. When used properly, with meticulous patient monitoring, it is safe and effective. In my practice, I have used it for procedures as simple as a skin biopsy. While we have excellent topical numbing options for pain control, nitrous oxide works well as an anxiolytic and can help calm the patient who is nervous or has a fear of needles.
Dr. Lily Talakoub
Nitrous oxide is a tasteless gas synthesized and released by cells. Inhalational nitrous oxide is absorbed from the lungs and diffuses into plasma, where it acts on the central nervous system as an anxiolytic and analgesic by blocking the NMDA receptor. It has a quick onset of action and short duration, is easily titrated, and has a low side effect profile.
Initially used to provide pain relief during labor in the late 1800s, nitrous oxide is now rarely used in the United States as inhalational analgesia during surgery or labor; however, use in dentistry and pediatrics is common. In a recent review of PubMed and Cochrane databases by Brotzman et al., eight studies on the use of nitrous oxide in dermatology were identified. Studies reported favorable safety and efficacy of nitrous oxide in providing analgesia during dermatologic procedures, which included facial rejuvenation, hair transplantation, and pediatric procedures. Several other studies also discussed the use of nitrous oxide in combination with tumescent anesthesia for venous ablation and liposuction. All adverse effects were limited to the time of inhalation and included euphoria, laughter, nausea, dizziness, and vertigo. There are no studies reviewing the risk of nitrous oxide used during CO2 resurfacing procedures.
In five of the eight studies, vital signs and oxygen saturation were recorded during the period of inhalation. Almost all patients maintained adequate oxygen saturation and vitals also remained stable in these five studies, except for a slight increase in systolic and diastolic arterial pressure after ulcer debridement. In four of the eight studies, a 50% nitrous oxide/50% oxygen mixture delivered through an on-demand valve activated by a patient’s inspired breaths was used to minimize the risk of oversedation and to prevent hypoxia.
Dr. Naissan O. Wesley
Contraindications for using nitrous oxide are pregnancy (in patients, health care providers, and assistants). Relative contraindications include nasal obstruction, chronic obstructive pulmonary disease, active cystic fibrosis, recent tympanic membrane surgery, and claustrophobia. According to the National Institute for Occupational Safety and Health, occupational exposure to nitrous oxide can lead to adverse effects that include reduced fertility and spontaneous abortion, as well as neurologic, renal, and hepatic diseases. The consensus of the majority of the studies in the PubMed/Cochrane review is that nitrous oxide provided a significant reduction in pain during dermatologic procedures, with mild and transient adverse effects. The effects dissipated quickly and thus patients could drive themselves home. But studies remain limited, and more well designed, randomized clinical trials are needed to provide clinical guidelines, safety monitoring protocols, and evidence for the use of nitrous oxide in dermatology. In my opinion, when more data are available, it will become one of the mainstays of analgesia in dermatologic procedures, particularly for pediatric, Mohs, and facial rejuvenation procedures.
Dr. Talakoub Dr. Wesley and are cocontributors to this column. Dr. Talakoub is in private practice in McLean, Va. Dr. Wesley practices dermatology in Beverly Hills, Calif. This month’s column is by Dr. Talakoub. Write to them at dermnews@mdedge.com. They had no relevant disclosures.
Sources
Brotzman EA et al. Dermatol Surg. 2018 May;44(5):661-9.
“Controlling Exposures to Nitrous Oxide During Anesthetic Administration,” National Institute for Occupational Safety and Health (https://www.cdc.gov/niosh/docs/94-100/default.html).