Esketamine combined with hydromorphone versus hydromorphone for post-operative patient-controlled intravenous analgesia in children: a randomized controlled trial.

backgroundPostoperative pain and opioid-related adverse effects remain significant concerns in pediatric surgical patients. Esketamine, an NMDA receptor antagonist, may enhance analgesia and reduce opioid consumption at low doses. This study aimed to evaluate the effects of low-dose esketamine combined with hydromorphone for PCIA on postoperative pain control, bowel recovery, and safety in children undergoing abdominal surgery.

methodsThis randomized controlled clinical trial enrolled children aged from 3 to 12 years, who were scheduled to undergo abdominal surgery under general anesthesia and consented to the use of a PCIA pump. The study compared two groups. In the EH group (n = 49), esketamine (10 μg/kg/h) and hydromorphone (1 μg/kg/h), with bolus doses of hydromorphone 2 μg/kg and esketamine 20 μg/kg. In the H group (n = 49), analgesia was provided solely with hydromorphone (2 μg/kg/h), with bolus doses of 4 μg/kg. An identical lockout interval of 20 min was used. The primary outcome measured was the time-weighted average (TWA) pain score in the first 24 h postoperatively. Key secondary outcomes included the cumulative hydromorphone consumption within 48 h, the incidence of adverse events within 48 h, the time to first defecation, and the length of postoperative hospital stay.

resultsIn comparison to the H group, the EH group demonstrated a significantly lower movement TWA pain score in the first 24 h postoperatively (1.90 vs 3.67; mean difference (MD), 1.23; 95% confidence interval (CI) (0.50-1.94), P < 0.001). Additionally, the EH group showed a marked reduction in cumulative hydromorphone consumption within 48 h postoperatively (0.05 mg/kg vs 0.11 mg/kg; MD, 0.06 (95% CI 0.05-0.07); P < 0.001), a decreased requirement rate for glycerin enema (8.2% vs 32.7%; relative risk (RR), 0.73 (95% CI 0.59-0.91); P = 0.003), and a shorter length of postoperative hospital stay (8 days vs 10 days; MD, 1.00 (95% CI 0.00-3.00); P = 0.025).

conclusionsLow-dose esketamine combined with hydromorphone for PCIA significantly reduces the movement TWA pain score in the first 24 h post-surgery and decreases hydromorphone consumption within the first 48 h. Additionally, it reduces the need for glycerin enemas and shortens the length of hospital stay in children who have undergone abdominal surgery. The observed reduction in movement TWA pain score in the first 24 h and opioid consumption may facilitate improved continuous support for the early recovery of these children.

trial registrationThe trial was registered before patient enrollment at the Chinese Clinical Trial Registry (www. chictr.org.cn) (ChiCTR2200064762, date of registration: October 17, 2022).