A fixed inhaled nitrous oxide/oxygen mixture as an analgesic for adult cancer patients with breakthrough pain: study protocol for a randomized controlled trial

Abstract

BackgroundThe management of breakthrough pain in cancer patients is always a challenge for medical professions. Occurring in 80% of cancer patients with advanced disease, breakthrough pain significantly decreases both patient’s and caregiver’s quality of life. The aim of this study is to assess the analgesic efficacy of a fixed inhaled nitrous oxide/oxygen mixture for adult cancer patients with breakthrough pain.Methods/designThis is a randomized, placebo-controlled, double-blind study; it will be conducted in the General Hospital of Ningxia Medical University. The target study subjects are at least 18 years old, and are hospitalized cancer patients who are receiving routine opioids to control cancer-related pain but still experience breakthrough pain. A total of 240 patients will be recruited and randomly allocated between three treatment groups (A, B, C) and a control group (group D) in a ratio of 3:1. All treatment groups (A, B, C) will receive standard pain treatment (oral immediate-release morphine) plus a pre-prepared nitrous oxide/oxygen mixture, and the control group (D) will receive the standard pain treatment plus oxygen. Patients, doctors, nurses, and data collectors are all blind to the experiment. Assessments will be taken before treatment (T0), at 5 min (T1) and 15 min (T2) during treatment, and at 5 min after treatment (T3). The primary endpoint measures will be the percentage of patients whose pain is relieved at T1, T2, and T3. Secondary outcome measures will include the safety of treatment, adverse events, and satisfaction from both health professionals and patients.DiscussionThis study aims to provide an effective and practical intervention for a fast breakthrough pain relief and to improve cancer patients’ quality of life significantly. The Evidence-Based Medicine Working Group claim that a randomized, double-blind, placebo-controlled experimental intervention is the most appropriate design to demonstrate its efficacy, so this study could give a new approach to controlling breakthrough pain episodes.Trial registration ChiCTR-INC-16008075. Registered on 8 March 2016.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-016-1739-9) contains supplementary material, which is available to authorized users.

Premixed nitrous oxide/oxygen as an analgesic for dressing in patients with perianal abscess after surgery: study protocol for a randomized, within-patient, controlled trial

“…The determination of its sample size was on the basis of preliminary experimental data collected in the Anorectal Department for 30 patients. and our previous studies involved burn-dressing and cancer breakthrough pain [15,24]. The data indicated that 55% of participants receiving premixed nitrous oxide/oxygen had a meaningful change in pain score (a drop at least one-third of pain score [25]) at T1 and T2, while 15% of patients receiving oxygen was.…”

“…The expert will not be involved in the recruitment, gas distribution, date collection. Then, the random numbers will be stored and sealed in a designated research office to ensure concealment [15]. In order to maintain a double-blind environment, nurses and researchers are blinded and not allowed to touch the random numbers unless they can put forward justifiable reason and get the approval from the project supervisor.…”

“…The patients will receive an informed consent form and get an explanation from investigators regarding the aim, benefits and possible risks of the trial before the study is carried out. Eligible patients will be randomly allocated into two groups, inhaling premixed nitrous oxide/oxygen or oxygen with a one-way valve, specially designed oral-nasal mask [15]. The patients hold the self-administered mask that can be controlled by their own negative pressure to inhale gas until the dressing is over.…”

“…Its analgesic effects have been known for nearly two centuries. Studies [13][14][15] have confirmed the safety of premixednitrous oxide used pain management. In addition, the main advantage of this analgesic gas is that it can't cause loss of consciousness, and thus patients can control their own maintenance of gas flow [16].…”

Immersive virtual reality as analgesia for women during hysterosalpingography: study protocol for a randomized controlled trial

“…The worst pain severity as the primary end-point measure is employed to estimate sample size in the current research according to previous studies on physical therapy for pediatric burn injury pain and dentalgia pain [19,24]. According to our previous study on breakthrough pain [26], we used a pilot trial to determine the sample size. Fourteen subjects recruited in May 2019 were invited to the pilot trial.…”