Steam sterilization chemical indicators are not adequate for monitoring real steam sterilization cycles.

Chemical indicators are commonly used in hospitals to monitor steam sterilization conditions, indicating that medical devices are safe to be used. The results are stored for future evidence in the event of an infection incident root cause analysis. This type of indicator is also becoming an option for cycle monitoring in pharmaceutical steam sterilizers, improving cycle control. They are constructed and tested according to published standards, but contradictory results between chemical indicators and cycle printouts have a critical impact on process control. We found that type 6 chemical indicators used in steam sterilizer cycles did not perform according to their intended use, showing an ″approved″ result in a ″failed″ cycle (a false positive). This study demonstrated that type 6 chemical indicator specifications are not adequate for monitoring steam sterilizers. A change in standards is therefore needed.

Cytotoxicity of cannulas for ophthalmic surgery after cleaning and sterilization: evaluation of the use of enzymatic detergent to remove residual ophthalmic viscosurgical device material.

PURPOSE: To evaluate the cytotoxicity of reusable cannulas for ophthalmic surgery after the cannulas were filled with an ophthalmic viscosurgical device (OVD) and cleaned with an enzymatic detergent. SETTING: Microbiological Testing Laboratory, Department of Medical-Surgical Nursing, University of São Paulo School of Nursing, and Cell Culture Section, Adolfo Lutz Institute, São Paulo, Brazil. DESIGN: Experimental study. METHODS: The sample consisted of 30 reusable 25-gauge injection cannulas, 20.0 mm in length, whose lumens were filled with an OVD solution for 50 minutes. The following steps were used to process the cannulas: (1) presoaking, (2) washing the lumen using a high-pressure water jet, (3) backwashing with enzymatic detergent in ultrasonic cleaner, (4) preliminary rinsing with tap water, (5) final rinsing with sterile distilled water, (6) drying with compressed filtered air, (7) wrapping in surgical-grade paper, and (8) steam sterilization at 134°C for 4 minutes. The cannulas were then tested for cytotoxicity according to the United States Pharmacopeia 32. RESULTS: The cleaning protocol used in this study removed residues of OVD solution and enzymatic detergent as shown by the lack of cytotoxicity of all sample extracts. CONCLUSION: This cleaning protocol has the potential to minimize the occurrence of toxic anterior segment syndrome associated with residues of OVD solutions and enzymatic detergents. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.