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

Study Summary

100 predominantly male patients undergoing postoperative rehabilitation following ankle fracture surgery who experienced rehabilitation-related pain were included in this dual-arm, single-centre, double-blind controlled trial in which patients were randomized to either receive 65% premixed nitrous oxide or 100% oxygen. The primary outcome of interest was pain intensity measured using the Visual Analogue Scale (VAS). Secondary outcomes included Numeric rating scale (NRS) for anxiety, physiological parameters (heart rate, blood pressure and oxygen saturation), incidences of adverse effects, patient satisfaction, therapist satisfaction, treatment acceptance, and residual pain following rehabilitation. Outcomes were assessed at baseline, 5 minutes after the start of treatment, 10 minutes after the start of treatment, 5 minutes after completion of rehabilitation, and residual pain was assessed the following morning. Overall, the results of the study revealed that nitrous oxide significantly reduced pain during rehabilitation compared with oxygen, while also improving patient and therapist satisfaction, treatment acceptance, and reducing residual pain, with only mild transient adverse effects. These findings suggest that premixed nitrous oxide is a safe and effective analgesic option for managing pain during postoperative ankle fracture rehabilitation.