Nitrous oxide sedation/analgesia in emergency medicine.

Nitrous oxide:oxygen mixtures are safe and effective sedative/analgesic agents for use in emergency medicine. They are suitable for prehospital care because of their safety, rapid onset, and short duration of action. The self-administered form of a 50:50 mixture is the most acceptable system, but other methods of administration should be investigated, particularly in the ED setting. While there are unresolved questions concerning the use of nitrous oxide as an anesthetic and analgesic agent, it is difficult to extrapolate many of the findings to the low-dose, patient-controlled 50:50 mixture used in emergency medicine. Use of the gas mixture in a variety of clinical settings has been associated with no major adverse occurrences, and experience continues to support its safety. Future possibilities for study include the use of the gas mixture in combination with other agents or TENS. No one drug can be considered a panacea for all painful states. Nitrous oxide:oxygen mixtures certainly do not meet all the criteria for the ideal analgesic. Those clinicians who seek a safe and effective sedative/analgesic for mild to moderate pain will be satisfied that we can now offer more to our patients in the early management of their problems.