Hyoid bone and laryngeal movement dependent upon presence of a tracheotomy tube

The aim of this prospective, consecutive study was to investigate the biomechanical effects, if any, of the presence of a tracheotomy tube and tube cuff status, tube capping status, and aspiration status on movement of the hyoid bone and larynx during normal swallowing. Seven adult patients (5 male, 2 female) with an age range of 46-82 years (mean = 63 years) participated. Criteria for inclusion were no history of cancer of or surgery to the head and neck (except tracheotomy), normal cognition, normal swallowing, and ability to tolerate decannulation. Digital videofluoroscopic swallowing studies were performed at 30 frames/s and with each patient seated upright in the lateral plane. Variables evaluated included maximum hyoid bone displacement and larynx-to-hyoid bone approximation under three randomized conditions: tracheotomy tube in and open with a 5-cc air-inflated cuff; tracheotomy tube in and capped with deflated cuff; and tracheotomy tube out (decannulated). Differences between maximum hyoid bone displacement and larynx-to-hyoid approximation (cm) based on presence/absence of a tracheotomy tube, tube cuff status, and tube capping status were analyzed with the Student's t test. Reliability testing with a Pearson product moment correlation was performed on 21% of the data. No significant differences (p > 0.05) were found for both maximum hyoid bone displacement and larynx-to-hyoid bone approximation during normal swallowing based on tracheotomy tube presence, tube cuff status, or tube capping status. Intraobserver reliability for combined measurements of maximum hyoid displacement and larynx-to-hyoid approximation was r = 0.97 and interobserver reliability for the absence of aspiration was 100%. For the first time with objective data it was shown that the presence of a tracheotomy tube did not significantly alter two important components of normal pharyngeal swallow biomechanics, i.e., hyoid bone movement and laryngeal excursion. The hypothesis that a tracheotomy tube tethers the larynx thereby preventing hyoid bone and laryngeal movement during normal swallowing is not supported.