Surface wear and accumulation of microscopic residues on ageing stainless-steel surgical instruments may impact patient safety.

BACKGROUND: The stainless-steel surfaces of heat-sterilizable, reusable surgical instruments are subject to usage and age-related wearing through their lifetime. Soil tends to accumulate in poorly accessible areas and microscopic grooves and cavities present on these surfaces, which are often more difficult to decontaminate. AIM: To examine the surface of various stainless-steel reusable instruments for signs of wear and its potential impact on the efficacy of standard reprocessing using highly sensitive epifluorescence microscopy. METHODS: Using both bright light epi-microscopy and specific fluorescent dyes, we looked for any surface modifications and possible correlation with soil retention on decommissioned instruments in the laboratory and on instruments in current use in a large sterile services department which adopted the same technology for direct, in situ routine surveillance of reprocessed instruments in accordance with national guidelines. FINDINGS: Surfaces on all ageing instruments examined presented microscopic abrasions, scratch marks and sometimes cracks with loose microscopic metal fragments potentially liable to cause harm. Damaged surface areas and voluntary markings on instruments appeared as "hot spots" for protein retention. CONCLUSION: The unavoidable usage-related wearing of reusable surgical instruments contributes to facilitate soil adsorption and impact on the efficacy of standard reprocessing. Considering that metallic fragments and some residues may lead to adverse events and possibly iatrogenic infections, end users would benefit from more readily available, sensitive quality control standards and tools to survey reusable instrument surfaces, thus helping decision making regarding in house handling procedures, instruments reusability or potential refurbishment/replacement to reduce any potential risk to patients.