A proposed standard for evaluating the thermal performance of pediatric dispersive electrodes

The authors have collected and analyzed 1,418 data points of current and duration of all electrosurgical unit activations from 23 surgical procedures on infants and children. The maximum radiofrequency current used was 550 mA and the duration was 4 sec. The maximum heating factor of 3.04 A2--sec was recorded at 225 mA for 60 sec. However, most data points lay between currents of 50-200 mA and durations of 1-5 sec. Using a three-dimensional computer model for a child thigh, the authors solved numerically first for the current density distribution, and then second the temperature elevation around pediatric dispersive electrodes. Derived curves showed that the maximum temperature under the electrode is proportional to the applied power and inversely proportional to the conducting area of the electrode. Analyzing results from pediatric current-duration experiments as well as computer simulation studies should assist in the design of new and improved pediatric dispersive electrodes. Finally, the authors propose a new standard for evaluating the thermal performance of pediatric dispersive electrodes.