Biochemical and microbial contamination of surgical devices: a quantitative analysis

Reusable devices are required to be safety processed prior to patient use, including cleaning and disinfection and sterilization. In developing and testing cleaning processes, it is important to understand the levels of soils typically present on devices after surgical use. Previous soil investigations have focused on microbial contamination levels; less is known about biochemical contamination. In this study, microbial and biochemical contamination on a range of surgical instrumentation after patient use were investigated. Analysis included bacteria levels, total organic carbon, protein, and hemoglobin. The highest levels of soil contamination were caused by protein, in contrast with bacteria levels being a minor component of instrument soiling. This study provides a better understanding of the microbial and biochemical levels of soils that are typically present in used surgical devices. These levels can be used to develop artificial test soils for testing cleaning efficacy under laboratory conditions and to further evaluate patient risks from inadequate cleaning.