Pre-mixed nitrous oxide/oxygen mixture treatment of pain induced by postoperative dressing change for perianal abscess: Study protocol for a randomized, controlled trial.

Aim: This study aims to evaluate the safety and analgesic efficacy of pre-mixed nitrous oxide/oxygen mixture treatment of pain induced by dressing change for perianal abscess.
Design: This protocol is a randomized, double-blind, placebo-controlled trial.
Methods: This study will be implemented in the Hospital of Traditional Chinese Medicine. Subjects enrolled in this study are hospitalized patients who suffered from moderate to severe pain due to dressing change after incision and drainage. Two hundred patients will be selected and randomly assigned to either an intervention or a control group. The intervention group will get routine pain treatment plus pre-mixed nitrous oxide/oxygen mixture treatment and the control group will be treated with routine pain management plus medical air treatment. All these patients, medical staff and investigators are blind to the nature of the gas in each cylinder, which is randomized. Data will be collected at baseline (T0), 5 min (T1) after the starting of intervention and 5 min post intervention (T2) for each group. The primary outcome is the level of pain relief at T1 and T2. The secondary outcomes cover physiological parameters, adverse events, satisfaction of patients and health professionals and the acceptance from patients.
Discussion: Results of this study will be discussed and the safety and effect of nitrous oxide/oxygen treatment of pain induced by dressing change will be proven.
Impact: When the finding of this study has an active effect on the treatment of pain caused by dressing change, it may provide more options for nursing staff to choose nurse-led analgesia techniques and then improving the level and quality of pain care as well as patients' overall satisfaction with the Anorectal Department in China.
(© 2020 John Wiley & Sons Ltd.)