[Tonsillotomy and adenotonsillectomy in childhood. Study on postoperative pain therapy].

Background: The primary aim of this study was to determine whether the combination of i.v. ketoprofen and i.v. paracetamol provides superior postoperative analgesia in children undergoing adenoidectomy or tonsillotomy compared to either drug alone. The secondary goal was to assess the time until rescue analgesia was needed, propofol requirements and the incidence of vomiting and time of discharge from the postanaesthesia recovery unit (PARU).

Methods: This double-blinded study included 120 children (aged 3-13 years) scheduled for elective tonsillectomy, adenoidectomy or adenotonsillectomy. The children were randomly assigned to one of 3 groups of 40 children each, using the sealed envelope method. The children received i.v. ketoprofen 2 mg/kgBW (group 1) or paracetamol 15 mg/kgBW (group 2) or the combination of these 2 drugs (group 3) after induction of anaesthesia. Standardized general anaesthesia consisted of sevoflurane and fentanyl at a dose of 2-3 μg/kgBW. Pain was assessed using a 5-point scoring system based on the Smiley scale. The Smiley scale shows various faces from a laughing face which corresponds to the state of no pain to a very unhappy face which corresponds to the situation of worst pain (1: no pain, 2: mild pain, 3: moderate pain, 4: severe pain, 5: worst pain). Pain was assessed at 30 min, 1 h, 2 h, 3 h and 4 h after arriving in the PACU. If the pain score exceeded 2 an i.v. dose of 0.1 mg/kgBW morphine was administered as rescue analgesia.

Results: During the stay in the PACU the children in the combination group required significantly less supplementary rescue analgesia than children in the ketoprofen and paracetamol groups (17.5% versus 30.8% versus 45%, respectively, χ(2) analysis <0.05). Pain scoring was highest after paracetamol, however, this difference was only significant when compared to the group receiving the combination of paracetamol and ketoprofen (U-test p<0.05). Rescue analgesia was administered earliest in group 2 (paracetamol) reaching statistical significance, however, only when compared to group 3 (logrank test p<0.05). Propofol requirements and time to discharge from the PACU did not differ significantly between the 3 groups (χ(2) analysis; U-test; p>0.05). The overall incidence of vomiting was very low in this study with 6.4% (9/139). Significantly more children in the paracetamol group compared to ketoprofen group and combination group suffered from vomiting (17.5% versus 2.6% versus 2.5%; χ(2) analysis; p<0.05). The time to discharge from PACU did not differ significantly between the 3 groups (U-test: p>0.05).

Conclusion: The combination of i.v. paracetamol and i.v. ketoprofen provides superior postoperative analgesia compared to the single use of paracetamol.