How To Maintain And Test Your Veterinary Anesthesia Machine To Ensure It's Functioning Correctly Before Performing Surgery

28 April 2018
 Categories: , Blog


To keep your patients safe, it's important to frequently test your veterinary anesthesia machine. Leaks in the system can result in an inadequate amount of oxygen or anesthetic reaching the patient, which can be dangerous. You'll also need to ensure that your machine is correctly removing carbon dioxide from the exhaled air before it's recirculated. This procedure should be done before every operation — it doesn't take long to test your machine. Here's what you need to do before every operation to test your veterinary anesthesia machine and make sure it's functioning correctly.

Check Your Canisters, Soda Lime, and Scavenger System

First, you'll need to check your oxygen canister to make sure that it has an adequate amount of oxygen. Depending on the type of oxygen canister you are using, this is often as easy as making sure the pressure gauge on the canister isn't in the red zone. Otherwise, you may have to turn the nozzle on and use a pressure gauge to make sure the oxygen is flowing at the correct pressure. Consult the manual for your oxygen canister for the optimal pressure reading. If you're using nitrous oxide, you'll have to check that canister as well.

Two other components you need to check are the soda lime and the charcoal canisters in your veterinary anesthesia machine. The soda lime filters carbon dioxide gas from the recirculated air, preventing the animal under anesthesia from accidentally inhaling a high level of carbon dioxide. It needs to be replaced periodically — follow the instructions from the soda lime manufacturer and track how often you are using your veterinary anesthesia machine. Typically, you'll need to empty and refill the soda lime canister every 12 hours of use. Ensure that you're tracking how often your veterinary anesthesia machine is used so that you're replacing your soda lime on schedule.

Your veterinary anesthesia machine may have charcoal canisters in its scavenger system. This filters anesthetic agent from the air and prevents it from leaking into the operating room. When the charcoal absorbs anesthetic, it becomes heavier. You'll have to weigh your charcoal canisters at the start of the day to determine if they need to be replaced. Other scavenger systems simply exhaust air outside of your veterinary clinic — all you need to do to maintain these systems is to make sure it's not leaking.

Detect and Fix Any Leaks in Your Veterinary Anesthesia Machine

Next, you need to test the entire system for leaks. You should do this before every procedure. Connect the oxygen canister to your veterinary anesthesia machine, close the pop-off valve to stop air from exiting through the scavenger system, attach a reservoir bag to your machine and place your thumb over the hose that administers anesthesia. This closes the entire system and doesn't allow air to escape from the machine. Push the oxygen flush button to begin filling the reservoir bag and keep an eye on the manometer on the valve that leads to the bag. Fill the bag until the manometer reads 20 cm and then stop. If the pressure reading begins to fall, it means that you have a leak somewhere in your anesthesia machine that needs to be found before you proceed with surgery.

An easy way to pinpoint leaks is to cover any leak-prone areas with soapy water. Air leaks cause the soap to form bubbles, which allows you to easily spot where the leak is occurring. You'll have to apply it to all your hoses, nozzles and O-rings. Once you've found the leak, replace the faulty part and test for leaks in your machine again to make sure you've caught them all. Don't forget to wash off all the soap when you're done, as it leaves a sticky residue. An alternative to soapy water is liquid leak detector, which forms bubbles more readily than soapy water and is capable of finding very small leaks.

Testing your veterinary anesthesia machine before every operation reduces the risk that something goes wrong during the surgery due to the machine malfunctioning. An additional maintenance task that you need to perform is to have the vaporizers in the machine serviced at least once a year by a professional technician. A leaky seal or cracked vaporizer can cause too much anesthetic to leak into the anesthetic hose, endangering your animals. If you haven't had your vaporizer units serviced, call a technician to have yours examined as soon as possible. To learn more, contact a company like Keebovet