2007 HSR&D National Meeting Abstract
3085 — Comparison between Reflexive Cough after Water Swallow to Aerodynamic Measures of Voluntary Cough to Identify Patients with Stroke-Related Dysphagia
Smith Hammond CA (Durham VAMC; Duke University) , Ying J
(University of Cincinnati), Horner RD
(University of Cincinnati), Goldstein LB
(Duke University), Gray L
(Duke University), Gonzalez-Rothi L
(Gainesville VAMC; University of Florida), Bolser DC
(University of Florida)
Post-stroke dysphagia is associated with increased risk of pneumonia and mortality. Medical caregivers are known to rely on patients’ reaction to water swallows, i.e. presence of reflexive cough, to identify stroke patients at risk for aspiration. We hypothesized that the use of objective measures of voluntary cough would more accurately identify patients with post-stroke aspiration.
Ninety-six consecutive ischemic stroke patients underwent a bedside water swallow examination which included administration of water bolus, and aerodynamic and sound pressure level measures of voluntary cough, followed by videofluoroscopic (VSE) or endoscopic (FEES) swallowing studies (gold standard). Diagnostic accuracy of the reflexive cough after water swallow and objective voluntary cough measurement was assessed using sensitivity and specificity.
Reflexive cough after water swallow was present in 18 of the 33 (54.55%) aspirating patients and absent in 34 of the 63 (53.97%) non-aspirating patients. However, reflexive cough was absent in 3 aspirating patients (9.09%) but present in 8 non-aspirating patients (12.70%). Overall, 33 patients (34.88%) had inconclusive clinical signs on the water swallowing examination.
Low volume acceleration of voluntary cough (VA < 50 (L/s/s) correctly identified 30 of 33 aspirating patients, with a sensitivity of 91.67%. Of the 12 aspirating patients judged inconclusive using the clinical sign of reflexive cough, 11 were correctly identified using low VA. All 3 aspirating patients that were incorrectly identified due to absence of reflexive cough on the water swallow evaluation were correctly identified using the VA measure.
Among the 63 non-aspirating patients, 58 patients had a high VA (VA = 50 (L/s/s), leading to a specificity of 92.06%. Moreover, among the 21 non-aspirating patients whose clinical signs were inconclusive, the VA measure correctly identified 20. The VA measure also identified all 8 non-aspirating patients who were incorrectly diagnosed based on presence of reflexive cough on the water swallow test.
Aerodynamic measurement of voluntary cough is superior in identification of post-stroke risk for aspiration compared to reflexive cough after water swallow.
Improved assessment of aspiration risk that is achieved using non-invasive assessment of voluntary cough characteristics may reduce aspiration associated complications from stroke.