Importance: Ibuprofen is an effective analgesic after tonsillectomy alone or tonsillectomy with adenoidectomy, but concerns remain about whether it increases postoperative hemorrhage.
Objective: To investigate the effect of ibuprofen compared with acetaminophen on posttonsillectomy bleeding (PTB) requiring surgical intervention in children.
Design, setting, and participants: A multicenter, randomized, double-blind noninferiority trial was conducted at 4 tertiary medical centers (Massachusetts Eye and Ear Infirmary, Boston; Naval Medical Center, San Diego, California; Naval Medical Center, Portsmouth, Virginia; Madigan Army Medical Center, Tacoma, Washington). A total of 1832 children were assessed for eligibility (presence of sleep-disordered breathing or obstructive sleep apnea, adenotonsillar hypertrophy, or infectious tonsillitis undergoing extracapsular tonsillectomy by electrocautery). Of these, 1091 were excluded because they did not meet eligibility criteria (n = 681) or refused to participate (n = 410); thus, 741 children aged 2 to 18 years undergoing tonsillectomy alone or tonsillectomy with adenoidectomy were enrolled between May 3, 2012, and January 20, 2017.
Interventions: Participants were randomized to receive ibuprofen, 10 mg/kg (n = 372), or acetaminophen, 15 mg/kg (n = 369), every 6 hours for the first 9 postoperative days.
Main outcomes and measures: Rate and severity of posttonsillectomy bleeding were recorded using a postoperative bleeding severity scale: type 1 (bleeds that were observed at home or evaluated in the emergency department without further intervention), type 2 (bleeds that required readmission for observation), and type 3 (bleeds that required a return to the operating room for control of hemorrhage). Type 3 bleeding was the main outcome measure. The noninferiority margin was set at 3%, and modified intention-to-treat analysis was used.
Results: Of the 741 children enrolled, 688 children (92.8%) (median [interquartile range] age, 5  years; 366 boys [53.2%]) received the study medication and were included in a modified intention-to-treat analysis. The rate of bleeding requiring operative intervention was 1.2% in the acetaminophen group and 2.9% in the ibuprofen group (difference, 1.7%; 97.5% CI upper limit, 3.8%; P = .12 for noninferiority). There were no significant adverse events or deaths.
Conclusions and relevance: This study could not exclude a higher rate of severe bleeding in children receiving ibuprofen after tonsillectomy alone or tonsillectomy with adenoidectomy. This finding should be considered when selecting a postoperative analgesic regimen. Further studies are needed to understand if bleeding risk is affected when ibuprofen is used for a shorter duration or in combination with acetaminophen for postoperative analgesia.
Trial registration: ClinicalTrials.gov identifier: NCT01605903.