Safety and efficacy of cold atmospheric plasma for the sterilization of a Pasteurella multocida–contaminated subcutaneously implanted foreign body in rabbits

Abstract

To determine whether a stainless steel implant sterilized with a novel cold atmospheric plasma sterilization (CAPS) device adversely affects local tissues in rabbits and whether CAPS was as effective as steam sterilization with an autoclave to inactivate Pasteurella multocida. 31 healthy New Zealand White rabbits. Steam-autoclaved stainless steel implants inoculated with P multocida underwent a second steam autoclave sterilization (AIA) or CAPS (AICAPS). One AIA implant and 3 AICAPS implants were randomly placed subcutaneously at 4 sites in 21 rabbits (84 implants). These rabbits were monitored daily for 5 days for evidence of systemic illness and local tissue reactions at the implantation sites and then euthanized. Samples were taken from each implant site for bacterial culture and histologic examination. Cultures of samples obtained from all sites were negative for bacterial growth. No significant difference was observed in mean skin thickness or erythema between AIA and AICAPS implant sites on any observed day. Also, individual histologic grades for the epidermis, dermis, subcutis, and muscle and total histologic grade were not significantly different between AIA and AICAPS implant sites. Cold atmospheric plasma sterilization was noninferior to steam sterilization of P multocida-contaminated stainless steel implants in the rabbits in the present study. However, studies of the efficacy of CAPS for inactivation of other important bacteria are needed.