The use of inhaled nitrous oxide for analgesia in adult ED patients: a pilot study

Analgesic effect of nitrous oxide during manual therapy after anterior cruciate ligament reconstruction: a study protocol for a randomized controlled trial

BACKGROUND

Many patients during manual therapy after anterior ligament reconstruction will experience severe pain, which has a negative impact on their rehabilitation. However, there is rarely an analgesic method for these patients during rehabilitation. Nitrous oxide with rapid analgesic and sedative effects is often used to relieve pain in minor procedures. The purpose of this study is to determine whether or not nitrous oxide analgesia decreases pain compared to oxygen during manual therapy after anterior ligament reconstruction.

METHODS/DESIGN

This single-center, randomized, double-blind and controlled trial will recruit 120 patients. Patients ≥ 18 years old undergoing manual therapy after anterior ligament reconstruction (1 month post-operative) with acute pain (VAS ≥ 4) are included. The main exclusion criteria included the following: pulmonary embolism, intestinal obstruction, pneumothorax. Patients will be randomly allocated to the intervention group (A) and the control group (B) in a ratio of 1:1. Doctors, therapists, patients, and data collectors are all blind to the study. The manual therapy will be performed by therapists. Nurses who implemented the intervention handed the doctors envelopes containing the patients' codes and allocation of A or B. Group A will receive a pre-prepared nitrous oxide/oxygen mixture plus conventional treatment (no analgesic) given as 30-min treatment sessions, once daily, and group B will receive oxygen plus conventional treatment (no analgesic) under the same conditions. Assessments will be taken 2 min before the intervention (T0), 5 min after the beginning of the intervention (T1), and 5 min after the intervention finished (T2). The primary outcome is pain score. Secondary outcomes include vital signs, side effects, joint range of motion, adjuvant analgesia need, therapist and patient satisfaction, and whether willing to receive the same gas again.

EXPECTED OUTCOMES

We expect nitrous oxide inhalation to have a beneficial effect on the pain of patients who receive manual therapy after anterior ligament reconstruction.

DISCUSSION

If this treatment appears beneficial, it could improve patients' satisfaction and quality of life potentially and even be implemented widely in hospital and rehabilitation settings.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, ChiCTR2200061175 (Version 2.0 June 15, 2022), https://www.chictr.org.cn .

Efficacy of nitrous oxide in adults undergoing puncture biopsy: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Nitrous oxide (N2O) with rapid analgesic effect is often used to relieve pain induced by diagnostic procedures. This review was conducted to evaluate the efficacy and safety of N2O in patients undergoing puncture biopsy.

METHODS

We systematically searched PubMed, Embase, the Cochrane Library, Web of Science, Scopus and the ClinicalTrials.gov up to March, 2022. Randomized controlled trials (RCTs) were included if they investigated the effect of N2O in adults undergoing puncture biopsy. The primary outcome was pain score. Secondary outcomes included anxiety score, patient satisfaction and side effects.

RESULTS

Twelve RCTs with 1070 patients were included in the qualitative review, of which eleven RCTs were included in the meta-analysis. Pooled analysis suggested that compared with the controls (placebo, lidocaine and midazolam), N2O had better analgesic effect (MD -1.12, 95% CI -2.12 to -0.13, P = 0.03; I2 = 94%). In addition, N2O significantly alleviated patient anxiety (MD = -1.79, 95% CI -2.41 to -1.18, P<0.00001; I2 = 0%) and improved patient satisfaction (MD 1.81, 95% CI 0.11 to 3.50, P = 0.04; I2 = 92%). There was no significant difference regrading the risk of nausea (RR 2.56; 95% CI 0.70 to 9.31, P = 0.15; I2 = 0%), headache (RR 0.62, 95% CI 0.17 to 2.33, P = 0.48; I2 = 46%), dizziness (RR 1.80, 95% CI 0.63 to 5.13, P = 0.27; I2 = 0%) or euphoria (RR 2.67, 95% CI 0.81 to 8.79, P = 0.11; I2 = 8%) between the N2O group and the control group.

CONCLUSION

The present review suggested that N2O might be effective for pain management in patients undergoing puncture biopsy.

Pain management in the emergency department: a clinical review

Pain is one of the most common reasons for patients to visit the emergency department. The ever-growing research on emergency department analgesia has challenged the current practices with respect to the optimal analgesic regimen for acute musculoskeletal pain, safe and judicious opioid prescribing, appropriate utilization of non-opioid therapeutics, and non-pharmacological treatment modalities. This clinical review is set to provide evidence-based answers to these challenging questions.

Success rate of nitrous oxide-oxygen procedural sedation in dental patients: systematic review and meta-analysis

The aim of this systematic review was to determine the success rate of nitrous oxide-oxygen procedural sedation (NOIS) in dentistry. A systematic digital search was conducted for publications or reports of randomized controlled trials evaluating the clinical performance of NOIS. Abstracts of research papers were screened for suitability, and full-text articles were obtained for those who met the inclusion and exclusion criteria accordingly. The quality of the studies was assessed using the revised Cochrane risk-of-bias tool (RoB 2). A total of 19 articles (eight randomized clinical trials with parallel intervention groups and 11 crossover trials), published between May 1988 and August 2019, were finally selected for this review. The studies followed 1293 patients reporting NOIS success rates, with a cumulative mean value of 94.9% (95% CI: 88.8–98.9%). Thirteen trials were conducted on pediatric populations (1098 patients), and the remaining six were conducted on adults (195 patients), with cumulative efficacy rates of 91.9% (95% CI: 82.5–98.1%) and 99.9% (95% CI: 97.7–100.0%), respectively. The difference was statistically significant (P = 0.002). Completion of treatment and Section IV of the Houpt scale were the most used efficacy criteria. Within the limitations of this systematic review, the present study provides important information on the efficacy rate of NOIS. However, further well-designed and well-documented clinical trials are required and there is a need to develop guidelines for standardization of criteria and definition of success in procedural sedation. Currently, completion of treatment is the most used parameter in clinical practice, though many others also do exist at the same time. To maximize NOIS efficacy, clinicians should strictly consider appropriate indications for the procedure.

Patient-Reported outcomes of pain care research in the adult emergency department: A scoping review

Despite more than 30 years of research, pain in the emergency department (ED) setting is frequently undertreated. EDs prioritise process measures that often have tenuous links to patient-reported outcomes. However, process measures, such as time to the administration of first analgesic medication, are neither direct objective measures of analgesia nor appropriate surrogate markers of pain relief. Since pain is a subjective symptom that lacks an objective measure, pain research in any clinical environment, including EDs, should rely upon patient-reported outcomes. This scoping review examined patient-reported outcomes (PROs) and patient-reported outcome measures (PROMs) of pain care in the adult emergency department at the micro, meso and macro-level over the last ten years. We reviewed pain care research conducted on adults in EDs over the last ten years and identified 57 articles using 14 patient-reported outcomes of pain care falling into five broad areas, most without validation or adaption to the ED setting. Despite efforts made to incorporate PROs and PROMs into acute pain care research in the ED over the last ten years, there is still no gold-standard PROM in widespread use. We recommend the adaptation of existing tools with rigorous validation in ED populations.

Approaching acute pain in emergency settings; European Society for Emergency Medicine (EUSEM) guidelines-part 2: management and recommendations

BACKGROUND

In Europe, healthcare systems and education, as well as the clinical care and health outcomes of patients, varies across countries. Likewise, the management of acute events for patients also differs, dependent on the emergency care setting, e.g. pre-hospital or emergency department. There are various barriers to adequate pain management and factors common to both settings including lack of knowledge and training, reluctance to give opioids, and concerns about drug-seeking behaviour or abuse. There is no single current standard of care for the treatment of pain in an emergency, with management based on severity of pain, injury and local protocols. Changing practices, attitudes and behaviour can be difficult, and improvements and interventions should be developed with barriers to pain management and the needs of the individual emergency setting in mind.

METHODS

With these principles at the forefront, The European Society for Emergency Medicine (EUSEM) launched a programme-the European Pain Initiative (EPI)-with the aim of providing information, advice, and guidance on acute pain management in emergency settings.

RESULTS AND CONCLUSIONS

This article provides treatment recommendations from recently developed guidelines, based on a review of the literature, current practice across Europe and the clinical expertise of the EPI advisors. The recommendations have been developed, evaluated, and refined for both adults and children (aged ≥ 1 year, ≤ 15 years), with the assumption of timely pain assessment and reassessment and the possibility to implement analgesia. To provide flexibility for use across Europe, options are provided for selection of appropriate pharmacological treatment.

Analgesic Effect of Nitrous Oxide/Oxygen Mixture for Traumatic Pain in the Emergency Department: A Randomized, Double-Blind Study

BACKGROUND

Acute pain is the most common complaint in Emergency Department (ED) admissions, and options for analgesia are limited. Nitrous oxide/oxygen possesses many properties showing it may be an ideal analgesic in the ED.

OBJECTIVES

The aim of this study is to evaluate the safety and analgesic effect of the fixed nitrous oxide/oxygen mixture for trauma patients in the ED.

METHODS

We enrolled 60 patients in this double-blind, randomized study. The treatment group received conventional pain treatment plus a mixture of 65% nitrous oxide/oxygen. The control group received the conventional pain treatment plus oxygen. Primary outcome was the reduction in pain intensity at 5 and 15 min after the start of intervention. Secondary outcomes include adverse events, physiological parameters, and satisfaction from both patients and health care professionals.

RESULTS

Initial pain scores for the nitrous oxide/oxygen group (6.0 [5.0-8.0]) and the oxygen group (6.75 [5.0-9.0]) were comparable (p = 0.57). The mean numerical rating scale scores at 5 min were 3.4 ± 1.8 and 7.0 ± 1.8 for nitrous oxide/oxygen and oxygen, respectively (p < 0.01). The mean pain intensity at 15 min in the treatment group was 3.0 ± 1.9, compared with 6.3 ± 2.2 in the control group (p < 0.01). Both patients' (8.0 [7.0-9.0] vs. 4.0 [2.0-6.0], p < 0.01) and physicians' (8.5 [8.0-9.0] vs. 4.0 [3.0-6.0], p < 0.01) satisfaction scores in the treatment group were significantly higher than the oxygen group. No serious adverse events were observed.

CONCLUSIONS

This study gives supporting evidence for the safety and effectiveness of using self-administered nitrous oxide/oxygen mixture in the ED for moderate-to-severe traumatic pain.

A fixed nitrous oxide/oxygen mixture as an analgesic for trauma patients in emergency department: study protocol for a randomized, controlled trial

BACKGROUND

Acute pain is always the most common complaint in Emergency Department admissions and options for analgesia are limited. Nitrous oxide/oxygen possess many properties showing it may be an ideal analgesic method for the Emergency Department; it is quick-acting, well-tolerated, and does not mask signs and symptoms. The aim of this study is to evaluate the safety and analgesic effect of the fixed nitrous oxide/oxygen mixture for trauma patients in a busy emergency environment.

METHODS

The randomized, double-blind, prospective, placebo-controlled study will be carried out in the Emergency Department of General Hospital of Ningxia Medical University. The target research objects are trauma patients who present to the Emergency Department and report moderate to severe intensities of acute pain. A total of 90 patients will be recruited and randomly assigned into the treatment and control group. The treatment group will receive conventional pain treatment plus nitrous oxide/oxygen mixture and the control group will receive conventional pain treatment plus oxygen. Neither patients, nor investigators, nor data collectors will know the nature of the gas mixture in each cylinder and the randomization list. Outcomes will be monitored at baseline(T0), 5 min (T1), and 15 min (T2) after the beginning of intervention and at 5 min post intervention (T3) for each group. The primary outcome is the level of pain relief after the initial administering of the intervention at T1, T2, and T3. Secondary outcomes include adverse events, physiological parameters, total time of the gas administration, satisfaction from both patients and healthcare professionals, and the acceptance of patients.

DISCUSSION

Our previous studies suggested that a fixed nitrous oxide/oxygen mixture was an efficacious analgesic for the management of burning dressing pain and breakthrough cancer pain. The results of this study will provide a more in-depth understanding of the effect of this gas. If this treatment proves successful, it could help to generate preliminary guidelines and be implemented widely in trauma patients with pain in Emergency Departments.

TRIAL REGISTRATION

Chinese Clinical Trial Register, ChiCTR-INR-16007807 . Registered on 21 January 2016.

Luxations aiguës d'épaule : évaluation rétrospective aux urgences et proposition d'un protocole de sédation procédurale

Introduction : Les luxations d'épaule sont des pathologies fréquentes aux urgences, parmi les plus douloureuses et pour lesquelles il n'existe pas de recommandations spécifiques. Elles représentent 45 % de l'ensemble des luxations. L'objectif principal de cette étude était d'analyser la gestion de la douleur dans cette pathologie.

Matériel et méthodes : Nous avons conduit une étude observationnelle, monocentrique et rétrospective colligeant 238 patients ayant consulté aux urgences pour une luxation aiguë d'épaule (01/01/2012-30/04/2015). Les luxations réduites spontanément, les luxations sur prothèse et les luxations chroniques étaient exclues de l'étude.

Résultats : Les luxations aiguës d'épaule étaient majoritairement réduites aux urgences (90 %, IC95 % : [86-94]). Il s'agissait d'une pathologie hyperalgique (Echelle numérique médiane : 8/10, [EIC : 6-9]) touchant plutôt les sujets jeunes (âge médian : 48 ans, EIC : 28-73). Il existait une grande hétérogénéité dans la répartition des antalgiques utilisés, le mélange équimolaire d'oxygène et de protoxyde d'azote (MEOPA) était l'antalgique le plus prescrit (50 % (IC95 % : [42-55])), suivi par le paracétamol (25 %) et le néfopam (15 %). Dans le sous-groupe des luxations compliquées d'une fracture, le MEOPA était également le plus prescrit. La répartition des autres antalgiques était par ailleurs similaire. Enfin, la comparaison entre les deux équipes médicales (urgentiste vs orthopédiste) ne retrouvait aucune différence de prescription en dehors du midazolam davantage utilisé par les urgentistes (16 % vs 4 %, p=0,001).

Conclusion : Il existait une grande hétérogénéité des pratiques et une sous-utilisation d'antalgiques et d'hypnotiques malgré des douleurs importantes dès l'admission. Un chemin clinique visant à améliorer cette prise en charge est proposé afin d'homogénéiser les pratiques.

A Review of Current and Emerging Approaches to Pain Management in the Emergency Department

INTRODUCTION

Pain is the most common symptom prompting an emergency department visit and emergency physicians are responsible for managing both acute pain and acute exacerbations of chronic pain resulting from a broad range of illnesses and injuries. The responsibility to treat must be balanced by the duty to limit harm resulting from analgesics. In recent years, opioid-related adverse effects, including overdose and deaths, have increased dramatically in the USA. In response to the US opioid crisis, emergency physicians have broadened their analgesic armamentarium to include a variety of non-opioid approaches. For some of these therapies, sparse evidence exists to support their efficacy for emergency department use. The purpose of this paper is to review historical trends and emerging approaches to emergency department analgesia, with a particular focus on the USA and Canada.

METHODS

We conducted a qualitative review of past and current descriptive studies of emergency department pain practice, as well as clinical trials of emerging pain treatment modalities. The review considers the increasing use of non-opioid and multimodal analgesic therapies, including migraine therapies, regional anesthesia, subdissociative-dose ketamine, nitrous oxide, intravenous lidocaine and gabapentinoids, as well as broad programmatic initiatives promoting the use of non-opioid analgesics and nonpharmacologic interventions.

RESULTS

While migraine therapies, regional anesthesia, nitrous oxide and subdissociative-dose ketamine are supported by a relatively robust evidence base, data supporting the emergency department use of intravenous lidocaine, gabapentinoids and various non-pharmacologic analgesic interventions remain sparse.

CONCLUSION

Additional research on the relative safety and efficacy of non-opioid approaches to emergency department analgesia is needed. Despite a limited research base, it is likely that non-opioid analgesic modalities will be employed with increasing frequency. A new generation of emergency physicians is seeking additional training in pain medicine and increasing dialogue between emergency medicine and pain medicine researchers, educators and clinicians could contribute to better management of emergency department pain.