Preemptive diclofenac reduces morphine use after remifentanil-based anaesthesia for tonsillectomy

Background: We investigated the effect of preincisional rectal diclofenac on pain scores and postoperative morphine requirements of children undergoing tonsillectomy after remifentanil-propofol anaesthesia in a randomized clinical trial. Methods: Induction and maintenance of anaesthesia were with remifentanil and propofol. Forty children were randomly assigned into two groups before incision. The diclofenac group (n = 20) received diclofenac suppositories (approximately 1 mg.kg(-1)) and the control group (n = 20) received no treatment. Following discontinuation of remifentanil, patient-controlled analgesia (PCA) with morphine (a loading dose 50 mug.kg(-1) , a background infusion 4 mug.kg(-1) .h(-1) and a demand dose 20 mug.kg(-1) with 5-min intervals) was started. We assessed pain score [verbal analogue scales (VAS), 0-10] and sedation level at 5-min intervals and recorded the total morphine consumption of the first hour in the PACU. Patients were discharged to the ward with a new PCA morphine programme (a demand dose 20 mug.kg(-1) with a lockout time of 30 min, for 4 h), and total morphine consumption was recorded. Results: The mean VAS score of the diclofenac group was significantly lower than the control group on arrival in the PACU (2.85 +/- 0.77, 7.60 +/- 0.83, respectively, P < 0.01) and it remained significantly lower in the PACU stay of the children. The mean total morphine consumption of the diclofenac group was less than the control group in the PACU (130.33 +/- 11.26 and 169.92 +/- 9.22, respectively, P = 0.012) and the ward (50.80 +/- 11.38 and 87.77 +/- 10.55, respectively, P = 0.021). Conclusions: Preemptive diclofenac given rectally reduced pain intensity and morphine requirements of children anaesthetized with remifentanil for tonsillectomy.