| MAC | Blood:gas coefficient | Oil:gas coefficient | Molecular weight | Boiling point | SVP at 20ºC | Safe ppm |
| 1.7% | 1.9 | 98 | 184.5 | 56.5ºC | 23.3kPa | 50 |
- Non-irritant
Enflurane
Enflurane
- Enflurane is a halogenated ethyl methyl ester
- It has a chiral carbon and is a structural isomer of isoflurane
- It has largely been superseded by other agents
Metabolism
- 2% metabolised by CYP2E1 subfamily to inorganic and organic fluorides
- Fluoride ions are nephrotoxic therefore to be avoided in renal failure
Respiratory
- Significant reduction in VT and therefore increases PaCO2
Cardiovascular
- Causes:
- Reduced myocardial contractility and therefore cardiac output
- Reduced SVR
- Reflex tachycardia suggests carotid sinus baroreceptor reflex is preserved
- Net effect is a reduction in mean arterial pressure
- Some reduction in splanchnic blood flow
- Does sensitise myocardium to catecholamines
Neurological
- Increases CBF and reduces CMRO2
- At high concentrations causes 3Hz spike & wave activity on EEG, consistent with grand mal activity
- Significant potentiation of muscle relaxation and some uterine relaxation
- Purportedly some analgesic properties
- The -CHF2 group may react with dry soda lime or baralyme to produce carbon monoxide
- If a circle system is left with dry gas circulating, subsequent use of enflurane may cause carbon dioxide release