The thickness of the tracheoesophageal party wall may limit the choice of prosthetic devices, because some styles are not manufactured in extremely short or long lengths. For patients with a narrowed esophagus, a duckbill style prosthesis may impinge on the posterior esophageal wall. This may prevent the prosthesis valve from opening, resulting in poor vocal quality, or alternately, it may cause the prosthesis to remain in the open position, resulting in leakage through the prosthesis. When all requirements have been met to maintain the patency of the puncture tract and ensure the viability of the tracheoesophageal tissue, the clinician should consider the aerodynamic characteristics that will promote a satisfactory vocal quality with a minimum of effort. The aerodynamic specifications of each device are available from the manufacturer so that accurate comparisons can be made.
Some general guidelines follow.
The duckbill type devices typically have a higher resistance to airflow than most of the hinged or ball valve devices, resulting in a voice of lower volume. However, the increased resistance may be beneficial for patients who experience excessive gas that is due to the inhalation of air through a prosthesis of lower resistance during quiet respiration. If there are any concerns regarding the patient s ability to care for the device, an extended wear prosthesis should be selected. These prostheses are typically less likely to dislodge accidentally due to the design of the esophageal retention collar and they require infrequent changes by the speech-language pathologist or physician, reducing the patient s responsibility for maintaining the device. When there is limited availability of medical support services in the patient s community, an extended wear device that can only be replaced by a physician or speech-language pathologist may represent a poor choice of prosthesis.