Comparison of thermal coagulation profiles for bipolar forceps with different cooling mechanisms in a porcine model of spinal surgery

BACKGROUND: Coagulation accomplished using bipolar forceps is common in neurosurgery. Control of thermal spread from the forceps tips into surrounding neural tissues is a persistent concern, as neural tissues are especially vulnerable to heat injury. The purpose of our investigation was to compare the efficacy of cooling mechanisms for four different bipolar forceps and to understand thermal spread when coagulating vessels on the spinal cord. METHODS: Immediately following euthanasia, the dura mater of an ex vivo porcine model was opened to expose vessels on the spinal cord for coagulation. Temperature profiles were measured at generator power of 25 W and at fixed 5-second activation times. The bipolar forceps used in this study included regular stainless steel, titanium, heat-pipe embedded, and SILVERGlide forceps. Temperature was measured by micro-thermistor at the midpoint between the bipolar tips, and 1 and 2 mm away from the midpoint along the centerline. Statistical analysis was performed to evaluate temperature differences. RESULTS: Temperature profiles indicated that heat-pipe embedded forceps create the least amount of temperature increase and the highest normalized temperature decreasing slope after activation. The decreasing slope of SILVERGlide forceps is slightly higher than that of regular stainless steel forceps. CONCLUSIONS: Bipolar forceps incorporating either heat-pipe embedded technology or SILVERGlide coating can effectively limit excessive thermal spread, thus decreasing potential injury to adjacent tissues when compared with standard stainless steel and titanium bipolar forceps. Of the two, heat-pipe embedded technology appeared safest, having better cooling efficiency at higher temperature.