Nitrous oxide 50% / Oxygen 50%

AIM: The Italian Society of Paediatric Dentistry (SIOI) is committed to encourage all dental practitioners to provide safe and updated prevention and treatment strategies for oral diseases in paediatric patients. SIOI promotes quality communication and information to parents and caregivers for prevention and awareness of oral diseases in the paediatric population. The purpose of this SIOI Policy is to provide dental professionals with comprehensive guidance on effective use of nitrous oxide/oxygen analgesia/anxiolysis for children, ensuring that treatment decisions are based on the latest and highestquality scientific evidence. METHODS: This Policy is based on a review of current highestquality literature, including systematic reviews, meta-analyses, recommendations, manuscripts and best practices published over the last 20 years. An extensive search was conducted using Pubmed® /MEDLINE, including the following parameters: nitrous oxide, oxygen, anxiolysis, relative analgesia, dental fear, anxiety, child. Papers for review were chosen from the list of articles and manuscripts which met the criteria and from references, within the selected articles and manuscripts. Recommendations were also based upon expert and consensus opinion by experienced researchers and clinicians.

Abstract licence: CC BY-NC

BACKGROUND: Patients with hematological malignancies received multiple hypodermic injections of recombinant human granulocyte colony-stimulating factor. Procedural pain is one of the most common iatrogenic causes of pain in patients with hematological malignancies. It is also identified as the most commonly occurring problem in clinical care in the Department of Hematology and Oncology at Shenzhen University General Hospital. However, providing immediate relief from pain induced by hypodermic injection of recombinant human granulocyte colony-stimulating factor remains a major challenge. This trial aims to evaluate the safety and analgesic efficacy of a fixed nitrous oxide/oxygen mixture for patients with hematological malignancies and experiencing procedural pain caused by hypodermic injection of recombinant human granulocyte colony-stimulating factor in the department. METHODS: The nitrous oxide/oxygen study is a single-center, randomized, double-blind, placebo-controlled trial involving patients with hematological malignancies who require hypodermic injections of recombinant human granulocyte colony-stimulating factor for treatment. This trial was conducted in the Hematology and Oncology Department of Shenzhen University General Hospital. A total of 54 eligible patients were randomly allocated to either the fixed nitrous oxide/oxygen mixture group (n = 36) or the oxygen group (n = 18). Neither the investigators nor the patients known about the randomization list and the nature of the gas mixture in each cylinder. Outcomes were monitored at the baseline (T0), immediately after hypodermic injection of recombinant human granulocyte colony-stimulating factor (T1), and 5 min after hypodermic injection of recombinant human granulocyte colony-stimulating factor (T2) for each group. The primary outcome measure was the score in the numerical rating scale corresponding to the highest level of pain experienced during hypodermic injection of recombinant human granulocyte colony-stimulating factor. Secondary outcomes included the fear of pain, anxiety score, four physiological parameters, adverse effects, total time of gas administration, satisfaction from both patients and nurses, and the acceptance of the patients. DISCUSSION: This study focused on the safety and analgesic efficacy during hypodermic injection of recombinant human granulocyte colony-stimulating factor procedure. Data on the feasibility and safety of nitrous oxide/oxygen therapy was provided if proven beneficial to patients with hematological malignancies during hypodermic injection of recombinant human granulocyte colony-stimulating factor and widely administered to patients with procedural pain in the department. TRIAL REGISTRATION: Chinese Clinical Trial Register, ChiCTR2200061507. Registered on June 27, 2022. http://www.chictr.org.cn/edit.aspx?pid=170573&htm=4.

Abstract licence: CC BY

Vacuum assisted closure (VAC) is commonly used in clinical practice to promote wound healing. During the dressing removal of VAC, patients may suffer from different degrees of pain, or even discontinue treatment due to severe pain. Our study sought to determine whether or not nitrous oxide analgesia decreases pain compared to oxygen placebo during removal of VAC dressing. This study is a double-blind, placebo-controlled randomized trial targeting patients who underwent replacement of VAC dressings in orthopedics. All patients were randomized in a 1:1 ratio to receive 65% premixed nitrous oxide/oxygen versus 100% oxygen. The primary outcome was the intensity of pain during the intervention. Secondary outcomes included adverse effects, satisfaction of patients, and physiological parameters (blood pressure, heart rate, oxygen saturation). Between 18 February, 2022 and 9 May, 2023, 114 participants were enrolled, 57 patients were allocated to the intervention group (premixed nitrous oxide/oxygen), 57 patients were enrolled in the control group (oxygen). The baseline and procedural characteristics were comparable between the two groups. The pain score reported by patients immediately after removing the dressing in the intervention group was significantly lower than that in the control group (median 3.0 vs. 6.3, P < 0.001). The satisfaction of patients in the intervention group significantly increased (Z=-6.861, P < 0.001). There were no significant differences in vital signs, operation duration, and adverse reactions between the two groups. Premixed nitrous oxide/oxygen can reduce the pain caused by removal VAC dressing in patients and can be considered an effective analgesic measure.

Abstract licence: CC BY-NC-ND

BACKGROUND: Vacuum assisted closure (VAC) is an effective treatment that promotes wound healing in clinical practice. However, the pain caused by Vacuum assisted closure VAC dressing removal is still a challenge for patients and medical staff. The purpose of this study was to investigate the analgesic effect and safety of premixed nitrous oxide/oxygen in the treatment of pain caused by VAC dressing removal. METHODS/DESIGN: This study is a single center, randomized, placebo-controlled, double-blind clinical trial. A total of 100 patients requiring VAC dressing removal were recruited and randomly divided into an intervention group and a control group. The intervention group will receive routine treatment plus a premixed nitrous oxide/oxygen mixture, and the control group will receive routine treatment plus oxygen. Participants and researchers are all blind to the operation process. The results of each group will be monitored at baseline (T0), 5 min after intervention (T1), and 5 min after finishing intervention (T2), 15 min after finishing intervention (T3). The primary outcome measure was pain intensity. Secondary outcomes included physiological parameters, adverse reactions, operators, and patients' satisfaction. DISCUSSION: This study will explore the analgesic effect of oxide/oxygen mixture on VAC dressing removal. If it is beneficial to patients with VAC dressing change, it will be helpful for pain management of VAC dressing removal. TRIAL REGISTRATION: Chinese Clinical Trial Register ChiCTR2200056742. Registered on February 13, 2022.

Abstract licence: CC BY-NC-ND

BACKGROUND: With the increasing incidence of femoral neck fracture and necrosis of the femoral head, total hip arthroplasty is the ideal treatment due to its advantages of small damage and quick recovery. Pain is a decisive factor in determining the early and active participation of patients in rehabilitation after total hip arthroplasty. Nitrous oxide with its rapid analgesic effect is often used to reduce pain in minor procedures. The purpose of this study was to determine if nitrous oxide reduces pain during rehabilitation after total hip arthroplasty. METHODS: This is a randomized, double-blind, controlled clinical study. Patients ≥ 65 years old undergoing rehabilitation training after total hip arthroplasty with acute pain (VAS ≥ 4) are included. Participants will be randomly assigned to nitrous oxide or placebo control group using randomization before rehabilitation training in a ratio of 1:1. Rehabilitation will be carried out by therapists. The two gases will be implemented by trained and qualified nurses. A total of 160 participants (80 per group) will be enrolled, accounting for an estimated 20% dropout rate. The primary endpoint is the between-group difference in pain intensity measured by Visual Analogue Scale (VAS) at T1 (during rehabilitation), with additional assessments at T0 (baseline) and T2 (post-rehabilitation). Longitudinal analyses using generalized estimating equations (GEE) will include T0, T1, and T2. Key secondary outcomes include anxiety score (VAS), Berg balance scale (BBS), functional ambulation category (FAC), side effects, satisfaction, and acceptance. Safety monitoring includes continuous assessment of oxygen saturation, vital signs, and predefined stopping criteria for adverse events. CONCLUSION: This study is designed to generate evidence regarding the effectiveness and safety of nitrous oxide for analgesia in patients undergoing rehabilitation after total hip arthroplasty. This intervention has the potential to provide more effective support options for pain management in rehabilitation training for elderly patients, potentially improving patient satisfaction and quality of life. If proven effective, this intervention may provide preliminary evidence for a new analgesic option in hospital and rehabilitation settings. TRIAL REGISTRATION: This trial was registered at the Chinese Clinical Trial Registry (ChiCTR), on August 6, 2024 (registration number ChiCTR2400087866).

Abstract licence: CC BY-NC-ND

Nitrous oxide has been used worldwide for labor analgesia for over a century. It offers a non-invasive, rapidly acting, and self-administered option for pain and anxiety management. The present investigation examines efficacy, safety, and limitations of nitrous oxide when compared to other labor analgesic modalities, including epidural anesthesia, intravenous opioids, and non-pharmacologic methods. Pharmacologically, nitrous oxide has both analgesic and anxiolytic effects via NMDA receptor inhibition, opioid receptor activation, and GABA-A modulation. While it can be less effective than epidurals in producing complete analgesia, studies demonstrate moderate pain relief, high maternal satisfaction, and preserved mobility. Safety considerations include common, mild adverse effects such as nausea, dizziness, and vomiting, with rare risks of hypoxia, especially when combined with other sedatives or in vitamin B12-deficient patients. Fetal exposure occurs via placental transfer, but it is rapidly cleared, with no consistent evidence of significant neonatal harm. In this regard, data on long-term neurodevelopmental outcomes is limited. Comparative studies suggest that nitrous oxide's efficacy is like certain opioids but inferior to epidural analgesia, and it offers both patient autonomy and ease of administration. Barriers that prevent broader adoption of nitrous include limited availability in rural settings, equipment costs, and the need for proper scavenging systems. Future research should focus on optimizing delivery systems, exploring long-term neonatal safety, and defining nitrous oxides's role in multimodal pain management. In summary, nitrous oxide represents a safe, flexible, and patient-centered analgesic option for labor, particularly for individuals who are looking for mobility, self-control, and a less invasive alternative to neuraxial anesthesia.

Abstract licence: CC BY-NC