Postoperative pain is the most notable issue after cesarean section (CS). Contributing factors include hyperalgesia, anxiety, depression, sleep disorders, and inflammation. This study explored the effects of esketamine on pain, hyperalgesia, depression, anxiety, sleep disorders, and inflammation after CS. This randomized, double-blind, controlled trial enrolled single-term pregnant women scheduled for elective CS. Participants were randomly included in the esketamine group (group E: intravenous esketamine 0.5 mg/kg + sufentanil 4 μg/kg followed by patient-controlled intravenous analgesia [PCIA] with esketamine 0.5 mg/kg) or the control group (C: normal saline + sufentanil 4 μg/kg PCIA). The primary outcome was the maximum pain numerical rating scale (NRS) score within 24 h postoperatively. Secondary outcomes included pain NRS scores for moving incision, visceral, and rest incision pain at 0–6 h, 6–12 h and 12–24 h; pressure pain threshold and tolerance at 30 min and 24 h postoperatively; PCIA drug consumption and number of compressions; time to first PCIA compression; serum C-reactive protein (CRP) at 24 h; incidence of drug-related side effects; and rates of anxiety, depression, and sleep disorders on postoperative day 2. Ninety-eight women were randomly included in group E (n=50) or C (n=48). Group E had significantly lower maximum NRS pain scores within 24 h (5 [4–5] vs. 6 [5–6], P=0.000) and relieved rest incision, visceral, and moving incision pain at all time points. The PCIA compression was significantly delayed, and CRP levels, as well as the incidence of postoperative depression, anxiety, and sleep disorders, were lower in group E. There were no statistically significant differences in hyperalgesia or side effects. Intravenous esketamine effectively reduces postoperative pain, psychological disorders, and inflammation after CS.

This study was registered in the Chinese Clinical Trial Registry with registration number ChiCTR2300078310.

The authors have declared no competing interest.

ChiCTR2300078310

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This randomized, double blind, placebo-controlled trial was approved by the Chongqing University Fuling Hospital ethics committee (2023CDFSFLYYEC-064).

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