is it true that if the manufacturer recommends a 4 minute prevac cycle it is OK to run that item for 18 minutes? There is a debate going on because of guidelines for total knee & total hip instrumentation. We have received guidelines from these manufacturers that their instruments need to be sterilized for 18 minutes. My question is: Does it harm instruments (drills, saws, cords) to run in an 18 minute cycle when the manufacturer recommends that they be run in a 4 minute cycle?

Hi Jamie,

You need to determine the maximum permitted time/temperture for the instruments from the manufacturer then ensure thay are compatible with your sterilizer.

The (most common) standard temperature/times for sterilizing equipment are 121-124 for minimum 15 minutes and 134-137 for minimum 3minutes (European Pharmacopia). Normally times and temperatures used outwith these time/temp need validating.

Validation of the sterilizer and your instrumentation would confirm the suitability and if the instruments can withstand the additional time you mentioned.

Hope this helps

Gary Philp
Validation Manager
C&M Scientific Ltd
Scotland

Hi Jamie

Answer to your 2nd question:
Sterilization is a compromise between destruction of micro-organism and destruction of the goods you sterilize.
4 factors are aging significally materials: temperature, pressure, rate of temp. change and rate of pressure change.
Metal is more stable to aging than plastic cord. If 10 years ago, no (almost) plastic could withstand 134 C, today, you can find many plastics which does.
There are "non metal" materials that withstand 134/3 rather than 121/15. But the instrument manufacturer shall confirm it.

1st question:
The International Health Organisation recognize Sterilization exposure temperature / time of 134C/3min; 126/10; 121/15 as default conditions. This will assure survival of less than 1 micro-organism of milion.
Now, consider the current difficulties: packaging, load configuration, air removal, steam penetration etc., and validate it (later on, challenge the load) and you will conclude to ad 1 min. (30%!)
Emphasis shall be drawn to pre-sterilization actions: Cleaning-Washing-Disinfection

miki