Silver nitrate: histological effects of cautery on epithelial surfaces with varying contact times.

Silver nitrate is used extensively in rhinological practice for the treatment of recurrent epistaxis. There are currently no recommendations in the literature regarding the optimum application time of this chemical for effective treatment. We assessed the histological effects of silver nitrate on mucosal tissue at varying contact times and made recommendations based on our findings. Silver nitrate was applied at predetermined contact times to tonsillar mucosa, immediately before tonsillectomy in subjects undergoing routine surgery. The cauterized areas were subsequently analysed histologically. The depth of tissue penetration by the silver nitrate was measured. The means for 5, 10 and 20 s were 0.44, 0.30 and 0.38, respectively, P = 0.3. Overall, there was no deeper penetration of the tissues with contact times over 5 s. We conclude that it is not necessary to apply silver nitrate for greater than 5 s to achieve maximal tissue penetration.