Aerodynamic characteristics of tracheostomy speaking valves

Pressure-flow characteristics were determined for four different one-way valves used for speech production in the patient who has had a tracheotomy. Each valve was tested at steady-state flow rates of 150, 250, 350, and 450 ml/sec in isolation and attached to a tracheostomy tube. Results indicated significant differences in resistance among the valves. The resistance of one valve was substantially greater than that of the normal upper airways. It is suggested that future research determine the clinical significance, if any, of these differences relative to speech and respiratory behaviors in tracheostomized patients.