Analgesic effect of premixed nitrous oxide in postoperative rehabilitation for ankle fractures: a randomized controlled trial.

INTRODUCTION

The global incidence of ankle fractures is on the rise, effective postoperative rehabilitation is a crucial aspect of surgical management. However, the occurrence of severe pain during the rehabilitation continues to pose a substantial clinical challenge.

METHODS

The study utilizes a dual-arm, single-center, double-blind, randomized controlled trial design. A total of 100 participants were enrolled. Participants included patients experiencing acute pain (self-reported pain score ≥4) who underwent postoperative rehabilitation for ankle fractures. Participants undergoing rehabilitation training were randomized to receive either 65% nitrous oxide or 100% oxygen. The primary outcome measured was the pain score, while secondary outcomes encompassed anxiety scores, physiological indices, side effects, patient and therapist satisfaction, acceptance, and residual pain.

RESULTS

Pain scores were found to be significantly lower in the nitrous oxide group than in the oxygen group (T1: median difference -3.0, [95% CI -3.4 to -2.6]; p < 0.001; T2: median difference -2.0, [95% CI -2.8 to -1.2]; p < 0.001). Compared with the oxygen group, both therapists (p < 0.001) and participants (p < 0.001) in the nitrous oxide group reported significantly higher satisfaction levels. Acceptance rate showed significant intergroup differences (p < 0.001). No severe adverse effects were observed in either group. Anxiety scores between the two groups did not show a significant difference (p = 0.31, η2 = 0.027).

CONCLUSION

The safety and analgesic profile of nitrous oxide renders it a suitable option for pain management in postoperative ankle fractures rehabilitation, thus providing a safe and easily manageable alternative to the current available strategies.

CLINICAL TRIAL REGISTRATION: We have registered at https://www.chictr.org.cn and the registration number is: ChiCTR2400089379.