| MAC | Blood:gas coefficient | Oil:gas coefficient | Molecular weight | Boiling point | SVP at 20ºC | Safe ppm |
| 6.6% | 0.4 | 29 | 168 | 23.5ºC | 89.2kPa | 50 |
- Pungent odour
Desflurane
Desflurane
- Desflurane is a fluorinated ethyl methyl ester
- It is a chiral molecule
- Slow to be introduced into practice due to difficulty in storing/preparation/administration
- Boiling point of 23.5ºC renders it highly volatile
- Uses the electronic Tec6 vaporiser that heats desflurane to 39ºC at 2atm
Metabolism
- 0.02% metabolised by CYP2E1 subfamily to trifluoroacetic acid
- Potential to produce toxic effects is minimal
- Greenhouse gas effect worse than isoflurane or sevoflurane
Respiratory
- Pungent odour causes coughing and breath holding, therefore is unsuitable for gas induction
- Reduces VT and minute ventilation, so there is a rise PaCO2
Cardiovascular
- Significant reduction in SVR and therefore mean arterial pressure
- Above MAC 1 (and certainly >1.5) produces tachycardia and hypertension
- No effect on splanchnic blood flow
- No sensitisation to catecholamines
Neurological
- Increases CBF and reduces CMRO2
- Potentiates muscle relaxation, including some relaxation of the uterus
- Can cause burst suppression on EEG
- Purportedly some analgesic properties