.63%, respectively, compared with placebo. CONCLUSION: A trend toward pain relief, earlier diet acceptance, and a lower need for opioids was observed in the group that received preemptive dipyrone. The results did not reach statistical significance, likely due to a type II error.