When an induction chamber is connected to your in-house scavenging system anesthetic gas enters the chamber and empties from the chamber at the same time. This is highly inefficient. It can take up to 5 minutes to fill a chamber with the right concentration of anesthetic gas to anesthetize an animal.
When an induction chamber is connected to the Induction Chamber Evacuation System, the chamber reaches the right concentration much faster because the scavenging system is passive (filtering WAG into an activated charcoal canister during filling) and because incoming gas hits a baffle that causes the gas to circulate inside the chamber while filling.
Then, before opening, scavenging becomes active and waste anesthetic gas is quickly removed before opening to remove the animal.
When cats bite
It's not a question of if, but when an animal handler will be bitten by a cat.
How much vapor is derived from 1 ml of a volatile anesthetic?
How much anesthetic is administered to an animal when a "small amount" is put on a cotton ball and placed near the animal's nose?
"The amount of volatile agent vapour deriving from 1 ml of fluid agent...
The Induction Chamber Evacuation makes the press!
The Induction Chamber Evacuation System is mentioned in Veterinary Anesthetic Monitoring and Equipment, published by Wiley, edited by Kristen G. Cooley and Rebecca A. Johnson. The book will be released October, 2018.
Delayed induction time
Using traditional methods of filling an induction chamber while connected to an in-house (active) scavenging system; it can take as long as 8 minutes for the top portion of an induction chamber to reach 3% isoflurane, resulting in a delayed and stressful induction.