Ethylene Oxide Sterilisation

Ethylene oxide sterilisation has become more important to the veterinary profession as effective implementation of hygienic measures is advised to prevent and contain the transmission of nosocomial infections to animals and humans both within veterinary settings and in the community(FECAVA working group on hygiene 2010).

Whereas most veterinary practises have access to an autoclave for routine sterilisation of surgical instruments ,swabs and drapes etc it is more problematic when sterility is required for heat sensitive items such as endoscopes.clothing ,implants.catheters,electric or battery operated tools etc.

If you are considering the use of anprolene the following information may be of benefit.

1.When used as directed it is very safe.

2.Training is recommended and is generally provided by the supplier at installation.

3 At sea level ethylene oxide is a liquid below 51 degrees F.Above 51 degrees F ,EtO begins to boil and converts into a gas.It does not become an effective sterilant until 68 degrees F.So the room where your anprolene steriliser is installed must be capable of maintaining 68 degrees F for the duration of the sterilising cycle

4 Relative humidity should be at least 35% in the room where item preparation and sterilisation take place.

To prepare items for sterilisation four basic steps should always be followed.

1. Disassemble.

Items containing removable parts such as syringes must be taken apart before washing.Instruments which contain batteries should be taken apart and the batteries removed and wrapped separately to protect against a spark occurring .

2.Wash

Items must be washed surgically clean prior to sterilisation.For cleaning we recommend using a detergent.

3. Dry

Two accepted ways to dry any item prior to sterilisation with Anprolene

A. Towel Drying

B.Air Drying

Heat or hot air should never be used  for drying as it will dehydrate or dessiccate bacteria spores making them more resistant to the ethylene oxide gas.Items should be dried thoroughly as any water left on items may react with gas. 

4.Wrap

The following types of wrapping material are recommended for use with Anprolene

A. Andersen seal and peel.

B.Cloth ,like CSR wrap has an estimated sterile shelf life of 30 days

C.Self seal pouches

D.Tyvek paper pouches

Exposure indicators  which change colour when exposed to ethylene oxide are available.

The usual Anprolene sterilisation cycle is 12 hours plus a 2 hour purge cycle.When sterilising lengths of tubing 3 feet or longer or a full load of gas absorbant items it may be necessary to increase the cycle time to 24 hours.

Items made of gas absorbent material must be aerated at a minimum room temperature of 68 degrees F for at least 24 hours prior to use. 

For supplies or advice please contact me pfxtkavanagh@gmail.com