Cough and Swallow Rehab Following Stroke

Summary

Stroke is the leading case of neurologic swallow dysfunction, or dysphagia. Post stroke dysphagia is associated with approximately 50% increase in the rate of pneumonia diagnoses; aspiration pneumonia is the most common respiratory complication in all stroke deaths, accounting for a three-fold increase in the 30-day post stroke death rate. The long-term goal of this systematic line of research is to decrease the morbidity, mortality, and health care costs associated with disordered airway protection following stroke.

The overall hypothesis central to this proposal is that the ability to protect the airway is dependent upon a continuum of multiple behaviors, including swallowing and cough. Safe, efficient swallowing prevents material from entering the larynx and lower airway, and effective cough ejects aspirate or mucus material. Currently, only one end of the continuum, swallowing, is rigorously assessed in stroke patients. However, ineffective or disordered cough is indicative of the inability to eject aspirate material or clear mucus and secretions from the lower airway. Ineffective clearance and subsequent accumulation of material in the lower airway increases the risk of chest infection. Hence, patients at the greatest risk for chest infection would not only have disordered swallowing (dysphagia) but also disordered cough (dystussia), meaning they are more likely to aspirate material and then cannot effectively eject the aspirate from the airway. There is a high likelihood that swallowing and cough are simultaneously disordered following stroke. To date, there is a treatment that targets both swallowing and cough function in stroke patients.

Expiratory muscle strength training (EMST) increases expiratory muscle strength (Baker et al., 2005) and there is evidence that supports its use to improve both swallow and cough functions in patients with Parkinson's disease (Troche et al., in press). This cross-system, device-driven approach to rehabilitating multiple contributors to airway protection deficits is highly desirable in the stroke population due to the likelihood of the co-occurrence of both swallow and cough disorders. To date, EMST has not been tested in stroke patients. We propose that by including cough in the screening, evaluation and treatment processes for disorders of airway protection, we will be able to better identify and treat patients most at risk for airway compromise and associated sequelae.

Conditions

• Ischemic Stroke

Interventions

BEHAVIORAL

Expiratory muscle strength training

Small hand held device that provides calibrated (cmH20) resistance to expiratory pressure. Once sufficient pressure is achieved (participant blowing out into the device) a valve is released, letting air flow through.

BEHAVIORAL

Placebo expiratory training

Device with the same look and feel as the active EMST, but which provides no resistance to airflow.

DRUG

Measures performed on all subjects

Capsaicin is a cough-inducing vapor that will be inhaled by participants to induce coughing. The airflow of the cough will be recorded and measures of compression phase duration, peak expiratory flow rate, and post-peak plateau phase will be made.

BEHAVIORAL

Pulmonary function test

Measures of forced vital capacity (FVC) and Forced expiratory volume in the 1st second (FEV1), and the ratio between the two measures (FEV1/FVC). Also included is the measure of maximum expiratory pressure. Airflow from the voluntary cough will also be recorded and measured using the spirometric system. These measures will be identical to those made on the capsaicin-induced cough.

RADIATION

Fluoroscopic swallow study

Images from the swallow study will be used to determine the modified barium swallow impairment profile (MBSImp) score, as well as the penetration-aspiration score (PA).

Sponsors & Collaborators

• American Heart Association

  collaborator OTHER

• University of Florida

  lead OTHER

Principal Investigators

• Karen W Hegland, PHD · University of Florida

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

50 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2011-01-31

Primary Completion

2015-04-30

Completion

2015-04-30

Countries

• United States

Study Locations