# Effect of S-ketamine on postoperative pain sensitivity in children with preoperative chemotherapy

## TL;DR

This study shows that S-ketamine reduces postoperative pain in children who received chemotherapy before surgery.

## Contribution

The study is the first to evaluate S-ketamine's effect on chemotherapy-induced postoperative pain in children.

## Key findings

- S-ketamine increased postoperative mechanical pain thresholds at 24 and 48 hours.
- S-ketamine reduced postoperative pain scores on FLACC and WBS scales.
- The infusion time of S-ketamine correlated with improved pain outcomes.

## Abstract

Children undergoing chemotherapy experience exacerbated postoperative pain and prolonged pain perception. Intraoperative intravenous administration of S-ketamine can alleviate postoperative pain. However, its efficacy in mitigating chemotherapy-induced hyperalgesia remains uncertain. This study evaluates the effect of S-ketamine on postoperative pain sensitivity in children who received preoperative chemotherapy.

A total of 40 children undergoing preoperative chemotherapy and scheduled for open abdominal surgery were recruited from our center and randomly assigned to either the S-ketamine group or the control group. The primary outcomes included postoperative mechanical pain threshold, FLACC scale, Wong-Baker FACES pain rating scale (WBS), and cases of additional analgesic use. Secondary outcomes included intraoperative hemodynamic changes, extubation time, and incidence of adverse events.

Thirty-six children were included in the study. The two groups had no significant difference in preoperative mechanical pain thresholds (P = 0.585). Patients receiving S-ketamine had higher mechanical pain thresholds at 24 and 48 h post-surgery (both P < 0.001). Preoperative FLACC and WBS were 0 in both groups. Postoperative FLACC and WBS showed significant differences at various time points (all P < 0.05). There is a negative correlation between infusion time of S-ketamine and postoperative mechanical pain threshold at 24 h (r = −0.570, P = 0.014) and 48 h postoperatively (r = −0.643, P = 0.004) in the S-ketmanie group.

Intravenous S-ketamine significantly increases postoperative mechanical pain threshold and reduces pain in patients who received neoadjuvant chemotherapy.

Children undergoing chemotherapy experience exacerbated postoperative pain and prolonged pain perception. Intraoperative intravenous administration of S-ketamine can alleviate postoperative pain. However, its efficacy in mitigating chemotherapy-induced hyperalgesia remains uncertain. This study fills the gap in this area.This study evaluates the effect of S-ketamine on postoperative pain sensitivity in children who received preoperative chemotherapy.S-ketamine’s NMDAR antagonism may partly reduce pain sensitivity, thus reversing the pain effect.The results of this study provide promising evidence for the potential benefits of S-ketamine in improving postoperative pain outcomes in this patient population.The infusion time of S-ketamine ranged from 30 to 655 min, suggesting that the beneficial effect can be achieved within this time frame.

Children undergoing chemotherapy experience exacerbated postoperative pain and prolonged pain perception. Intraoperative intravenous administration of S-ketamine can alleviate postoperative pain. However, its efficacy in mitigating chemotherapy-induced hyperalgesia remains uncertain. This study fills the gap in this area.

This study evaluates the effect of S-ketamine on postoperative pain sensitivity in children who received preoperative chemotherapy.

S-ketamine’s NMDAR antagonism may partly reduce pain sensitivity, thus reversing the pain effect.

The results of this study provide promising evidence for the potential benefits of S-ketamine in improving postoperative pain outcomes in this patient population.

The infusion time of S-ketamine ranged from 30 to 655 min, suggesting that the beneficial effect can be achieved within this time frame.