In vivo measurements of an improved tracheostoma valve based on inhalation

An improved, inhalation-based tracheostoma valve (TSV) was designed to facilitate finger-free tracheoesophageal speech. In contrast to existing models, the TSV closes by means of strong inhalation (instead of exhalation) to reach the "speaking position." Air is inhaled through a small 1-way valve that allows unlimited phonation time. The device can be deliberately changed to the "breathing position" by a fast expiration. Experimental setups were used to measure in vitro and in vivo the performance of the inhalation TSV. In patients, the inhalation TSV was compared with existing TSVs on the following parameters: air volume used to close the TSVs, speaking time of the TSVs, and total air volume during exhalation through the TSVs. The inhalation TSV functions well in physiological ranges, is optimally adjustable, and is an improvement over existing devices. It makes continuous speech possible and saves as much as 22% of the total exhalation volume for speaking, in contrast to existing TSVs.