Maintenance for veterinary anesthetic machines is often overlooked.  Being proactive with your maintenance can avoid problems, is to institute a regular maintenance schedule for all machines and equipment. Below you will find technical advice and maintenance tips that will extend the life of your equipment. A well-maintained device will also reduce gas consumption and the level of pollution in the room which will keep employees safe.

Weekly Anesthesia Machine Maintenance Checklist:

  • Step 1 – Connect the circuit to be verified to the fresh gas outlet of the anesthesia machine.
  • Step 2 – Close the patient’s circuit outlet with a plug or your thumb.
  • Step 3 – Open the flowmeter to approximately .2 liters.
  • Step 4 – Close the pop-off valve.
  • Step 5 – Depress the oxygen flush button and hold until the pressure on the pressure gauge indicates approximately 20 PSI.
  • Step 6 – Check the pressure gauge. The pressure must not drop (but it can increase). If the pressure drops, replace the patient circuit and the bag and try again.
  • Step 7 – Open the pop-off valve before using the anesthesia machine again.

If you encounter an excessive leak, we recommend repeating the pressure test and spray the unit components with Windex ®. Bubbles in the Windex will appear and reveal the source of the leak. Once the leak is identified, dispose of the defective item to avoid it being reused by error. At the end of each day, it is recommended that you close the oxygen tank and fill up the anesthetic agent vaporizer.

Changing the Soda Lime

Soda-lime has a variable life span depending on the gas flow and the size of the animals. A simple rule is to replace the soda-lime every 14 hours of use of the absorber. We suggest that you identify, with a tag or another method, the date the replacement was made. The following are signs of overused granules: Hard, brittle granules and granules color change to purple (remember the granules will change the color back to white after several hours of non-use). For another indication that the soda-lime needs to be changed, put on some gloves and hold a small amount between your pressed fingers and squeeze slightly – soda lime in good condition will easily turn into a fine dust.

Cleaning & Disinfecting

Masks, breathing hoses, reservoir bags, and ET tubes should be sanitized after each use to avoid the spread of bacterial/fungal contamination. This apparatus can be cleaned with disinfecting soap using a soft brush, then soak it in diluted chlorhexidine (18mls of chlorhexidine for every 32 ounces of water). Bear in mind, cleaning agents such as glutaraldehyde solutions or ethylene oxide gas sterilization should not be used because they have the potential to cause tracheal necrosis.

Decreasing Exposure & How to Clean Veterinary Endotracheal Tubes

The following daily tips will lower your staff’s risk of exposure to anesthetic gases:

  1. Always attach breathing circuits prior to turning on the vaporizer.
  2. Make sure all tubing is completely sealed. Check for leaks by suppling a positive pressure, breath up to 15 – 20mmHg. If stable and positive pressure cannot be attained, it is likely that air is escaping from the patient’s mouth, or the reservoir bag decompresses of air after steady positive pressure is reached then additional air should be added to the cuff. (Use caution to prevent over-inflation of the cuff which can cause ischemia.)
  3. Whenever removing a patient of the anesthesia machine, make sure the oxygen and vaporizer are off.
  4. It is best practice to utilize a scavenging system. This will eliminate any inhalants while flushing out the breathing circuit for patients that need to remain on oxygen while in recovery.  This will remove any leftover of anesthetic gases that might be in the system.
  5. Minimize the use of a masked or closed container inhalant anesthetic induction of patients.
  6. If there is no scavenge system, make sure to at least exhaust thru an activated charcoal canister.
  7. Lower the fresh-gas flow rate as much as you can, while still allowing an adequate delivery of anesthetic to the patient. Higher than needed flow rates will just waste gas.

Annual Maintenance of Your Anesthesia Machine

It is recommended to have the preventive maintenance done by a Medicanix service technician once a year. We will perform in-depth pressure tests and check the calibration of the unit. If the unit is out of calibration, we will take it with us to be calibrated at our repair shop and then provide you with a report on the performance of your vaporizer and on the anesthesia machine. If components are failing or leaking, we can procure and replace those parts on your behalf.