📊 Nitrous Oxide

Structure

FHF₃₃CCCOCH₂F

FDA Data Sheet

Basic Information

MAC: 2.11
MAC-BAR: 3
ED₉₅: 2.97 2
MAC-Awake: 0.8
Metabolism %: 2 - 51
Vapor Pressure: 1601

Blood/Gas: 0.691
Oil/Gas: 501

AgeMACMAC + 60%Nâ‚‚O
< 1 mo3.3%
1 - < 6 mo3.0%
6 mo - 3 yr2.8%2.0%
3 - 122.5%
252.6%1.4%
402.1%1,1%
601.7%0.9%
801.4%0.7%

Additional Info

  • MH Trigger
  • Inhalational anesthetic of choice for mask induction
  • Sinoatrial node discharge rate is slowed and conduction in the His-Purkinje system is prolonged (prolonged QT interval
  • ↑ RR, bronchodilation
  • ↓ TV, MV
  • Dose dependent depression of the ventilatory response to hypercarbia and hypoxia
  • ↓ ciliary movement and altered mucus characteristics
  • Dose dependent effect on skeletal muscle relaxation
  • Potentiates the action of neuromuscular blockers (greatest with myasthenia gravis)
  • In the presence of a dessicated COâ‚‚ absorber exothermic reaction with volatile anesthetics can lead to fire and/or carbon monoxide formation.
  • Sevoflurane breaks down in some COâ‚‚ absorbers to Compound A. For these COâ‚‚ absorbers the manufacturer recommends flow rates of 1-2 lpm for up to 2 MAC hours and 2 lpm thereafter.[^1] Compound A formed from this process has not been shown to be clinically significant. See Drägersorb Free for an example of an absorbent that does not form Compound A.
  • Most highly metabolized modern inhalational anesthetic. Metabolized into flouride ions with can be nephrotoxic although it has not been shown to be clinically significant in patients without kidney disease.[^1]
  • All MAC values can be decreased by co-administered agents (benzodiasepines, opioids, Alpha-2 agonists, etc.)

  1. Sevoflurane Data Sheet ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎

  2. Takita K, Yamane M, Morimoto Y, Kemmotsu O. The ED(95) of end-tidal sevoflurane concentration for the smooth exchange of the tracheal tube for a laryngeal mask airway is 2.97%. Can J Anaesth. 2003 Feb;50(2):184-8. doi: 10.1007/BF03017854. PMID: 12560312. ↩︎