seeing the forest through the wheeze: laryngeal involvement in
TRANSCRIPT
Seeing the Forest Through
the Wheeze:
Laryngeal Involvement in
Episodes of Dyspnea
Marc Haxer, M.A., CCC-Sp
Departments of Speech-Language Pathology and Otolaryngology/Head and Neck Surgery
University of Michigan Health System
Introduction
• Goals/Objectives – Become familiar with upper versus lower
airway etiologies for dyspnea
– Become able to differentially diagnose upper airway involvement in dyspnea
– Become familiar with chronic cough, involuntary vocal fold closure, laryngospasm, adductory laryngeal breathing dystonia and irritable larynx syndrome as they relate to compromised respiration
Larynx
• Cartilaginous tube – Connects inferiorly to respiratory system
• Trachea, lungs
– Connects superiorly to vocal tract • Pharynx, oropharynx, nasopharynx
• Anatomic orientation important – Highlights interactive relationship between vocal
subsystems • Pulmonary mechanism
• Laryngeal valve
• Supraglottic vocal tract resonator
Larynx
• Complex arrangement of muscles, mucus membranes, and other connective tissue – Soft tissues responsible for airway preservation
– Cartilage housing serves as columnar protective shield for laryngeal valve
• Muscles and cartilages provide three levels of “folds” – Serve as sphincters which provide communicative and
vegetative functions
– Angles of closure multidimensional (valve in horizontal and vertical planes)
Larynx
• Upper rim of larynx formed by aryepiglottic folds
– Fibrous membrane extending from epiglottis to arytenoid towers
– Thus serves as lateral boundary of larynx
– Epiglottic inversion posteriorly/inferiorly over laryngeal vestibule results in separation of larynx from pharynx and serves as most superior level of airway protection
Larynx
• Second sphincter formed by ventricular folds – Not normally active during phonation – Can become hyperfunctional during episodes of
increased vocal effort/extreme vegetative closure – Directly superior to ventricle/true vocal folds – Form double layer of medial closure w/TVFs if needed – Principle function is to increase intrathoracic pressure
by blocking exhalatory airflow from lungs – Compress tightly during sneezing/coughing, lifting,
emesis, childbirth, defecation – Also provide medial level of airway protection during
swallows
Larynx
• Most inferiorly are true vocal folds
– Provide vibrating source for phonation
– Also close tightly for nonspeech and vegetative tasks
• Thus, larynx and vocal folds function as variable valve
– Modulate airflow through VFs during phonation
– Close off trachea/lungs to prevent soiling of airway during swallows
– Provide resistance to increased abdominal pressure during effortful activities
Neurologic Supply
• Cranial nerve X innervates larynx peripherally
– Vagus = “wanderer”
– Innervates sites from skull to abdomen
• Innervates larynx through two important branches
– Superior laryngeal nerve (SLN)
– Recurrent laryngeal nerve (RLN)
Neurologic Supply
• Superior laryngeal nerve
– Branches off vagus near nodose ganglia in neck
– Course alongside carotid artery
– Forms internal/external branches
• Internal branch inserts through thyrohyoid membrane superior to VFs and provides all sensory information to larynx
• External branch is motor nerve to cricothyroid (CT) muscle
Neurologic Supply
• Recurrent laryngeal nerve – Extends to thorax
– Forms long loop under heart before coursing superiorly under thyroid gland and into larynx
– Different on right/left sides of body • L RLN courses under aorta
• R RLN course under subclavian artery
– Nerves (especially left) susceptible to injury
– Supplies all sensory information to area below VFs and all motor innervation to PCA, TA, LCA, and IA muscles
Where/What’s the Problem?
• Upper airway issue?
• Lower airway issue?
• Problem w/inhalation?
• Problem w/exhalation?
• Problem w/both?
• Acute versus chronic issue?
• Episodes same/different w/regard to presentation?
• Episodes same/different w/regard to severity?
Upper Airway Issues that can Compromise Respiration
• Unilateral vocal fold motion impairment (abductory) • Bilateral vocal fold motion impairment (abductory) • Reinke’s edema • Laryngeal papilloma • Laryngeal carcinoma • Vocal Fold Granuloma • Laryngospasm • Involuntary vocal fold closure • Cough • Adductory Laryngeal Breathing Dystonia • Acute infection (eg croup, laryngitis, epiglottitis) • Allergies • Laryngomalacia • Tracheomalacia/Stenosis • Foreign body in airway • Extrinsic/intrinsic airway compression by tumor inferior to glottis
Lower Airway Issues that can Compromise Respiration
• Asthma
• COPD
• Emphysema
• Restrictive Airway Disease
• Lung Cancer
• Interstitial lung disease
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Chronic sinusitis/URI
– Cough/throat clear
• Can cause trauma to laryngeal tissues
– Antihistamines
• Dry secretions
• Resultant dehydration of VFs
– Anti-cough medications
• Drying agents
• Contribute to VF dehydration
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Asthma
• Chronic obstructive pulmonary disease
• Emphysema
• Lung CA – Above can be direct/indirect cause of laryngeal
problems • Vocal fold tissue abuse
• Poor breath support
• Vocal fold dryness secondary to medication use
• VF paresis/paralysis
• Cough
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Allergies
– Congestion/edema of VFs
– VF dehydration
– VF tissue trauma
• cough/throat clear
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Laryngopharyngeal reflux disease – Is GERD that affects pharynx/larynx
– Occult chronic reflux is etiologic factor in high percentage of patients w/laryngologic complaints
– Reflux involves multiple anatomic sites • LES
• Entire esophagus
• UES
• Larynx/pharynx/oral cavity
• Trachea
• Lungs
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Laryngopharyngeal reflux disease – Symptoms
• Chronic hoarseness • Voice fatigue • Cough • Chronic throat clearing • Globus sensation • Sensation of choking • Edema • Ulceration/granulation of laryngeal mucosa • Hyperkeratosis • Carcinoma of larynx
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Laryngopharyngeal reflux disease – LPRD best managed via multidisciplinary team
• Otolaryngologist
• Internist/PCP
• Gastroenterologist
• Allergist
• Pulmonologist
• Speech Pathologist
• Nutritionist
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Laryngopharyngeal reflux disease
– Almost always associated w/some degree of aspiration
• Amount of aspiration may be clinically insignificant
• Or, may be clinically significant enough to cause:
– Chronic cough
– Involuntary vocal fold closure
– Reactive airway disease
– Difficult to control asthma
– Pneumonia
– Bronchiectasis
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Laryngopharyngeal reflux disease
– Evaluation
• Esophagram
• Dual 24-hour pH probe
• Bravo capsule study
• Flexible fiberoptic endoscopy
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Laryngopharyngeal reflux disease
– Treatment
• Behavioral
• Chewable antacids
• Viscous antacids
• H2-receptor antagonists
• Proton pump inhibitors
• Nissen fundoplication/Stretta procedure
Chronic Illnesses/Disorders That Can Affect Laryngeal Function
• Smoking/alcohol abuse/illicit drug use
– Erythema/edema
– Generalized inflammation
– Drying of mucous membranes
– Incoordination/dysarthria/impaired judgment
– LPRD
– Chronic cough
Primary Disorder Etiologies That Can Affect Laryngeal Function
• Environmental stress – Loss of employment – Death of spouse/significant other – Family conflict
• Conversion behaviors – Avoidance behavior(s) developed to counteract stressful
situation(s) – Whispering, muteness, unusual dysphonias
• Identity conflict – Establishment of own personality
• High-pitched falsetto in post-pubescent adolescent • Weak, juvenile, thin-sounding voice of adult female • Raised pitch in male-to-female transsexual
Case Study #1
• 41 year-old female • Presenting Dx of “difficult to control asthma” • Trialed on multiple courses of different asthma
medications over a # of months w/no appreciable improvement in respiratory function
• No hx of smoking/excessive alcohol use • Presenting symptoms
– Chronic sense of chest tightness – Chronic restriction of inhalation/exhalation – Sense of “elephant sitting on chest” – Chronic hoarseness X12 months w/no Otolaryngologic
examination – Denied sense of throat constriction
Case Study #1
• Presenting symptoms not consistent with upper airway involvement
• Extended duration of hoarseness concerning
• Referral to Otolaryngology
• Fiberoptic endoscopic exam results – Marked endolaryngeal erythema/edema
– Laryngeal candidiasis
– No concerning lesions
Case Study #1
• Treatment
– Speech Pathology not involved in Tx
– Aggressive pharmacologic management of LPRD/candidiasis for six months
• Oral anti-fungal medication (swish/swallow)
• Anti-reflux management
– Rigid behavioral strategies
– 40mg PPI b.i.d. 30 minutes prior to oral intake
Case Study #1
• Results of treatment
– 40 lb. weight loss
– Return of baseline vocal functioning
– Return of baseline respiratory functioning
– Secondary to tx, QOL markedly improved
Irritable Larynx Syndrome
• Postulated by Morrison, Rammage, and Emami in 1999
• Suggests that various laryngeal behaviors can be categorized within the context of “hyperkinetic laryngeal dysfunction”
These Behaviors Include:
• Muscle Tension Dysphonia
• Episodic laryngospasm
• Globus sensation
• Cough
Muscle Tension Dysphonia
• Incoordination between respiration and phonation
• Above results in elevated levels of laryngeal/throat muscle tension
• In turn, contributes to general laryngeal hyperfunction – Laryngeal pain/discomfort
– Increased vocal effort
– Vocal fatigue
Muscle Tension Dysphonia
• In addition to elevated levels of tension in larynx/throat, can also contribute to increased tension in neck, shoulder, and upper chest musculature
– Can then masquerade as sensation of limited movement of air through the neck/throat area during inhalation
Episodic Laryngospasm
• Adduction of VFs during inhalatory phase of respiration • In differential Dx
– Involuntary Vocal Fold Closure – Adductory Laryngeal Breathing Dystonia – Closure of VFs as protective mechanism during reflux episode
• Somatoform/anxiety disorder? – Intrinsic/extrinsic stress vs. psychological issue – Larynx “Achilles heel” for stress/anxiety?
• Variations on a theme? – Asthma variant
• Functional? – Implies normal structure/function of larynx but inappropriate behavior
of the same
Globus
• “Lump in throat” sensation
• Secondary to increased levels of muscle tension in larynx? – Inappropriate resting or holding position of
laryngeal musculature
• Secondary to laryngopharyngeal reflux disease? – Laryngeal erythema/edema masquerading as
sensation of mucous
Cough
• Secondary to respiratory disease?
– Acute vs. chronic
– Productive vs. non-productive
• Secondary to laryngopharyngeal reflux disease?
• Increase in stress/anxiety?
– Stress vs. psychogenic
– Functional?
• Secondary to allergies?
• Neuropathic?
For All of These Behaviors
• Larynx appears structurally normal on visualization
• Abnormal laryngeal muscle posture present – Anteroposterior “squeeze” of laryngeal
complex
• Palpable laryngeal muscle tension present – Massage of thyroid cartilage/hyoid bone
results in pain, discomfort
Irritable Larynx Syndrome
• Defined as:
– “hyperkinetic laryngeal dysfunction resulting from an assorted collection of causes in response to a definitive triggering stimulus”
ILS – Inclusion Criteria
• Symptoms attributable to laryngeal tension – Dysphonia and/or laryngospasm
• With or without chronic cough • Visible and palpable evidence of tension
– Lateral and A/P compression of larynx during laryngoscopic examination
– Discomfort during laryngeal palpation
• Presence of sensory trigger(s) – Airborne substance – Esophageal irritant – Odors
ILS – Exclusion Criteria
• Apparent organic laryngeal pathology
• Identifiable neurologic disease
• Identifiable psychiatric diagnosis
Patients with Dx of ILS
• Tend to have complex combination of signs, symptoms, and background factors
• Laryngospasm and dysphonia are two major ILS symptoms – Laryngospasm most distressing to patient
• More minor symptoms – Globus
– Cough
– Perilaryngeal pain
• Above will vary from patient to patient
ILS Symptom Complex Grouping
• Laryngospasm alone
• Laryngospasm with dysphonia, globus, or cough
• Dysphonia alone
• Dysphonia with laryngospasm, globus, or cough
• Other
– Globus and/or cough
Triggering Stimuli
• Airborne irritants
• Reflux
• Perfumes/colognes
• Foods
• Emotions
• Voice use
• Exertion
Possible Etiologic Factors
• Reflux
• Viral
• Stress/Psychogenic
• Asthma
• Environmental allergy(ies)
• Torsion injury to neck/throat/larynx
Hypothesis for ILS
• Develops as reaction to some sort of CNS change that leaves sensorimotor pathways in state of hypersensitivity
• # of possible causative factors
• Several can be active in any one patient
• Most prevalent – Emotional distress
• Stress component vs. psychogenic cause
– Habitual inappropriate resting posture of laryngeal musculature
– LPRD
– Post-viral illness • Viral neuropathy
Treatment
• Reflux management – Behavioral/pharmacologic
• Exercises
• Stress management
• Massage/manipulation
• Non-reflux pharmacologic management – Botulinum Toxin A
– Nebulized topical anesthetic
– Amitriptyline/Gabepentin
Cough
• Important respiratory defense mechanism
• Responsible for clearance of excessive secretions, fluids, or foreign materials from the airway
• Despite this protective role, excessive coughing can result in multisystem issues
– Anxiety, dysphonia, fatigue, urinary incontinence, emesis, rib fracture(s), etc.
Cough – Differential Diagnosis
• Upper Respiratory Tract
• Allergic or vasomotor rhinitis, postnasal drip syndrome, infectious/post-infectious cough, sinusitis
Cough – Differential Diagnosis
• Lower Respiratory Tract • Abscess, allergic inflammation, aspiration, asthma, bronchiectasis, bronchitis, COPD, cystic fibrosis, drugs, eosinophilic bronchitis, interstitial lung disease, pertussis, primary or metastatic lung tumors, sarcoidosis, tuberculosis
Cough – Differential Diagnosis
• Cardiovascular system
• Gastrointestinal system
• Left ventricular failure, mitral stenosis, medications (ACE inhibitors)
• Reflux disease (laryngopharyngeal)
Cough – Differential Diagnosis
• Central Nervous System (psychological response)
• D’Urzo and Jugovic (2002)
• Habit cough, chronic cough, psychogenic cough, neuropathic cough
Cough – Clinical Presentation
• School age children to older adults
• Average length of cough months to years
• Most pts have attempted multiple interventions w/o resolving of cough
• Most have associated fatigue
• Most do not have accompanying hoarseness
• Most have been treated for reflux for a short period of time w/o success
Cough
• Habit/chronic cough – Larynx engaged in disordered loop of behavior
• Psychogenic cough – Cough occurs secondary to emotional/psychological issues
• Laryngeal hypersensitivity/hyper-reactivity – Larynx over-reacts to triggering stimuli secondary to irritation of
the larynx by refluxed stomach contents
• Neuropathic cough – Cough occurs secondary to viral neuropathy
• Cough Hypersensitivity Syndrome (Morice, 2009) – Th2-type immune response vs. reflux symptoms
Behavioral/Environmental History
• Nature of cough – Light dry coughs throughout the day – Severe/overwhelming cough “attacks”
• Pattern of cough – Occurs at specific time(s) of day? – Follow meals or specific activity(ies)? – Getting worse/remaining stable?
• Work/home/social environment – New building materials? – Ventilation relative to work space? – Dusty and/or dry environment?
Cough - Tx
• Habit/chronic cough – Behaviorally reposture larynx into appropriate pattern of functioning – Improve laryngeal environment – Improve awareness of sensations/behaviors that precipitate cough – Implement behavior to delay/eliminate the cough before it
“recalibrates” laryngeal sensitivity threshold
• Psychogenic cough – Behavioral/psychological treatment
• Laryngeal hypersensitivity/hyper-reactivity – Behavioral/aggressive reflux tx
• Neuropathic cough – Amitriptyline, Gabepentin
• Cough Hypersensitivity Syndrome – Treat causal phenotype appropriately
Involuntary Vocal Fold Closure
• Confusing disorder that is frequently mistaken for asthma or organic obstructive upper airway conditions
• Fully 78 different names for disorder in the literature
• Encompasses inappropriate vocal fold adduction during inhalation
IVFC - Symptoms
• Sudden onset
• Compromised inhalation
• Sensation of throat closure/tightness
• Inhalatory stridor
IVFC Mimicking Asthma
• IVFC
– Throat tightness, dysphonia during episodes – esp inhalation
– Little/no improvement w/use of bronchodilators during episodes
– No night awakening or cough unless associated with reflux-induced laryngospasm
• Asthma
– Chest tightness – esp exhalation
– Improvement w/use of bronchodilators
– Nighttime symptoms frequent
IVFC Mimicking Asthma
– Symptoms early in exercise – Recovery period 5-10
minutes – Turbulence at level of
larynx, +/- stridor – Pt able to pant/breath hold
during episode – may improve symptoms
– PFTs characterized by truncated inspiratory loop w/normal exhalatory loop w/no bronchodilator response
– Normal lung volumes – Female preponderance
– Symptoms later in exercise – Recovery period 15-60
minutes – Turbulence in lungs
w/wheeze, no stridor – Pt unable to pant/breath
hold when symptomatic – PFTs abnormal (airflow
obstruction) w/bronchodilator response
– Increased residual lung volume
– Males/females equally affected
IVFC
• Causal factors
– Functional or psychogenic issue?
– Laryngeal hypersensitivity/hyper-reactivity?
– Laryngospasm?
– Adductor laryngeal breathing dystonia (Blitzer and Brin, 1991; Grillone, et.al., 1994)
• Rare disorder whose symptoms are similar to IVFC
• Neurological issue
• Behavioral intervention not efficacious in management
IVFC - Evaluation
• History – Acute versus chronic issue?
– Episodes same/different w/regard to presentation?
– Episodes same/different w/regard to severity?
– Triggers
• Flexible endoscopy during/subsequent to challenge
• Spirometry
IVFC - Treatment
• Functional issue – Behavioral intervention
• Psychogenic issue – Behavioral/psychological treatment
• Laryngeal hypersensitivity/hyper-reactivity – Aggressive reflux management
• Laryngospasm – Aggressive reflux management, behavioral management, use of
Heliox if severe, tracheotomy if life-threatening
• Adductory laryngeal breathing disorder – Botulinum Toxin A injections
Case Study #2
• 13 year-old female
• Placed into foster care/living w/supportive foster mother
• Reason for placement – ongoing sexual/psychological abuse at hands of one parent w/other parent/family members unable/unwilling to intervene
• Patient actively pursuing legal severance of parental rights/involvement w/family
Case Study #2
• Parents/other family members under court order not to contact patient
• When court order violated, patient experienced episodes of dyspnea: sudden onset, sensation of throat constriction, compromised inhalation, and inhalatory stridor
Case Study #2
• During flexible endoscopy, sudden onset of VF adduction occurred
• Use of behavioral intervention efficacious in alleviating episode
• Episodes continued to occur but were effectively managed w/behavioral strategies
• Episodes ceased subsequent to legal severance of parental/family rights, adoption of patient by foster mother, and 18 months of psychotherapy
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