Scavenging System  To reduce exposure to waste anesthetic gases  Can be active or passive scavenging system Active Scavenging System  Connected to a vacuum that sucks the waste gases out of the machine…concerns?  Runs them through a drop down line, through pipes in the ceiling, and outside Passive Scavenging System  Uses pressure in circuit to expel gases from the machine, out through a hole in the wall  Must be room adjacent to the outside

Scavenging System  Activated charcoal cartridge  Cheaper than installing a scavenger  Is mobile  Easy to use with little maintenance Example: F/air canister  Must be discarded after 12 hours of use or a gain of 50 grams  Down side: do not absorb nitrous oxide

Leak Testing  Performed before every anesthesia to check the system for leaks  The last thing you do on your anesthetic machine *Hint: this will also tell you if your machine is hooked up correctly  If running nitrous oxide, you must do a high pressure leak test  This is done by: turning on the nitrous tank and then turning it off  do not flush the lines to get the pressure out  check in 1 hour and make sure gauge reading the same

Leak Testing – Low Pressure Test  Used when oxygen is your carrier gas  Steps: close pop-off valve AND cover end of rebreathing tube with something  Turn on flow meter to 2 L/min and let oxygen fill reservoir bag  Once full, turn down the O 2 to 0.2 L/min  Gently squeeze the bag and listen/feel for leaks  If none, maintain a full bag for 30 seconds at 30 cm H2O If the bag doesn’t hold pressure (remain full), you have a leak!

Oxygen Flow Rates  Chamber Induction: 1-3 L/min for < 10 kg 3-5 L/min for > 10 kg  Mask Induction: 5 L/min  Rebreathing system: ml/kg/min Note: this may be increased if you are inducing, changing anesthetic depth, or recovering patient