Re-Sterilisation of Single-Use Telemetric Devices

Implantable telemetric transponders for contactless measurement of physiological parameters are often used in animal-based research. After explantation, single-use devices cannot be re-implanted because of non-validated functionality and necessary re-sterilisation. This is disadvantageous because the battery life would enable a second implantation cycle in another animal. To save costs and time taken for the manufacturer's refurbishing process, we validated and implemented a re-sterilisation protocol for single-use transponders using hydrogen peroxide gas. The described protocol was established with models, i.e., for large (n = 7) and small (n = 3) animals, of telemetric device from 2 different manufacturers (Data Science International and EMKA). All transponders, prepared according to the protocol, were previously implanted subcutaneously in the flank of pigs or rats for a duration of 21 days. Our investigations demonstrate that disinfection only is not sufficient against bacterial contamination and that sterility can only be achieved by additional gas sterilisation with hydrogen peroxide. Furthermore, re-implantation of the re-sterilised transponders into pigs caused neither undesired tissue reactions along the transponder nor impairment of the measured values when compared to the first implantation and after necropsy in 4 cases. We were able to demonstrate that, using our protocol, re-implantation of reprocessed single-use telemetric devices can be performed without compromising transponder quality.