Assessment of Dystussia in Traumatic Brain Injury
Condition: TBI; Brain Injury
MeSH terms: Brain Injuries; Brain Injuries, Traumatic; Wounds and Injuries
Study type: Interventional
Phase: Early Phase 1

Summary: 
      The purpose of this research study is to evaluate coughing in people who have had a brain
      injury. It is hypothesized that individuals who have sustained a brain injury will
      demonstrate differences in cough waveform and respiratory measures compared to individuals
      who have not sustained a brain injury.
    

Detailed description: 
      Recovery of people with mild, moderate, or severe swallowing, speech, hearing, and
      cognitive-communication impairments is best facilitated by a team of multidisciplinary
      specialists. Symptoms associated with traumatic brain injury (TBI) include disordered
      swallowing (dysphagia), ataxia and, frequently, but not inevitably, dysarthria or disorder of
      speech. Airway compromise also exists in the form of impaired cough, or dystussia. In view of
      the frequency of oral intake problems in individuals with TBI and the presence of weakened
      cough, or absence of cough, along with the added challenge of the cognitive-communicative
      problems, further studies are needed to increase our understanding of the degree of
      disordered airway protection. From this work appropriate intervention strategies can be
      designed along with an understanding of the compensations that may be used to assist with
      improving swallow and airway safety, oral intake and management.

      Informed Consent Process:

      Investigators working with subjects with TBI, and who are also aware of this study, will have
      the ability to provide potential participants with a business card containing only the name
      of the study coordinator (Dr. Erin Silverman) as well as her email and telephone numbers. The
      individual participants will be responsible for contacting Dr. Silverman if they wish to
      participate. Additional participants will be recruited via face to face methods and by the
      previously IRB-approved study flyer at local brain injury support groups and Shands
      Rehabilitation Hospital.The staff member consenting (Dr. Silverman) has completed University
      of Florida training on HIPAA and privacy issues. Subjects do not have to give an immediate
      response about enrolling and may freely discuss the study with people of their choice before
      making a decision. Capacity to consent will be decided by the consenting staff member (Dr.
      Silverman). The study will be explained to the subject, any questions answered, and a written
      and signed consent completed along with a HIPAA authorization. Written consent will be
      obtained prior to collection of any health history or study data. Once written informed
      consent is obtained, Dr. Silverman will conduct an extensive interview in order to insure the
      subject meets all required inclusionary/exclusionary criteria.

      Neuropsychological Testing: The MOCA (Montreal Cognitive Assessment) will be administered by
      Dr. Silverman, on each participant, upon entry into the study.

      Measures of TBI severity: Multiple studies have correlated severity of TBI upon initial
      admission related to the TBI with swallowing function. The Glasgow Coma Scale (GCS) and
      Rancho Los Amigos Scale (RLAS) are commonly administered upon admission of TBI patients. When
      available (availability may vary depending on the hospital at initial admission) we will
      record the GCS and/or RLAS scores from admission. As well, the investigators will administer
      the RLAS upon enrollment in the study. These measures will be incorporated into our
      statistical model to better understand the heterogeneity of cognitive impairment on swallow
      and cough function.

      Cough and respiratory measures: Pulmonary status screening measures: The forced expired
      volume in the first second (FEV1) of a forced vital capacity (FVC) exhalation are measures
      used to screen pulmonary function (American Thoracic Society). Spirometry is used to derive
      FVC, FEV1 and the ratio FEV1/FVC measures (Spirovision 3+m, Futuremed). Alternatively, if the
      subject is unable to perform the cognitive voluntary spirometric task, upper airway
      respiratory resistance will be measured with impulse oscillometry (lOS, Jaeger Instruments).

      Maximum Respiratory Pressures: Maximum inspiratory and expiratory pressures are an indirect
      measure of inspiratory and expiratory muscle strength, respectively. The ability to generate
      high expiratory airflows is essential to producing high expiratory airflow, and subsequently
      cough production and will be measured at the initial assessment in all studies.

      Cough: The participant will be instrumented for the measurement of the respiratory airflow
      pattern during spontaneous breathing, voluntary cough and reflex capsaicin induced cough. A
      facemask with a pneumotachograph will be used to record the airflow changes associated with
      spontaneous breathing and cough. The mouth airflow signal will be digitized and recorded on a
      desktop computer (Chart, ADinstruments, Inc). Inspiratory and expiratory muscle EMG will be
      recorded to provide a neuromuscular motor assessment of cough strength. The computer signals
      will be analyzed to determine inspiratory breath phase, expiratory breath phase, inspiratory
      cough phase, cough compression phase, and expiratory cough phase. Because it has been
      reported that brain injury differentially affects the neuromuscular motor pattern of
      voluntary and reflex elicited coughs, it is essential to elicit coughs with both peripheral
      afferent stimulation (capsaicin; reflexive cough) and voluntary induced cough in these TBI
      participants.

      Capsaicin administration: After the participant is instrumented with the facemask, he/she
      will be seated comfortably in a chair in front of an airflow fume hood. The airflow fume hood
      prevents exposure of the participant and experimenter to the nebulized solution except when
      the participant inhales for the capsaicin challenge. Participants will inspire deeply through
      the nebulizer (containing the capsaicin or a vehicle solution) coupled to the facemask and
      pneumotachograph. The outflow nebulizer gas will be passed through an isopropyl alcohol
      solution to remove capsaicin from the air vented into the fume hood. Cough threshold and
      sensitivity will be determined using our established randomized block presentation method of
      graded capsaicin concentrations (0-2001-JM). The investigators have an FDA IND # 76866 for
      the use of capsaicin in the study of cough motor pattern. This will take 10-15 minutes to
      complete.

      Design and Procedures: This project will address the Specific Aim over a 1-year time period.
      Our Specific Aim will focus on characterizing the mechanical features of swallow and cough
      motor function in subjects with TBI and the swallow and cough reconfiguration of respiratory
      pattern. Our Specific Aim will allow us to determine the relationship between TBI and both
      swallow and cough dysfunction.

      Study Protocol: Subjects with a medical history of TBI will be recruited from community TBI
      support groups and through face to face recruitment procedures. Once informed consent has
      been obtained, relevant medical history will be reviewed, and the participants will complete
      screening procedures to determine inclusionary/exclusionary criteria. If inclusionary and
      exclusionary criteria are met, participants will complete the following tests:

        -  MIP and MEP measurement

        -  Reflex and voluntary cough assessments

      Timeframe: This is a one-time visit study. Therefore, participants will be followed only on
      the day they present for study procedures. There will be no follow up beyond this day.
    

Intervention name(s): Neuropsychological Testing and Measures of TBI severity; Respiratory measures; Capsaicin cough sensitivity testing
Intervention type(s): Behavioral; Behavioral; Drug
Intervention description(s): A brief cognitive assessment will be given to each participant when he or she presents for this project.; We will collect measures of cough airflow and breathing strength.; Subjects will inhale a saline vapor mixed with various concentrations of capsaicin powder in order to determine how sensitive his or her cough response is.
Other intervention name(s): Cough reflex testing
Intervention MeSH terms: Capsaicin
Intervention model: Single Group Assignment
Masking: None (Open Label)
Keywords: respiratory; cough