A Surgical Instrument Cover for the Prevention of Thermal Injuries During Laparoscopic Operations

Accidental thermal injuries are infrequent, nonetheless, dangerous complications in laparoscopic surgery. Burns are produced because of direct contact, lack of instrument insulation and capacitive coupling. Biological fluids on the surface of laparoscopic instruments behave as electric conductors on the sheath and may be responsible for accidental thermal injuries. Our hypothesis is that using an insulator device may prevent those injuries.

After evaluating different materials for dielectric properties, costs, and temperature increase tolerance, we selected polytetrafluoroethylene (PTFE) to develop a sleeve that works as an electrical insulator when applied on the sheath of laparoscopic instruments. Efficacy of this PTFE cover in reducing conduction of electricity was tested on both reusable and disposable laparoscopic instruments.

Electric conduction of the laparoscopic instrument sheaths was tested using an ex vivo model that reproduces the abdominal environment in basal conditions and in presence of blood. Electric conduction of laparoscopic instruments was measured before and after the placement of the PTFE cover. We measured a significant difference in electric resistance on the sheath's surface without and with blood, revealing a weak electrical conduction: infinity versus a median value of 251.11 Mohm, respectively.

This ex vivo study demonstrated that a PTFE sleeve may reduce electricity conduction of laparoscopic instruments. A pilot in vivo study is planned to test its safety and efficacy.