The Effect of Radiofrequency Energy on Ambient Fluid Temperature in an Enclosed Compartment: An in Vitro Model of the Subacromial Space

Abstract

Background Radiofrequency (RF) devices are widely used in arthroscopic shoulder surgery for tissue ablation and other effects. They have heating effect during tissue application. It is known that chondrocyte death occurs with temperatures above 45 °C. The present study aimed to investigate the effect of various factors on the heating effect of RF probes in a controlled in vitro model. Methods A perspex model was used, in which volume, flow, outflow position, duration of RF probe use and inflow temperature could be closely controlled. Results Temperature rises in the bathing fluid sufficient to cause cell death were seen. The temperature rise was most noticeable when there was no fluid flow through the compartment, at smaller fluid volumes, if the fluid inflow temperature is elevated, and if the outflow is distant from the RF device. Of note, 30 seconds of use in a volume of 20 mL with no flow led to temperatures above 50 °C. Discussion Most of the factors affecting temperature rises using RF devices are directly under the surgeon's control. Further work is needed in this area to define the potential clinical effects of the use of these devices.