Nitrous oxide toxicity
Background
- Nitrous oxide toxicity is often associated with inhalation of whipped cream or small nitrous oxide cannisters (whippets)
- Nitrous is much more soluble in blood and will quickly diffuse from the blood to a closed space
- Beyond the gaseous effects nitrous oxide mainly disrupts B12 by oxidizing the cobalt ion which irreversibly inhibits methionine synthase[1]
- Epidemiology
- Rates of nitrous oxide misuse vary significantly by country and are generally higher in Europe and the United States.
- The World Drug Report found use (i.e. at least once within last 12 months) doubled globally between 2015 to 2021, from 10% to 20%.[2]
- Most nitrous oxide misuse is sporadic and without health consequences. This and its ease of availability may lead users to erroneously view it as risk-free.
- Nitrous oxide use is undetectable by standard drug screens, making it crucial to obtain a thorough history.[3]
Clinical Features
Differential Diagnosis
Acute complications
- Pneumothorax (induced by forceful inhalation or high-pressure tank siphoning)
- Tympanic membrane rupture
- Tracheal trauma
- Air emboli
- Thrombotic events (rare, typically in subacute toxicity from homocysteine elevation)
Chronic complications
- Bone marrow suppression (from long term exposure)
Evaluation
Workup
Diagnosis
Management
Disposition
See Also
External Links
References
- ↑ Nunn J. Clinical aspects of the interaction between nitrous oxide and vitamin B12. British Journal of Anaesthesia. 1987; 59:3-13
- ↑ United Nations Office on Drugs and Crime. World Drug Report 2021. 2021. [1]
- ↑ Agarwal P, et al. Recreational nitrous oxide-induced subacute combined degeneration of the spinal cord. Cureus. 2021;13(11):e19377. [2]