Nitrous oxide is a drug of dependence - do not leave the delivery unit accessible to the patient. Cylinders should be stored in a secure area. If the patient is hypovolaemic, closer observation is necessary as the patient may rapidly lose consciousness. If there is any risk of vomiting, the patient should be in the lateral position. Entonox is flammable.
Caution is necessary if metal cutting equipment is used at an accident site.
The relative proportions of gases issuing from cylinders are affected by temperatures below -7oC when the contents separate. In cold climates they must not be stored in vehicles or outdoors. Warming involves immersing in warm water not exceeding 37oC for not less than 5 minutes. When entonox is used regularly in a closed environment, it is desirable to duct the exhaled gases to the outside atmosphere. If consciousness is lost, the mask falls away and the demand valve does not function.