Safety evaluation of single-use medical devices after submission to simulated reutilization cycles

Pyrogenic and toxic reactions, especially in immunologically compromised patients, are among the risks associated with reuse of single-use medical devices (SUDs) with recurrent damaged surfaces. These drawbacks have raised serious doubts about the true benefits of the reprocessing practice. Taking into consideration prolonged patients' stay in hospitals due to adverse reactions provoked by recycled SUDs, the safety of these reprocessed materials was evaluated. The reprocessing cycles were simulated after intentional contamination of selected test material such as intravenous catheters, 3-way stopcocks, and tracheostomy tubes with Bacillus subtilis var. niger ATCC 9372 spores (10(7) CFU/unit). The repeated reprocessing cycles consisted of subsequent wash with enzymatic detergent followed by drying and sterilization with ethylene oxide-CFC (12 + 88), 600 mg/L at 55 degrees C, relative humidity 60%, for 3 h. After each reprocessing cycle, specimen samples were evaluated by pour plate microbial counts, direct and indirect inoculation sterility tests, cytotoxicity evaluation, and scanning electron microscopy (SEM). Microbial counts as high as 10(3) CFU were evident even after the 10th reprocessing cycle, besides scratched and damaged surfaces observed by SEM. Risk-benefit viewpoints are discussed.