Is ethyl chloride the new nitrous oxide? A case report.

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.

Machine learning-driven identification of early-life air toxic combinations associated with childhood asthma outcomes.

Air pollution is a well-known contributor to asthma. Air toxics are hazardous air pollutants that cause or may cause serious health effects. Although individual air toxics have been associated with asthma, only a limited number of studies have specifically examined combinations of air toxics associated with the disease. We geocoded air toxic levels from the US National Air Toxics Assessment (NATA) to residential locations for participants of our AiRway in Asthma (ARIA) study. We then applied Data-driven ExposurE Profile extraction (DEEP), a machine learning-based method, to discover combinations of early-life air toxics associated with current use of daily asthma controller medication, lifetime emergency department visit for asthma, and lifetime overnight hospitalization for asthma. We discovered 20 multi-air toxic combinations and 18 single air toxics associated with at least 1 outcome. The multi-air toxic combinations included those containing acrylic acid, ethylidene dichloride, and hydroquinone, and they were significantly associated with asthma outcomes. Several air toxic members of the combinations would not have been identified by single air toxic analyses, supporting the use of machine learning-based methods designed to detect combinatorial effects. Our findings provide knowledge about air toxic combinations associated with childhood asthma.

Acute reversible neurologic deficits due to ethyl chloride sniffing: a case report and review of literature.

Ethyl chloride (CH3CH2Cl) or chloroethane is a colorless volatile halogenated hydrocarbon gas found in many commercially available solvents, and it may be used as an inhalant of abuse. Neurologic toxicity has been reported, as well as deaths. We present a case of a 47-year-old HIV-positive man who presented with acute reversible neurologic deficits secondary to inhalational exposure to ethyl chloride. Laboratory studies and neuroimaging are nondiagnostic in ethyl chloride-induced neurotoxicity and thus requires a high index of clinical suspicion. The mainstay of treatment is supportive with withdrawal of the offending agent and observation for resolution of neurologic symptoms.

Ocular surface frostbite secondary to ethyl chloride spray.

CONTEXT: Ethyl chloride (EC) is a fast-acting vapo-coolant spray that provides rapid, transient, local analgesia for minor invasive procedures. Although the application of EC has decreased, it can be used as a cryoanalgesic agent in minor surgical procedures. OBJECTIVE: Despite the widespread use of EC as a local anesthetic, there are few reported cases of serious adverse side effects. MATERIAL AND METHODS: We report a 67-year old otherwise healthy man who underwent excision of a papilloma on his superior right eyelid by a general practitioner at a primary care center. The lesion was removed by curettage after slight freezing with EC spray. This chemical agent was applied without the adequate eye protection, and eight hours later the patient presented an acute frost injury of ocular surface. RESULTS: Urgent treatment included copious irrigation of the affected eye, especially the conjunctival fornices, corticosteroid (prednisone) and antibiotic (neomycin) ointment. A week later, the eyelid lesion and keratoconjunctivitis had resolved but evidence of early cicatrization involving the inferior conjucntival fornix and symblepharon formation were present. DISCUSSION: To the best of our knowledge, this is the first reported case of an acute burn of the ocular surface following EC spray exposure. CONCLUSION: EC should be avoided for short-term local anesthesia in the periocular region to prevent this serious complication.

Allergic contact dermatitis from ethyl chloride and benzocaine.

Ethyl chloride (EC) or chloroethane (C2H5Cl) is a volatile halogenated hydrocarbon. Reports of contact sensitivity to this gas are infrequent considering its widespread use as a local anesthetic, and it may have a relatively low sensitization potential. Benzocaine is another local anesthetic derivative of the ethyl ester of para-aminobenzoic acid, previously reported as a causative agent of delayed hypersensitivity reactions. We present a patient who developed a generalized itching dermatitis after the application of a medical aerosol containing EC, as well as facial angioedema and tongue swelling after the local application of benzocaine. Patch-test results were positive for EC "as is" (++), benzocaine 5% in petrolatum (++), and caine mix (+++) at 96 hours (day 4). The possibility of cross-sensitization between both drugs would not have been chemically plausible. We report the first published clinical case of contact allergic dermatitis from two chemically unrelated local anesthetics (EC and benzocaine) in the same patient.

Acute inhalant-induced neurotoxicity with delayed recovery.

OBJECTIVE: To report a case of neurotoxicity and subsequent hospitalization due to abuse of an ethyl chloride inhalant. CASE SUMMARY: A 41-year-old African American male presented to the emergency department due to mental status changes and an inability to walk. After the blood alcohol and urine drug screen returned negative, a family member revealed that the patient frequently abused an inhalant containing the volatile solvent ethyl chloride. DISCUSSION: Inhalant abuse is common and is facilitated by the widespread availability of volatile solvents that have legitimate commercial or household uses. Most inhalants are central nervous system depressants and are highly lipophilic. Maximum Impact, which contains ethyl chloride, is sold in stores and is readily available over the Internet. While the product has a legitimate use as a VCR head cleaner, it is often illicitly marketed over the Internet as a means of getting a "rush" or "high" and for enhancing sexual pleasure. Neurologic symptoms have been reported after deliberate inhalational exposure to ethyl chloride, and 2 deaths have been associated with its use. An objective causality assessment using the Naranjo probability scale revealed a probable adverse drug event. CONCLUSIONS: Inhalants should be included in the differential diagnosis of patients presenting with acute mental status changes and neurologic impairment that resolve over less than one week.

Possible hazards of cryogen use with pulsed dye laser. A case report and summary.

BACKGROUND: Pulsed dye laser treatment of port-wine stains is safe and effective. However, the pain associated with this treatment is often difficult to tolerate, especially for children. A laser-coupled delivery system known as dynamic epidermal cooling has recently been developed to improve local anesthesia. OBJECTIVE: To report laser ignition of a commercially-available, hand-held cryogen spray used for local anesthesia, and describe possible mechanisms of the fire; to define the chemical characteristics of other skin coolants suitable and unsuitable for skin cooling with laser treatment. METHODS: Case report and literature review. CONCLUSIONS: Clinicians must be aware of the thermodynamic properties, potential for skin damage, cost and environmental consequences of commercially available cryogens before considering their use for topical anesthesia with laser surgery.

A risk-benefit assessment of topical percutaneous local anaesthetics in children.

Since its introduction, eutectic lidocaine-prilocaine cream ('EMLA')1 has been found to be an effective topical anaesthetic agent, with a high degree of efficacy, particularly for venepuncture and venous cannulation, and an impressive tolerability profile. Reports of adverse effects are remarkable for their rarity. The only problems that are likely to be encountered are oral ingestion of the cream (which may lead to anaesthesia of the oropharynx and possible toxicity secondary to rapid absorption of local anaesthetic from oral mucous membranes) and methaemoglobinaemia following repeated applications in neonates and infants. Analysis of the risks and benefits associated with its use comes down heavily in favour of the preparation. More recently, a preparation of tetracaine (amethocaine) has been marketed as a gel. Its advantages are a faster onset, and longer duration, of action than 'EMLA'. Although less widely used, it too has an impressive tolerability record. Concerns over the potential for anaphylactic type reactions due to its ester structure have not been realised in clinical practice. Of the other available preparations, lidocaine (lignocaine), applied iontophoretically, is unlikely to become popular because of the complexity of administration. A paste made of tetracaine, epinephrine (adrenaline) and cocaine (TAC) appears to be a far more toxic preparation on theoretical grounds, and this has been borne out in clinical practice; it is not as well tolerated as 'EMLA' or tetracaine gel. Ethyl chloride, although not a local anaesthetic, can safely provide cutaneous analgesia in children in circumstances when it is impractical to wait for a local anaesthetic preparation to take effect.

Allergic contact dermatitis from ethyl chloride and sensitization to dichlorodifluoromethane (CFC 12).

Despite the widespread use of ethyl chloride as a local anesthetic and chlorofluorocarbons as propellants in medical and cosmetic aerosols, contact allergy to these 2 gases is rare. In a 30-year-old woman, an unusual itchy dermatitis appeared at all skin sites where a medical aerosol containing ethyl chloride had been briefly applied. Subsequent re-exposure to the spray and patch tests revealed contact sensitization to ethyl chloride and dichlorodifluoromethane (CFC 12). Histologic and immunohistochemical examinations of the test reaction were consistent with a T-cell-mediated allergic reaction. The low incidence of contact allergy to ethyl chloride and chlorofluorocarbons may be due to the rapid evaporation of these volatile gases, thus preventing intense and prolonged contact with the skin and consequently contact sensitization. A modified patch test procedure using perforated plastic chambers to allow gas evaporation is necessary to test volatile agents.