Role of sensation in swallowing function

Objectives: Sensation in the oral cavity and laryngopharynx has long been b elieved to be crucial for normal swallowing. One illustration of this belie f has been intense interest in reconstruction after cancer resection using sensate tissue transfer as a means of improving swallowing function. A cont rarian view is that mucosal sensation, by itself, is, in fact, relatively u nimportant to swallowing function. Study Design: A prospective study was de signed to test the hypothesis that normal swallow function can occur with a nesthesia of the upper aerodigestive tract mucosa, Methods: Baseline (sensa te) swallowing function of 13 healthy adults was assessed via video endosco pic swallow studies (VESS). Each subject was then topically anesthetized wi th lidocaine applied to the oral cavity, oropharynx, hypopharynx, and laryn x. Swallowing was then reassessed via VESS and compared to the base-line ex amination to look for differences in function. Results: There was little di fference in swallowing ability between sensate and anesthetized states, eve n though all the subjects felt that their swallowing had been profoundly di srupted after Lidocaine was applied. The main difference was a small increa se in the time from food administration to swallowing, A few experienced tr ace aspiration, which was instantly eliminated on subsequent swallows with simple coaching. Conclusion: Normal swallowing can occur spontaneously or w ith simple coaching even with complete anesthesia of the upper aerodigestiv e tract mucosa, Current beliefs about the value of sensate free flaps and t he importance of sensation in swallowing in general may need refinement.