Desflurane inhalation agent

Desflurane inhalation agent was synthesized by Dr Terell (1992) among 600 compounds. Desflurane inhalation agent is a halogenated ether. It has the lowest blood/gas solubility coefficient amongst all inhalation agents, including N20, hence quick induction and recovery. Et does not contain chlorine or bromine, so it does not deplete ozone layer in the atmosphere.

Physical Properties: Desflurane inhalation agent is a clear fluid, in amber bottles, stable (no preservative), pungent odour, non-flammable, not broken down by soda lime, baralyme, light, metal or alkali.

Desflurane inhalation agent has a bp of 22.8°C just above room temperature (i.e., of operation theatres), SVP at 20°C 664 mm Hg (88.3 kPa), this means Desflurane inhalation agent cannot be used in conventional vapourizers but needs a special vapourizer at a constant temperature (by heater) and pressure 1500 mm Hg (200 kPa) and then mixed with a carrier gas.

The blood/gas solubility coefficient is 0.42, the lowest of all inhalation agents except xenon. So, induction and recovery are quick. Solubility in rubber and plastic is least amongst all agents. The MAC of desflurane varies from 4.5% to 7.25% (average 6.5%) decreasing with extremes of age and with N2O.

Uptake and distribution of Desflurane inhalation agent : Having the lowest blood/gas solubility it has the fastest induction and recovery.

The inspiratory/alveolar ratio (FJ:FA) is higher (0.9) than that for sevoflurane (0.85) or isoflurane (0.78) or halothane (0.58). The distribution is in a 5-compartment model as with other agents—lungs, blood, VRG organs, muscle, fat around VRG and finally peripheral fat.

 

One Response

  1. Richelle Leed August 10, 2011

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