Hydromorphone Versus Fentanyl-Based Induction of Anesthesia for Postoperative Pain and Emergence Delirium in Children Undergoing Strabismus Surgery: A Randomized, Double-Blind Comparative Study.

Purpose: This study aimed to investigate the effects of hydromorphone and fentanyl-based induction of anesthesia for immediate postoperative analgesia in pediatric patients.

Patients and methods: This was a prospective, double-blind, randomized controlled trial. 186 preschool children aged 3 to 7 years old scheduled for strabismus surgery were randomized to receive hydromorphone 0.02 mg/kg (hydromorphone group; n = 80) or fentanyl 3 μg/kg (fentanyl group; n = 80). The primary outcome was the Face, Legs, Activity, Cry, and Consolability (FLACC) pain score at extubation. Secondary outcomes included the incidence of postoperative emergence delirium (ED), the proportion of subjects who received rescue analgesia, Ramsay sedation scores, heart rate, mean arterial pressure, and SpO₂ in post-anesthesia care unit, and perioperative adverse events.

Results: From November 10, 2020, to May 26, 2022,186 patients at West China Hospital were enrolled, 153 (37.5% male) of whom received administration of fentanyl (n = 76) or hydromorphone (n = 77). The hydromorphone group showed lower FLACC pain scores at the time of extubation (median [IQR], hydromorphone vs. fentanyl, 0 [0-0] vs. 0 [0-1], Mann-Whitney U = 2457.0, Z = -2.469, p = 0.014). The incidence of ED in the hydromorphone group was statistically lower than that in the fentanyl group (75.3% vs. 93.4%, p = 0.004, relative risk and 95% CI was 0.8 (0.7, 0.9)). Other secondary outcomes were comparable between the two groups.

Conclusion: Hydromorphone administration during induction may improve postoperative pain control and reduce the incidence of ED in PACU after pediatric strabismus surgery.

Trial registration: This study was registered at the Chinese Clinical Trials Register (www.chictr.org.cn) (number: ChiCTR2000039555, date of registration: 31/10/2020).