Nitrous oxide misuse: a clue not to be missed in young patients with venous thromboembolism.

A 27-year-old man presented with altered mental status and unilateral right lower limb swelling. Brain imaging and cerebrospinal fluid analysis were unremarkable. He reported history of nitrous oxide misuse after he recovered from his delirium. The diagnosis of drug induced psychosis was made. The right lower limb swelling was found to be due to extensive deep vein thrombosis. In another case, a 21-year-old woman presented with headache, vomiting and dipoplia. Brain imaging showed extensive cerebral venous sinus thrombosis. She also misused nitrous oxide. Both cases had low-normal vitamin B12 and elevated methylmalonic acid, consistent with nitrous oxide misuse. The woman was found to have elevated homocysteine because of functional vitamin B12 deficiency. Homocysteine was not measured in the man. Raised homocysteine is associated with increased thrombosis risk. Fourteen cases of nitrous oxide misuse associated arterial and venous thrombosis have been reported. These two cases highlighted the importance of inquiring about recreational drug use in young patients who presented with apparently unprovoked venous thromboembolism.

Neurological and Psychological Characteristics of Young Nitrous Oxide Abusers and Its Underlying Causes During the COVID-19 Lockdown.

Background: The COVID-19 pandemic has a serious impact on the mental health of the public due to its economic and social impact. And psychological effects have led to drug and alcohol abuse. After the city lifted the lockdown, we consecutively encountered several young nitrous oxide abusers admitted to hospital for neurological treatment. Purpose: To inform physician decisions and social intervention, this observational study aimed at investigating the neurological and psychological characteristics of nitrous oxide abusers and its underlying causes during the COVID-19 lockdown. Methods: The nitrous oxide abusers who sought neurological treatment at our hospital between May 2020 and June 2020 were enrolled. Clinical data including socio-demographic, physical examination, laboratory examination, electromyography and neuroimaging were collected. Their motivations for inhaling nitrous oxide, knowledge about the nitrous oxide abuse and the accompanying of family were investigated face to face. Psychological status was assessed by the Symptom Checklist 90 (SCL-90) psychological evaluation. Results: Six nitrous oxide abusers were enrolled and the age was 22 ± 4.3. Clinical presentations included varying degrees of limb numbness and an ataxic gait. Laboratory examination revealed that all the patients did not have pernicious anemia, 4 patients had decreased vitamin B12 while 3 patients exhibited elevated homocysteine levels. MR of the spinal cord revealed that 4 patients had abnormal signals in the cervical spinal cord of high symmetry with splayed or inverted V sign after T2WI. Electromyogram (EMG) test showed 5 patients had peripheral nerve damage. The SCL-90 psychological evaluation results indicated that all patients had severe anxiety, depression and psychosis and they had severer psychological problems than ordinary citizens. Their motives for inhaling nitrous oxide are to relieve boredom, curiosity and buddy pressure. Their family spent <1 day per week to stay with them during city lockdown. Conclusion: The enrolled patients caused by abuse of nitrous oxide presented with symptoms of subacute combined with spinal degeneration. They had more serious psychological problems related to the COVID-19 pandemic. These cases make us value the psychological problems of young people under the outbreak and take multi-layered measures from families, schools (companies), hospitals, and governments to address it.

Possible impact of the COVID-19 pandemic on the recreational use of nitrous oxide in the Paris area, France.

INTRODUCTION: Recreational use of nitrous oxide (N2O) is increasing in Western countries, including France. During the COVID-19 pandemic, some authors warned that recreational N2O use could increase further as the supply of illicit drugs was impacted by various containment measures. METHODS: We retrospectively analyzed N2O exposures reported to the Paris Poison Control Center (France) from 2010/01/01 to 2021/04/15. The Poison Severity Score was used to grade severity. RESULTS: During the study period, 93 cases of N2O recreational exposures were reported (male/female ratio: 1.1; median age: 20.9 years range: [14.8-49.0]). The first case was reported in 2012, 84/93 (90%) and 65/93 (70%) were reported since 2019 and March 17th 2020 (first lockdown in France) respectively. Most of the patients were symptomatic (88/93; 95%) and developed neurological symptoms (78/93; 84%). Among the fourteen patients who developed moderate to severe symptoms, eleven were reported after March 2020. CONCLUSION: Despite a marked increase in recreational N2O exposures during the COVID-19 pandemic, the exact impact of COVID-19 on this increase remains to be determined as it was observed from 2019.

Burn injury from filling balloons with nitrous oxide.

We present the case of a female teenager who sustained nitrous oxide burns to the medial aspect of both thighs from contact with a nitrous oxide canister being used to fill balloons. There was a delay in presentation as the injury was not initially recognised. These burns were initially assessed as being superficial partial-thickness burns but took a prolonged time to heal despite regular wound care. This was complicated by a lack of adherence to recommended treatment for much of the patient care as well as the patient testing positive for COVID-19 during their management, which prevented surgery and significantly extended time to healing. While small numbers of similar cases have been previously described this is the first reported case outside of the Netherlands and in a child. Being aware of such cases ensures early referral to specialist burn care for appropriate management to give patients the best possible outcome.

Neurological consequences of recreational nitrous oxide abuse during SARS-CoV-2 pandemic.

INTRODUCTION: Recreational use of nitrous oxide (N2O) is a growing practice in France and all around the world and is often associated with neurological complications. We report detailed clinical and paraclinical presentations of 12 patients with combined degeneration of the spinal cord and peripheral neuropathies in relation to N2O consumption, possibly favored by lockdowns due to SARS-CoV-2 pandemic. RESULTS: With variable levels of consumption, the 12 patients presented spinal cord and/or peripheral nerve damage, with mostly motor and ataxic symptoms, motor axonal nerve damage, and medullary T2-weighted hyperintensities on MRI. There was a clear improvement in symptoms after vitamin B12 substitution, although some sequelae remained, particularly sensory. DISCUSSION: We report detailed clinical, electrophysiological, radiological, and biological consequences of N2O abuse in 12 patients. Our data support the clinical and paraclinical observations reported in the literature. The mechanisms of neurological N2O toxicity are still debated. There is currently no precise recommendation on the therapeutic management. The clinical evolution after vitamin B12 substitution seems sufficient but could depend on early management. Effective messages targeting at risk population, but also the health professionals involved, seem crucial as does a better legal framework for this growing practice.

A rise in cases of nitrous oxide abuse: neurological complications and biological findings.

BACKGROUND: The recent lockdown due to the COVID-19 pandemic has been linked to a higher incidence of psychiatric manifestations and substance abuse. The recreative use of nitrous oxide is more and more widespread and neurological complications are frequent. METHODS: We report clinical characteristics and biological findings of five consecutive patients presenting to our tertiary care center between April 2020 and February 2021 with various neurological symptoms occurring after recent nitrous oxide abuse. RESULTS: Our patients presented with subacute combined degeneration of the spinal cord (4/5 patients) or with acute inflammatory demyelinating polyneuropathy (1/5 patients). No patient had reduced vitamin B-12 titer, but all had elevated blood levels of homocysteine and methylmalonic acid. This reflects the functional deficit in vitamin B-12 that can be linked to nitrous oxide consumption. After vitamin B-12 supplementation, clinical signs regressed at least partially in all 5 patients. CONCLUSION: We report an elevated incidence of neurological complications of nitrous oxide abuse occurring during the recent COVID-19 lockdown. Nitrous oxide abuse should be tracked down in patients presenting with compatible neurological symptoms and elevated homocysteinemia. Vitamin B-12 should be supplemented as soon as the diagnosis is made.

Clinical effectiveness of inhalation conscious sedation with nitrous oxide and oxygen for dental treatment in uncooperative paediatric patients during COVID-19 outbreak.

AIM: The aim of this study was to evaluate the features of inhalation conscious sedation for urgent dental treatments in uncooperative paediatric patients during COVID-19 outbreak. MATERIALS AND METHODS: Forty-two uncooperative patients, attending primary and secondary schools, were submitted to emergency dental treatments with inhalation conscious sedation using nitrous oxide and oxygen during COVID-19 pandemic. Collected data included: number of working sessions, success/failure, adverse events, side effects, number of teeth treated; type of dental procedure. Parents filled in an e-mailed questionnaire on post-discharge children status to evaluate: pain; crying; fever; vomiting; headache; drowsiness; excitability; irritability; ability to eat; need for drugs. RESULTS: One working session was carried out in 29 patients, 2 working sessions were carried out in 6 patients and 3 working sessions were carried out in 7 patients. Success rate was 87.1%. In relation to success, there was no statistically significant difference between males and females, healthy and disabled patients, respectively; while there was a statistically significant difference between patients attending primary and secondary schools (p=0.023). No adverse events occurred. The most frequent side effect was nausea. In relation to side effects, there was no statistically significant difference between males and females, healthy and disabled patients, patients attending primary and secondary schools, respectively. In relation to e-mailed questionnaires on post-discharge children status, 29.6% of the patients had pain, 22.2% vomited, 14.8% had headache, 18.5% experienced drowsiness, 29.6% failed to eating normally, 35.2% needed to take drugs. None of the patients cried, had a fever, exhibited irritability and excitability. CONCLUSION: Inhalation conscious sedation is a safe, practical and effective procedure with minimal side effects to perform emergency dental treatments in uncooperative paediatric patients during COVID-19 outbreak.