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.