The Effect of Diathermy Power Settings on Oral Cavity Mucosal Contraction: A Rat Model.

OBJECTIVES/HYPOTHESIS The effects of different electrocautery power settings on mucosal contraction and margin status in the oral cavity have not been well established. The aim of this study was to examine how different levels of electrocautery energy outputs affect oral mucosal tissue margins. STUDY DESIGN Animal model. METHODS A model of 23 adult rats was used (two specimens per rat). After anesthetizing the animals, a 6-mm biopsy punch marked the resection margin on the buccal mucosa (one per cheek). The specimens were excised by means of three energy levels, a cold knife, and monopolar diathermy that was set on either 20 W or 30 W cut modes. The specimens were evaluated for extent of contraction. RESULTS A total of 45 samples were obtained and measured, including 15 specimens in the cold-knife group, 15 specimens in the 20 W group, and 15 specimens in the 30 W group. The median diameters of the specimens after resection were 4.5 mm for the cold-knife group (interquartile range [IQR] = 4.0-5.0), 3.5 mm for the 20 W group (IQR = 3.5-4.0), and 2.8 mm for the 30 W group (IQR = 2.5-3.0). Specimen contraction was 25.0%, 41.7%, and 53.3%, respectively. The difference in shrinkage between each pair was statistically significant: cold knife versus 20 W, P = .001; cold knife versus 30 W, P < .0001; and 20 W versus 30 W, P < .001. CONCLUSIONS Diathermy power settings result in a significant difference of mucosal tissue contraction, with higher outputs resulting in a narrower mucosal margin. It is imperative that the surgical team take into consideration the diathermy settings during initial resection planning. Laryngoscope, 2020.