250 wrapped load woes

[sonny1388]

Do any of you have problems with 250 loads passing BI tests? It is recommended that a BI be run with every cycle change (i.e. 270 is normal, change to 250 for special instruments). I just learned this, and have begun implementing it, but come out with positive BI's more often than not. I called 3M and they said that it works if you bump the sterilize time to 40mins instead of 30, but this is not what is recommended by the manufacturers of most of the items we run (they recommend 30mins). I changed the times anyways, and are still getting about 60% positive BI results.

Any ideas, suggestions?

[autoclave1]

Question---are you using rapid read out or 24/48 hour incubation BI's?
If you are using rapid read, have you tried using 24/48 hour and compared the results? If you are using 24/48 hour, did you send the BI's to the lab for further analysis?

[Chuck Hughes]

Sonny,

The 3M RRBI test pack was not FDA cleared for a standard 30 min gravity cycle at 250F/121C. It requires a 40 min cycle, therefore, the reason for their recommendation for you to extend your standard cycle. It's very important to make sure the BI test pack you choose is compatible with the cycle(s) your sterilizer mfg and device mfg were cleared to. I'd be happy to speak with you offline regarding our test pack and others cleared for use in 30min gravity 250F cycles.

Chuck Hughes
General Manager/Educator
SPSmedical Supply Corp.
1-800-722-1529 www.spsmedical.com

[sonny1388]

We are using the rapid reads. I have not been sending them to the lab, just rewrapping and resterilizing. We do not have this problem with any of our prevac cycles, which I just realized might point to a problem in the evac phase.

Chuck- Thank you for the info, and drop me a line sometime. We are currently using your 24hr BI for the steris and are very happy. I would love to get a BI that is good to use on a 30min cycle since that is what our instruments are supposed to be ran at. E-mail @ lawrenceb@ivinsonhospital.org

[autoclave1]

Sonny,
The evacuation phase has nothing to do with a 250 Gravity cycle. It is called a Gravity cycle for just that reason. Steam is used to push the air out from the chamber via the purge or conditioning part of the cycle, then the steam traps take over. A 250 cycle typically runs at a pressure of 18-22 PSI, while a pre-vac cycle typically runs at 28-32 psi. In order for the conditioning phase of a pre-vac cycle to operate properly, it purges between 26 PSI an vacuum set points. A 250 cycle never reaches 26 PSI. The exception to this rule would be a labroatory or research facility.

Mike Huff
H & H SERVICES 1-800-314-5509

[sonny1388]

Exactly, what you are referring to as the 'conditioning cycle' I was referring to as the evac cycle, meaning the phase where the steam is pushed in and the air is pushed out. If there isn't enough pressure from the steam to push all of the air out, or the steam traps aren't working correctly, I thought that might have an impact on the BI. However, according to the printouts, all of the parameters are still being met. Thanks for the info!