A variety of neuromuscular diseases result in dystussia (disordered cough) or dysphagia (disordered swallow). Research in amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), stroke Alzheimer’s disease and Parkinson’s disease (PD) patients shows a high prevalence of a disorder of airway protection. A leading cause of death in these diseases is aspiration pneumonia – a consequence of dystussia and dysphagia.
Swallowing is a complex coordinated behavior, during which the body protects the airway by sealing the trachea to prevent aspiration into the airway. Swallowing may be induced by sensory feedback from the tongue, uvula, epiglottis, pharynx, esophagus, or other structures.
Coughing is a defensive reflex triggered in many instances by aspiration. There are typically three phases: inhalation, vocal fold adduction in which the trachea is sealed and pressure is built up in the lungs by contraction of abdominal muscles, and ballistic expiration including a rapid opening of the trachea and an explosive release of air generating high linear airflow velocities and shearing forces that remove material from the airway.
Both swallowing and coughing mechanisms are controlled by a network of neurons within the brainstem termed behavior control assemblies.
Department of Veterans Affairs researchers have developed a method and device to protect the airway and improve the health of patients – and in the case of certain diseases such as MS, ALS, ischemic or hemorrhagic stroke, PD and AD, – to reduce an incidence of aspiration pneumonia and subsequent death. The integrated system monitors and controls both coughing and swallowing.
In practice, electrodes are positioned upon the neck of the patient, the electrodes configured for both capturing electromyographic (EMG) information, and for transmitting a stimulating electrical signals to the body. A microphone is positioned upon the neck to capture audio information emanating from the body of the patient. Software analyzes the EMG and audio information to identify an attempted or needed cough or swallow, and causes the electrodes to apply an electrical stimulus to the neck of the patient to produce a more efficacious cough or swallow.
The device works on the premise that electrical stimulation of the superior laryngeal nerve (SLN), promotes either a swallow, cough, or both, dependent upon stimulation parameters. These events can be triggered by EMG measurements carried out by sensors or esophageal pressure, also measured by sensors. The device is triggered by behavior-specific markers in EMG, to provide behavior-specific programmed surface electrical stimulation routines to shape cough and swallow production.
The result of the stimulation is well timed and effective airway protection, including sealing of the trachea, coughing to remove contaminants within the airway, and swallowing to remove the contaminants from the pharynx. The device may further synchronize with respiratory patterns of the patient in real time, through EMG.
- Addresses common cause of death for patients with neuromuscular diseases
- Device is small and light weight, wearable and unobtrusive
- Businesses can commercialize the technology by licensing of U.S. Patents 9,042,992 and 9,375,568 from the VA
- License fees paid to the VA are negotiable
- TechLink navigates businesses through VA licensing at no charge