Analgesic efficacy of rectal acetaminophen and ibuprofen alone or in combination for paediatric day-case adenoidectomy^†

Background

Acetaminophen and non-steroidal anti-inflammatory drugs have different mechanisms of action. We investigated if combining rectal acetaminophen with ibuprofen would provide better postoperative analgesia compared with either drug alone after adenoidectomy in children.

Methods

160 children, aged 1–6 yr, undergoing day-case adenoidectomy, were randomized to receive either acetaminophen 40 mg kg⁻¹, ibuprofen 15 mg kg⁻¹, their combination, or placebo rectally immediately after anaesthetic induction. A standard anaesthetic method was used and all children received alfentanil 10 μg kg⁻¹ i.v. during induction. Meperidine 5–10 mg i.v. was used for rescue analgesia for a pain score (Objective Pain Scale) over 3. Recovery times, sedation scores and the need for rescue analgesia and adverse events during the first 24 h after anaesthesia were recorded. Rescue analgesic at home was ibuprofen 10 mg kg⁻¹.

Results

Total meperidine requirements were significantly less in the groups receiving acetaminophen, ibuprofen, or their combination compared with the group receiving placebo indicating an opioid-sparing effect of 19–28% (P<0.05). Children given acetaminophen were more sedated than those given ibuprofen (P<0.05). Discharge criteria were fulfilled earlier in the ibuprofen group than in all the other groups (P<0.05). At home, less children (49%) needed rescue analgesia in the combination group compared with the other groups (74–77%) (P<0.02).

Conclusions

We conclude that prophylactically administered rectal acetaminophen combined with ibuprofen does not improve analgesia after adenoidectomy in the immediate postoperative period compared with either drug alone but does decrease the need for analgesia at home. Ibuprofen results in lesser sedation and faster discharge than when acetaminophen is used.