Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

Cleaning Failure to adequately clean instrument results in higher bioburden, protein load, and salt concentration. These will decrease sterilization efficacy. Bioburden The natural bioburden of used surgical devices is 10 to 10 organisms (primarily vegetative bacteria), which is substantially below the 10-10 spores used with biological indicators. Pathogen type Spore-forming organisms are most resistant to sterilization and are the test organisms required for FDA clearance. However, the contaminating microflora on used surgical instruments consists mainly of vegetative bacteria. Protein Residual protein decreases efficacy of sterilization. However, cleaning appears to rapidly remove protein load. Salt Residual salt decreases efficacy of sterilization more than does protein load. However, cleaning appears to rapidly remove salt load. Biofilm accumulation Biofilm accumulation reduces efficacy of sterilization by impairing exposure of the sterilant to the microbial cell. Lumen length Increasing lumen length impairs sterilant penetration. May require forced flow through lumen to achieve sterilization. Lumen diameter Decreasing lumen diameter impairs sterilant penetration. May require forced flow through lumen to achieve sterilization. Restricted flow Sterilant must come into contact with microorganisms. Device designs that prevent or inhibit this contact (e.g., sharp bends, blind lumens) will decrease sterilization efficacy. Device design and