Ferrell M, Wolf C E, Ellenbogen K A, Wood M A, Clemo H F, Gilligan D M
Department of Internal Medicine, Medical College of Virginia and Virginia Commonwealth University, Richmond, USA.
Am J Cardiol. 1997 Dec 15;80(12):1558-61. doi: 10.1016/s0002-9149(97)00785-6.
Reuse of electrophysiology catheters is an important cost-saving option for many laboratories. However, to be reused safely, catheters must undergo resterilization with ethylene oxide (EtO). Residual EtO levels on resterilized catheters may be high and could pose a risk to patients. Resterilized diagnostic electrophysiology catheters were tested for residual EtO using headspace gas chromatography after both a standard resterilization with an aeration process and after a resterilization process that incorporated a detoxification period. The Food and Drug Administration's maximum permissible level of EtO for implantable products, 25 parts per million (ppm), was used as the cutoff for acceptable catheter residuals. At day 2 after standard resterilization, the residual level of EtO on catheters was high at 41 +/- 6 ppm. However, these levels decreased with shelf time, decreasing to 26 +/- 3 ppm by day 7 and to 14 +/- 2 ppm by day 14 after sterilization, at which time all catheters were <25 ppm (p <0.001). Detoxification periods of 6, 12, and 15 hours were tested and 15 hours was found to be optimal. After 15 hours of detoxification, residual EtO was 19 +/- 1 ppm by day 2 and all catheters were <25 ppm. In summary, electrophysiology catheters that have undergone resterilization have residual EtO levels that are twice the Food and Drug Administration's limit for implantable products. Residual EtO levels may be substantially reduced either by allowing a 14-day waiting period after resterilization or by incorporating a detoxification period immediately after EtO exposure.
对许多实验室来说，重复使用电生理导管是一项重要的成本节约措施。然而，为了安全地重复使用，导管必须用环氧乙烷（EtO）进行再次灭菌。再次灭菌后的导管上环氧乙烷残留水平可能很高，会对患者构成风险。对再次灭菌后的诊断性电生理导管，在采用通气过程的标准再次灭菌后以及采用包含解毒期的再次灭菌过程后，使用顶空气相色谱法检测环氧乙烷残留量。美国食品药品监督管理局规定的可植入产品环氧乙烷最大允许水平为百万分之25（ppm），以此作为可接受的导管残留量临界值。在标准再次灭菌后第2天，导管上环氧乙烷残留水平很高，为41±6 ppm。然而，这些水平会随着储存时间下降，灭菌后第7天降至26±3 ppm，第14天降至14±2 ppm，此时所有导管的残留量均<25 ppm（p<0.001）。对6小时、12小时和15小时的解毒期进行了测试，发现15小时为最佳时长。解毒15小时后，第2天环氧乙烷残留量为19±1 ppm，所有导管残留量均<25 ppm。总之，经过再次灭菌的电生理导管环氧乙烷残留水平是美国食品药品监督管理局规定的可植入产品限量的两倍。通过在再次灭菌后等待14天或在环氧乙烷暴露后立即设置解毒期，环氧乙烷残留水平可大幅降低。
