ABSTRACT
Purpose: The purpose of this study was to evaluate the environmental impact of travel and anesthetic gas emissions associated with treating early childhood caries at a single institution. Methods: Outpatient preventive, treatment, and modeled general anesthesia (GA) cases in children 71 months old and younger were included in this retrospective chart review. The main outcomes were kilograms of carbon dioxide equivalents (kgCO2e) for travel- and anesthetic gas-related emissions. Descriptive statistics and non-parametric tests were used. Results: Most subjects had a caries treatment visit (n equals 3,630 out of 5,767), and nine percent of treatment visits (n equals 353 out of 3,630) received nitrous oxide (N2O), which added 29.4 kgCO2eto the visit emissions. Children without caries treatment had lower travel-related emissions (median equals 7.5 kgCO2e; interquartile range [IQR] equals 7.6) than children with caries treatment (median without N2O equals 8.7 kgCO2e; IQR equals 18.2; median with N2O equals 8.4 kgCO2e; IQR equals 10.3). Modeled GA travel emissions were estimated at 16.4 kgCO2e (IQR equals 21.9) with between 3.8-12.9 kgCO2e in anesthetic gas emissions. Total emissions were greatest for N2O treatment visits (median equals 43.3 kgCO2e; IQR equals 22.8). Conclusions: Travel-related emissions were greatest for children requiring caries treatment. Minimizing patient travel may reduce environmental impact. Nitrous oxide contributes a significant amount to a dental visit???s environmental impact. Community-focused models of care and applying systematic and practical case selection to reduce excess N2O emissions could reduce dental care-related carbon emissions.
Subject(s)
Anesthetics, Inhalation , Dental Caries , Nitrous Oxide , Humans , Dental Caries/prevention & control , Child, Preschool , Retrospective Studies , Nitrous Oxide/analysis , Nitrous Oxide/administration & dosage , Infant , Anesthetics, Inhalation/adverse effects , Anesthetics, Inhalation/administration & dosage , Female , Male , Carbon Dioxide/analysis , Anesthesia, General , Anesthesia, Dental , Dental Care for ChildrenABSTRACT
BACKGROUND: Pharmacological methods, specifically sedatives, have gained popularity in managing the behavior of children during dental appointments. AIM: The aim of this study was to compare 1 m/kg intranasal dexmedetomidine, 0.3 mg/kg intranasal midazolam, and nitrous oxide in evaluating the level of sedation, behavior of the child, onset of sedation, physiologic signs, and adverse effects. MATERIALS AND METHODS: In this cross-over trial, 15 children aged 6-8 years were randomized to receive intranasal atomized dexmedetomidine, intranasal atomized midazolam, and inhalation nitrous oxide at three separate visits. After administering the sedative agent, a single pulpectomy was performed during each appointment, and the outcomes were recorded. The washout period between each visit was 1 week. RESULTS: All three sedative agents were equally effective in controlling overall behavior. Dexmedetomidine showed lower sedation level scores (agitated; score 9) than the other groups. There was a statistically significant difference in the onset of sedation, with dexmedetomidine having the longest onset of 36.2 ± 9.47 min. Coughing and sneezing were predominantly observed after administration of intranasal midazolam. Oxygen saturation levels were statistically lower in the intranasal midazolam group during local anesthesia administration and post-treatment. CONCLUSION: 0.3 mg/kg intranasal midazolam is as effective as nitrous oxide sedation for controlling behavior and providing adequate sedation in pediatric dental patients. However, 1 m/kg dexmedetomidine did not provide the same level of sedation and had a significantly longer onset. 0.3 mg/kg intranasal midazolam is an effective alternative to nitrous oxide sedation in anxious children.
Subject(s)
Administration, Intranasal , Conscious Sedation , Cross-Over Studies , Dental Anxiety , Dexmedetomidine , Hypnotics and Sedatives , Midazolam , Nitrous Oxide , Humans , Nitrous Oxide/administration & dosage , Midazolam/administration & dosage , Child , Hypnotics and Sedatives/administration & dosage , Dexmedetomidine/administration & dosage , Conscious Sedation/methods , Male , Female , Dental Anxiety/prevention & control , Anesthesia, Dental/methods , Anesthetics, Inhalation/administration & dosage , Dental Care for Children/methods , Child Behavior/drug effects , Pulpectomy/methodsABSTRACT
AIMS: To describe the clinical features and outcomes of patients with myelopathy and neuropathy due to recreationally inhaled nitrous oxide. METHODS: We identified patients presenting with nitrous oxide-associated myelopathy from an electronic database of all discharges in a large tertiary hospital between 2016 and 2023. Demographics, clinical features and the results of investigations were recorded. The primary outcome was modified Rankin Scale score (mRS) at least 3 months after hospital discharge where available. RESULTS: There were 12 patients identified, six women, mean (SD) age 27.5 (5.1) years, range 19-47 years. The most common symptoms were numbness, weakness and mental state changes. Four patients used large amounts of inhaled nitrous oxide and also took over-the-counter vitamin B12 supplements. The median (range) hospital length of stay was 8.5 (2-56) days. Functional independence at last assessment (median [range] of 3 [1-34] months after discharge) was achieved in nine of the patients, with three requiring ongoing support for activities of daily living (mRS ≥3). CONCLUSION: Nitrous oxide abuse and its neurological complications are an important public health issue. Clinicians should be aware that some patients who use large amounts of nitrous oxide may self-supplement vitamin B12.
Subject(s)
Nitrous Oxide , Spinal Cord Diseases , Humans , Nitrous Oxide/adverse effects , Nitrous Oxide/administration & dosage , Female , Adult , Male , Middle Aged , Spinal Cord Diseases/chemically induced , Young Adult , Vitamin B 12/administration & dosage , Substance-Related Disorders/epidemiology , Anesthetics, Inhalation/adverse effects , Anesthetics, Inhalation/administration & dosage , Retrospective Studies , Length of Stay/statistics & numerical dataSubject(s)
Nitrous Oxide , Humans , Nitrous Oxide/adverse effects , Nitrous Oxide/administration & dosage , Subacute Combined Degeneration/etiology , Subacute Combined Degeneration/chemically induced , Male , Spinal Cord Diseases/chemically induced , Spinal Cord Diseases/etiology , Spinal Cord Diseases/diagnostic imagingABSTRACT
Climate change represents an urgent global threat. Without action, rising temperatures resulting from human activity will increasingly affect our health and wellbeing through changing patterns of disease, extreme weather events and availability of resources. Expedient decarbonisation of the UK economy is an ambitious goal to which we must all contribute.The NHS aims to be the world's first net-zero health service and reach carbon-neutral status by 2040. Dental services are particularly resource-intensive. Some dental anxiety management techniques have a disproportionately high impact on the environment relative to their usage. Inhalation sedation with nitrous oxide is one such example.Nitrous oxide is a greenhouse gas almost 300 times more potent than carbon dioxide, but its utility to facilitate dental treatment for anxious and vulnerable patients is well-documented. This paper balances the health utility with environmental and social harm of continuing to use nitrous oxide and suggests evidence-based methods we can apply to limit the environmental impact of sedation services.
Subject(s)
Climate Change , Conscious Sedation , Dental Anxiety , Nitrous Oxide , Humans , Dental Anxiety/prevention & control , Conscious Sedation/methods , Nitrous Oxide/administration & dosage , Nitrous Oxide/therapeutic use , Anesthetics, Inhalation/administration & dosage , United Kingdom , Anesthesia, Dental/methodsABSTRACT
BACKGROUND: Over the last decade, there has been an emerging trend of recreational misuse of several drugs and inhaled solvent including ethyl chloride. This case report follows CARE guidelines and highlights, with supporting video, the neurological features of ethyl chloride intoxication. CASE PRESENTATION: A 48-year-old man was seen for the sudden occurrence of an unsteady gait with dizziness. His only medical history was a chronic and treated HIV infection without any complications. Clinical examination revealed a cerebellar syndrome associated with impairment of short-term memory. Biological and radiological workups were normal. After several days, the patient recalled ethyl chloride inhalation. He fully recovered after being discharged from hospital. CONCLUSION: Clinicians should recognise the clinical features and neurological manifestations of ethyl chloride intoxication due to the potential fatal cardiovascular complications of this intoxication.
Subject(s)
Ethyl Chloride , Nitrous Oxide , Humans , Male , Middle Aged , Ethyl Chloride/adverse effects , Nitrous Oxide/adverse effects , Nitrous Oxide/administration & dosageABSTRACT
Nitrous oxide is a widely used and well-established form of inhalation sedation in dentistry. Its properties have a wide margin of safety and allow for anxious, paediatric and adult patients to receive dental treatment with minimal impact upon discharge. Nitrous oxide has drawbacks, however, including its environmental impact and need for specialist equipment. Methoxyflurane is another drug which could prove to be an alternative to nitrous oxide. Methoxyflurane's use has proved popular within emergency medicine in Australia and New Zealand for its potent analgesic effects and recognition of its anxiolytic effect. As a result, its use in invasive outpatient procedures has now become popular. Unfortunately, there is very limited evidence of its use within dentistry as a form of inhalation sedation and analgesic. A wider evidence base should be established, as methoxyflurane could prove to be an effective and environmentally friendly alternative to nitrous oxide.
Subject(s)
Anesthesia, Dental , Anesthetics, Inhalation , Methoxyflurane , Nitrous Oxide , Humans , Anesthesia, Dental/methods , Anesthetics, Inhalation/administration & dosage , Conscious Sedation/methods , Isoflurane/administration & dosage , Methoxyflurane/administration & dosage , Methoxyflurane/therapeutic use , Methoxyflurane/pharmacology , Nitrous Oxide/administration & dosageABSTRACT
BACKGROUND: Climate change has emerged as the single biggest global health threat of the twenty-first century. Nitrous oxide accounts for the largest carbon footprint amongst our use of anaesthetic gas. It is a potent greenhouse gas possessing a global warming potential of approximately 265 times that of carbon dioxide. Despite recent curtailment of its use, it remains extensively employed as an analgesic for women in labour. OBJECTIVES: Assessment of the opinions of post-natal women and staff on nitrous oxide use and to investigate whether knowledge of its environmental harm would influence their choice of labour analgesia. DESIGN: Postnatal women and healthcare staff were invited to participate in a survey of nitrous oxide use as a labour analgesic and knowledge of its effect of the environment. SETTING: A single-centre study in a major obstetric tertiary referral centre in Ireland in 2021. MAIN OUTCOME MEASURES: To evaluate the awareness and perceptions of postnatal women and staff regarding the environmental impact of nitrous oxide and if it would affect their decision to use it in the future. RESULTS: One hundred postnatal women and 50 healthcare staff completed the survey. One hundred and six post-natal women were invited to complete the survey, resulting in a response rate of 94%. Knowledge of nitrous oxide's environmental impact was low. After receiving information, 46% of patients were more inclined to seek epidural or request it earlier (54%) to limit their nitrous oxide use, while 51% would choose an alternative analgesia to avoid nitrous oxide altogether. Overwhelmingly, 99% believed they had the right to know about these harmful effects when choosing an analgesic option. CONCLUSIONS: Patients should be informed of the environmental impact of nitrous oxide antenatally, empowering them to make informed decision on a climate friendly analgesic option if they wish.
Subject(s)
Analgesia, Obstetrical , Nitrous Oxide , Humans , Nitrous Oxide/administration & dosage , Nitrous Oxide/adverse effects , Female , Pregnancy , Analgesia, Obstetrical/methods , Adult , Surveys and Questionnaires , Anesthetics, Inhalation/administration & dosage , Anesthetics, Inhalation/adverse effects , Ireland , Health Personnel , Health Knowledge, Attitudes, Practice , Young Adult , Attitude of Health PersonnelSubject(s)
Anesthetics, Inhalation , Nitrous Oxide , Nitrous Oxide/history , Nitrous Oxide/administration & dosage , Nitrous Oxide/adverse effects , Humans , Anesthetics, Inhalation/history , Anesthetics, Inhalation/administration & dosage , History, 20th Century , Administration, Inhalation , History, 19th CenturyABSTRACT
The formation of pneumoperitoneum involves the process of inflating the peritoneal cavity during laparoscopic and typically uses CO2 as the insufflation gas. This review aims to identify ideal gas mixtures for establishing the pneumoperitoneum with animal and human studies undertaken up to the writing of this review. A systematic search of PubMed, OVID, and clinicaltrials.gov was performed to identify studies on the utilisation of mixed gases in laparoscopic surgery, including non-randomised/randomised trials, animal and human studies, and studies with inflating pressures between 12 and 16 mmHg. ROBINS-I and RoB2 tool was used to assess the risk of bias. A narrative synthesis of results was performed due to the heterogeneity of the studies. 5 studies from the database search and 5 studies from citation search comprising 128 animal subjects and 61 human patients were found. These studies collated results based on adhesion formation (6 studies), pain scores (2 studies) and other outcomes, with results favouring the use of carbon dioxide + 10% nitrous oxide + 4% oxygen. This has shown a significant reduction in adhesion formation, pain scores and inflammation. The use of this gas mixture provides promising results for future practice. Several of the studies available require larger sample sizes to develop a more definitive answer on the effects of different gas mixtures. Furthermore, the number of confounding factors in randomised trials should be reduced so that each component of the current suggested gas mixture can be tested for safety and efficacy.
Subject(s)
Carbon Dioxide , Laparoscopy , Nitrous Oxide , Pneumoperitoneum, Artificial , Animals , Humans , Mice , Carbon Dioxide/administration & dosage , Insufflation/methods , Laparoscopy/methods , Minimally Invasive Surgical Procedures/methods , Models, Animal , Nitrous Oxide/administration & dosage , Oxygen/administration & dosage , Pneumoperitoneum, Artificial/methods , Pneumoperitoneum, Artificial/adverse effects , Tissue Adhesions/prevention & controlABSTRACT
BACKGROUND: The recreational use of nitrous oxide (N2O) has increased in recent years with a noticeable surge in the incidence of nitrous oxide-related myeloneuropathy. OBJECTIVES: To raise awareness of increasing myeloneuropathy due to recreational nitrous oxide misuse in Israel. METHODS: We conducted a case series documenting the clinical and investigative features of eight patients presenting with nitrous oxide-induced myeloneuropathy who were admitted to our departments. RESULTS: Paresthesia was the chief complaint in all patients, with sensory gait ataxia being a common feature, which was often accompanied by Romberg's sign and mild lower limb weakness. Vitamin B12 levels were below the normal range in seven patients, accompanied by elevated homocysteine and methylmalonic acid levels. Magnetic resonance imaging scans revealed hyperintense signals in the dorsal columns of the cervical spine. All patients improved following vitamin B12 injections. CONCLUSIONS: Enhancing awareness, prompting the use of appropriate investigations, and advocating for timely treatment are needed to overcome the risks associated with nitrous oxide misuse.
Subject(s)
Magnetic Resonance Imaging , Nitrous Oxide , Vitamin B 12 , Humans , Nitrous Oxide/adverse effects , Nitrous Oxide/administration & dosage , Male , Adult , Vitamin B 12/administration & dosage , Female , Israel/epidemiology , Magnetic Resonance Imaging/methods , Spinal Cord Diseases/chemically induced , Paresthesia/chemically induced , Paresthesia/diagnosis , Middle Aged , Recreational Drug Use , Gait Ataxia/chemically induced , Gait Ataxia/etiology , Young Adult , Substance-Related Disorders/complications , Vitamin B 12 Deficiency/chemically induced , Vitamin B 12 Deficiency/diagnosisABSTRACT
BACKGROUND AND AIM: Recreational use of nitrous oxide (N2O) has been associated with the development of severe nitrous oxide-induced neuropathy (N2On). Follow-up of these patients poses challenges, and their clinical progression remains largely unknown. The identification of prognostic factors is made difficult by the lack of standardized longitudinal assessments in most studies. The objective was to document the course of neuropathy through systematic follow-up assessments in N2On patients to identify prognostic factors for persistent disability after 6 months. METHODS: We gathered demographic, clinical, biological, and electrophysiological data from N2On patients hospitalized in the Referral center in Marseille, both at baseline and during a standardized follow-up assessment at 6 months. RESULTS: We retrospectively included 26 N2On patients (mean age 22.6 ± 4.4). Significant improvements were observed in all main clinical scores including Rankin, ONLS, and MRC testing (p < .01). Electrophysiological studies (EDX) revealed a predominantly motor neuropathy with marked reduction in CMAP in the lower limbs at baseline, and no significant improvement in motor parameters (p = .543). Rankin score at 6 months correlated with the initial weekly N2O consumption (r = .43, p = .03) and the CMAP sum score in the lower limbs at the first EDX (r = -.47, p = .02). Patients with and without myelitis showed similar Rankin and ONLS score after 6 months. INTERPRETATION: The clinical course generally improved favorably at 6 months with notable amelioration in the primary disability scores, sensory deficits, and ataxia. However, distal motor impairment associated with peripheral neuropathy persisted, with distal axonal loss emerging as the main prognostic factor for long-term disability in these young patients.
Subject(s)
Nitrous Oxide , Peripheral Nervous System Diseases , Humans , Nitrous Oxide/adverse effects , Nitrous Oxide/administration & dosage , Male , Female , Adult , Young Adult , Retrospective Studies , Prognosis , Longitudinal Studies , Peripheral Nervous System Diseases/chemically induced , Peripheral Nervous System Diseases/physiopathology , Peripheral Nervous System Diseases/diagnosis , Follow-Up Studies , Adolescent , Neural Conduction/physiology , Neural Conduction/drug effectsABSTRACT
BACKGROUND: Nitrous oxide use is shifting from general anesthesia to sedation and pain control. Interest in novel uses of nitrous oxide in psychiatry is also growing. Thus, understanding the consequences of using nitrous oxide remains relevant. Previous quantitative research might not have fully captured the whole spectrum of nitrous oxide, whereas qualitative analysis can provide a more comprehensive description. This qualitative study aims to describe the subjective experiences of nitrous oxide use in healthy volunteers who have no prior history of recreational substance misuse. METHODS: Twenty healthy male volunteers inhaled 50% nitrous oxide for 20 min. Females were excluded due to higher incidence of nausea with nitrous oxide. Afterwards, all participants answered an open-ended question about their experiences during sedation. The answers were then analyzed with inductive qualitative content analysis to identify emergent subcategories, categories, and overarching themes. RESULTS: We identified two themes: nitrous oxide is mind-altering and produces sensory overload. The mind-altering properties were represented by dreamlike states and heightened emotions. Dreamlike states comprised changes in consciousness and scary, bizarre, or transcendental dreams. Pleasant dreams were not reported. Heightened emotions included euphoria, anxiety, and fear of losing control. Sensory overload consists of distorted perception, bodily sensations, and a heightened sense of surroundings. CONCLUSIONS: Experiences under nitrous oxide sedation are extremely variable and not always pleasant. These findings can improve our understanding of the likes/dislikes of patients undergoing nitrous oxide sedation. Further qualitative studies should focus on the experiences of other groups, such as children or women in labor.
Subject(s)
Anesthetics, Inhalation , Nitrous Oxide , Humans , Nitrous Oxide/administration & dosage , Male , Adult , Qualitative Research , Young Adult , Emotions/drug effects , Dreams/drug effects , Healthy VolunteersABSTRACT
STUDY OBJECTIVE: Uptake of intrauterine devices (IUDs) in the adolescent population may be limited by anxiety and pain anticipated during the insertion procedure. Our institution offers conscious sedation for IUD insertion to mitigate this concern. The objective of this study was to identify characteristics and outcomes of teens choosing between two types of conscious sedation for insertion of a levonorgestrel IUD. METHODS: This was a single-site, retrospective cohort study over a one year period, reviewing the electronic medical records of patients who had undergone an attempted IUD insertion using conscious sedation. Conscious sedation included nitrous gas (termed "light" sedation) or intravenous midazolam and fentanyl (termed "moderate" sedation). Patient demographic characteristics and medical and gynecological histories were analyzed. RESULTS: There were 69 attempted IUD insertions during the study period. Most patients (75.36%) were placed under light sedation, and 92.75% were successfully inserted. The only significant factor associated with choice in the type of conscious sedation was previous sexual activity, which increased the odds by 10.0 that the patient would choose light sedation (95% CI, 1.23-81.34; P = 0.031). Differences between other factors (age, history of sexual assault, tampon use, and gender identity) were not statistically significant between successful and failed insertions. CONCLUSION: In conclusion, history of sexual activity significantly differed between patients in our cohort who selected light sedation over moderate sedation. No other factors influenced the choice in sedative or success of IUD insertion. Knowing the characteristics of patients who choose nitrous versus intravenous sedation, and how it relates to successful insertion, may help guide pre-procedural counseling for patients regarding sedation for IUD insertion.
Subject(s)
Conscious Sedation , Fentanyl , Humans , Female , Conscious Sedation/methods , Retrospective Studies , Adolescent , Fentanyl/administration & dosage , Nitrous Oxide/administration & dosage , Midazolam/administration & dosage , Hypnotics and Sedatives/administration & dosage , Cohort Studies , Sexual Behavior , Intrauterine Devices , Intrauterine Devices, Medicated , Clinical Decision-MakingABSTRACT
PURPOSE: This paper reports a life cycle impact assessment (LCIA) to calculate the environmental footprint of a dental appointment using N2O, comparing single-use equipment with reusable equipment. Nitrous oxide (N2O) is used successfully in dentistry to provide sedation and pain relief to anxious patients, most commonly in children. However, N2O is a powerful climate pollutant 298 times more damaging than carbon dioxide over a 100-year estimate. METHODS: The functional unit chosen for this LCIA was 30 min delivery of N2O to oxygen in a 50:50 ratio at 6 L per minute flow rate as inhalation sedation to one patient. Two types of equipment were compared to deliver the anaesthetic gas: reusable and disposable items. RESULTS: The use of disposable equipment for N2O sedation produces a significantly larger environmental impact across nearly all of the environmental impact scores, but the overall global warming potential is comparable for both types of equipment due to the vast environmental pollution from N2O itself. CONCLUSION: N2O sedation is a reliable treatment adjunct but contributes to climate change. Single-use equipment has a further deleterious effect on the environment, though this is small compared to the overall impact of N2O. Dental priorities should be to deliver safe and effective care to patients that protects staff, minimises waste and mitigates impact on the environment alongside promoting research into alternatives.
Subject(s)
Anesthesia, Dental , Anesthetics, Inhalation , Conscious Sedation , Nitrous Oxide , Nitrous Oxide/administration & dosage , Humans , Anesthetics, Inhalation/administration & dosage , Anesthesia, Dental/instrumentation , Disposable Equipment , Equipment Reuse , Global Warming/prevention & controlABSTRACT
General anesthesia (GA) is typically recommended for category 1 emergency cesarean delivery (CD). For categories 2-4 emergencies, either regional or GA can be used. The factors influencing the choice of anesthetic technique in these categories remain poorly understood. We analyzed the association between the type of labor analgesia and subsequent anesthetic techniques employed for intrapartum categories 2 and 3 CD. In a prospective longitudinal cohort study, 300 women were consequently enrolled and categorized according to Lucas's classification of CD urgency. The techniques of anesthesia (GA, spinal, and epidural anesthesia [EA]) employed for CD were analyzed with respect to labor analgesia methods (remifentanil patient-controlled analgesia [remifentanil-PCA], EA, and nitrous oxide [N2O]). EA was the most frequent analgesic option (43.8%), followed by remifentanil-PCA (20.7%) and N2O (5.1%), while 30.4% of parturient women received no analgesia. All anesthetic methods showed a significant relationship with analgesic modalities (P < 0.001). Remifentanil-PCA was associated with a higher incidence of GA. Contraindication to EA was the primary factor related to the transition from remifentanil-PCA to GA. Most parturients who received EA were successfully converted to EA. Spinal anesthesia was the most common technique in women using N2O and those without labor analgesia. GA was associated with lower 5-min Apgar scores. The method of labor analgesia was associated with the anesthesia technique employed for categories 2 and 3 CD. This finding may guide patient counseling and intrapartum anesthetic planning. However, the analysis should be cautiously interpreted as the selection of anesthesia is a complex decision influenced by several clinical considerations.
Subject(s)
Cesarean Section , Humans , Female , Pregnancy , Cesarean Section/methods , Adult , Prospective Studies , Analgesia, Obstetrical/methods , Analgesia, Patient-Controlled/methods , Remifentanil/administration & dosage , Nitrous Oxide/administration & dosage , Longitudinal Studies , Labor, Obstetric/drug effects , Labor, Obstetric/physiology , Anesthesia, Obstetrical/methods , Anesthesia, General/methodsABSTRACT
BACKGROUND: Pediatric patients undergoing minor, but painful procedures in an Emergency Department (ED) need adequate relief of pain and distress to prevent long term negative effects and adversely impact procedures. Inhaled nitrous oxide (N2O) is a needle-free pain management option. We conducted a systematic review to determine whether N2O is as effective as local anesthesia in minor procedures. The purpose of this study was to evaluate available evidence regarding analgesic effectiveness of N2O in pediatric patients. METHODS: We searched MEDLINE, Embase, Cochrane and Cinahl databases for controlled trials published in English with pediatric patients in an ED treated with N2O compared to local anesthesia and with pain as primary outcome. Adverse events was one of the secondary outcomes. The GRADE system was used to rate the overall quality of evidence. RESULTS: We included seven studies with a total of 371 patients. Two studies showed N2O was equally effective in pain treatment as local anesthesia. Five studies showed N2O combined with local anesthesia is more effective in reducing pain than local anesthesia alone. None of the included studies reported major adverse effects. The quality of evidence is low. CONCLUSIONS: N2O can have an important contribution in pain management, but should be combined with local anesthesia for optimal pain management in pediatric patients undergoing minor, but painful procedures in an ED. LEVEL OF EVIDENCE: IV.