The development of a commercially available aspirometer.
T. Chau, M. Casas, C.M. Steele, G. Berall, D. Kenny (research and development team); M. Bennett, D. Shukaris, J. McIntyre, A. Sochaniwskyj, S. Carkner (commercialization team)
Funder: Health Technology Exchange

The inability to swallow safely (dysphagia) is a common sequel to a variety of neurologic disorders and contributes significantly to mortality (Murray, Carrau & Eibling, 1999). According to the Heart and Stroke Foundation of Canada, there are approximately 200,000-300,000 Canadians living with the consequences of stroke, with approximately 40,000-50,000 new stroke events documented each year. With 40 per cent of stroke patients presenting with swallowing disorders, this condition affects up to 20,000 new individuals per year.

Aspiration is a serious swallowing abnormality, defined as the entry of foreign material (food, liquid, saliva, etc.) into the airway below the level of the vocal folds (Rosenbek et al., 1996). Aspiration has been linked to the development of pneumonia (Marik, 2001); as many as 20 per cent of stroke patients are reported to die within the first year from aspiration pneumonia (Schmidt, Smirnov & Ryabova, 1988). Pneumonia is the leading cause of acute care hospitalization (Muder, 1998) and the primary cause of death (Muder, 1998) in many diseases found amongst long-term care residents.

The Aspirometer is a small, portable, wearable device that has been developed to non-invasively and safely monitors swallowing. The device is intended to assist caregivers and clinicians in accurately identifying and indicating (warning) that aspiration is occurring. Product testing to date has shown that the Aspirometer is able to detect aspiration in children with dysphagia due to cerebral palsy, through analysis of acoustic and vibratory information collected at the surface of the neck during swallowing. Sensitivity of the device to aspiration has been shown to be superior to clinical detection of aspiration by expert clinicians (Chau et al., 2005).

The purpose of the current study is to conduct further validation tests using the Aspirometer to measure swallowing events in an adult population as part of the further commercial development of the Aspirometer. Specifically, we will measure the sensitivity and specificity of the Aspirometer to aspiration and other swallowing abnormalities in adults with acquired neurogenic dysphagia, who are undergoing assessment of their swallowing at the Toronto Rehabilitation Institute. The sensitivity of the Aspirometer to swallowing abnormalities will be measured in comparison to blinded ratings of the current industry gold standard for instrumental swallowing assessment (videofluoroscopy).