Does blood on "dirty" instruments interfere with the effectiveness of sterilization technologies?

Biofilms on medical instruments and surfaces: Do they interfere with instrument reprocessing and surface disinfection

BACKGROUND

Biofilms are surface-attached communities of bacteria embedded in an extracellular matrix. This matrix shields the resident cells from desiccation, chemical perturbation, invasion by other bacteria, and confers reduced susceptibility to antibiotics and disinfectants. There is growing evidence that biofilms on medical instruments (especially endoscopes) and environmental surfaces interfere with cleaning and disinfection.

METHODS

The English literature on the impact of biofilms in medicine was reviewed with a focus on the impact of biofilms on reusable semicritical medical instruments and hospital environmental surfaces.

RESULTS

Biofilms are frequently present on hospital environmental surfaces and reusable medical equipment. Important health care...associated pathogens that readily form biofilms on environmental surfaces include Staphylococcus aureus, Pseudomonas aeruginosa, and Candida auris. Evidence has demonstrated that biofilms interfere with cleaning and disinfection.

DISCUSSION

New technologies such as ..úself-disinfecting..Ñ surfaces or continuous room disinfection systems may reduce or disrupt biofilm formation and are under study to reduce the impact of the contaminated surface environment on health care...associated infections.

CONCLUSIONS

Future research is urgently needed to develop methods to reduce or eliminate biofilms from forming on implantable medical devices, reusable medical equipment, and hospital surfaces.

Risk of disease transmission to patients from "contaminated" surgical instruments and immediate use steam sterilization

BACKGROUND

There are several sources of pathogens that cause surgical site infections (SSI) to include the patients endogenous microflora and exogenous sources (e.g., air, surfaces, staff, surgical equipment).

METHODS

We searched the published English literature (Google, Google Scholar, PubMed) for articles on reprocessing surgical instruments, effectiveness of sterilization methods, microbial load on surgical instruments, frequency of "contaminated" instruments, and the infection risk associated with "contaminated" surgical instruments and immediate use steam sterilization.

RESULTS

There is substantial redundancy in instrument reprocessing to include: even if a patient was exposed to a "contaminated" instrument, the decontamination and sterilization process would have removed and/or inactivated the contaminating pathogens due to the exceptional effectiveness of the manual and mechanical cleaning (i.e., washer-disinfector) and the remarkable robustness of sterilization technology; and the low-level of microorganisms on surgical instruments after use and before cleaning.

CONCLUSIONS

A critical review of the literature suggests that the risk of acquiring an SSI from instruments used in surgery is essentially zero if the sterilization cycle is validated.