Risk of Severe Bleeding with Ibuprofen or Acetaminophen after Tonsillectomy

A recent study has found that ibuprofen may be linked to an increased risk of severe bleeding after pediatric tonsillectomies when compared to acetaminophen.

Investigators examined more than 1000 participants and found that they could not exclude a higher rate of severe bleeding in children receiving ibuprofen with the rate of severe bleeding in the ibuprofen group nearly doubling that in the acetaminophen group.

Investigators conducted a randomized, double-blind noninferiority trial across 4 different medic centers. In total, 1832 children were assessed for eligibility and 1091 were included in the trial. Of the 1091, 681 did not meet eligibility and 410 refused to participate. The 741 children that participated ranged in age from 2 years old to 18 and had undergone a tonsillectomy alone or tonsillectomy with adenoidectomy between May 3, 2012 and Jan. 20, 2017. Of the 741 children, 688 of them were included in a modified intention-to-treat analysis.

Investigators noted the rate and severity of bleeding were recorded using a postoperative bleeding severity scale. Type 1 was bleeding observed at home or evaluated in the emergency department without further intervention, type 2 was bleeds that required readmission for observation, and type 3 was bleeding that required a return to the operating room for control of hemorrhage.

Participants were randomized to receive a 10 mg dose of ibuprofen or 15 mg of acetaminophen every 6 hours for the first 9 postoperative days. Ibuprofen per volume per kilogram was matched to that of acetaminophen using a tasteless suspension to create equal volumes per dose of each treatment. The ibuprofen group consisted of 345 children and 343 were randomized into the acetaminophen group.

Of the 688 children included, 65 children experienced at least 1 event of post tonsillectomy bleeding (PBT). The ibuprofen group had 38 (11%) children experience PBT, while 27 (7.9%) children in the acetaminophen group experienced PBT.

Among the 38 children in the acetaminophen group who bled, 2 experienced 2 bleeding events. In the ibuprofen group, 4 children experienced 2 bleeding events, 1 child experienced 3 bleeding events, and 1 child experienced 4 bleeding events. In total, 15.8% of children in the ibuprofen group experienced multiple bleeding events.

Of the children who experienced bleeding in the acetaminophen group, 14 (51.9%) experienced type 1 bleeding, 9 (33.3%) experienced type 2, and 4 (14.8%) experienced type 3 bleeding. In the ibuprofen group, 16 (42.1%) experienced type 1, 12 (31.6%) experienced type 2, and 10 (26.3%) experienced type 3 bleeding.

The type 3 bleed rate in the acetaminophen group was 1.2% while the rate in the ibuprofen group was 2.9%.

Authors noted several limitations of their study. Conclusions are reliant on a carefully selected noninferiority margin. Lack of PTB literature that distinguishes between bleeding severity levels restricted noninferiorty analysis to type 3 bleeding. Loss to follow-up was high but equivalent between treatment groups. The modified intention-to-treat analysis did not distinguish between children who took the study medication as prescribed and those who took it less frequently or stopped use prematurely. It is not known if differences in timing, dose, or cumulative amount of ibuprofen affect bleeding risk.

Investigators concluded that the study could not support a conclusion that there is no difference in the severe bleeding risk when ibuprofen is used for postoperative analgesia compared with acetaminophen after a pediatric tonsillectomy. Investigators noted that Additional research is needed to determine whether ibuprofen results in increased bleeding when it is used for a shorter duration, less frequently, or as part of a multi-drug postoperative analgesic regimen.

This study, titled “Comparison of Ibuprofen vs Acetaminophen and Severe Bleeding Risk After Pediatric Tonsillectomy,” was published in the Journal of the American Medical Association.