Desflurane vaporizer basic question

[Turtlez]

Desflurane is heated to 39 degrees to replace latent heat of vaporization so that the transition from liquid to gas phases is more uniform? It's pressurized to 2atm to increase the boiling point so that it doesn't all vaporize too quickly? Does the vapor pressure increase when heated to 39 degrees and decrease when pressurized at 2atm? So is the gas concentration = vapor pressure of desflurane (at 39 degrees and 2atm) divided by (760mmHg x 2)?

Can someone please explain this physics stuff?

---

Members don't see this ad.

 

[Iso4ane]

Have you been reading Hall? Because, if so I know what question you are referring to and the answer key is poorly worded/formatted.

But, vapor pressure is a innate/intensive property of the substance that can be dependent on other factors like temperature. The problem with desflurane, as you kinda touched on is that it evaporates too easily, when something evaporates it cools down (think about you sweating on a hot summer day), as such the temperature of desflurane fluctuates altering its vapor pressure (which would lead to unreliable and variable output.) So if you heat it to a specific and constant temperature the vapor pressure will remain constant. However, at 39C the vapor pressure of des is 1300mmHg, which on its own is almost 2 atm. And your last part was correct, the gas conc should be vapor pressure/overall pressure.

 

[Aether2000]

This is the exact problem we had with ether in the Vernitrol vaporizers we used back in the dark ages. One had to compensate for the temperature, therefore the Vernitrol had a temperature measurement and you had to use a series of nomographs in order to determine the actual output of the vaporizer.

 

[Iso4ane]

And technically. temperature is a problem for iso and sevo, but that is solved in a different manner.

 

[drmwvr]

This is the exact problem we had with ether in the Vernitrol vaporizers we used back in the dark ages. One had to compensate for the temperature, therefore the Vernitrol had a temperature measurement and you had to use a series of nomographs in order to determine the actual output of the vaporizer.

I still have my Ohio "wheel"