Vocal Cord Dysfunction

Aka: Vocal Cord Dysfunction, Paradoxical Vocal Cord Dysfunction, Paradoxical Vocal Fold Motion, Factitious Asthma, Munchausen's Stridor, Functional Dysphonia, Spasmodic Dysphonia, Episodic Laryngeal Dyskinesia, Psychosomatic Stridor, Inducible Laryngeal Obstruction

1. See Also
   1. Dysphonia
   2. Functional Aphonia
2. Definitions
   1. Vocal Cord Dysfunction
      1. Inappropriate vocal cord motion transiently obstructs airway
      2. Vocal Cords remain in adduction despite inspiration
3. Epidemiology
   1. Peak age 30-40 years
   2. Gender: Female predominance (2-3 fold more than males)
4. Pathophysiology
   1. Inducible Laryngeal Obstruction
   2. Paradoxical vocal cord closure (e.g. during inspiration) resulting in impaired respiration and altered voice
5. Symptoms
   1. Hoarseness, Dysphonia or Aphonia
      1. Associated with less severe episodes
   2. Dyspnea
      1. Recurrent episodes
      2. Throat tightness
      3. Chest tightness
      4. Choking Sensation
   3. Stridor
      1. Stridor may be mis-reported by patients as Wheezing
6. Signs
   1. View patient obtained video if available as exam is typically normal outside of episodes
   2. Sudden onset of severe Dyspnea without associated Hypoxia, Tachypnea or increased work of breathing
   3. Inspiratory Stridor
7. Causes: Precipitating factors of Vocal Cord Dysfunction
   1. Exercise
      1. May present as Exercise induced Asthma
   2. Psychiatric conditions
      1. Common in adolescents, but anxiety may also be triggered related to the unsettling nature of this condition
      2. Anxiety Disorder (e.g. Panic Attack, Generalized Anxiety Disorder, PTSD, Performance Anxiety)
      3. Major Depression
      4. Obsessive Compulsive Disorder
   3. Environmental Irritants (airborne)
      1. Ammonia and other cleaning chemicals
      2. Dust
      3. Smoke
      4. Fumes
   4. Sinusitis or recent Upper Respiratory Infection
      1. Consider nasal steroid trial (e.g. Flonase)
      2. Consider antibiotic course
   5. Gastroesophageal Reflux disease
      1. Proton Pump Inhibitors are variably effective in improving Vocal Cord Dysfunction even when GERD is primary trigger
   6. Extrapyramidal Side Effects
      1. Focal Dystonic Reaction to Neuroleptic drugs (Antipsychotics)
8. Associated Conditions
   1. Asthma (25-30% of cases)
   2. Gastroesophageal Reflux
   3. Anxiety Disorder
9. Imaging
   1. Chest XRay
      1. Evaluate differential diagnosis (upper chest mass resulting in compression)
   2. Lateral Neck XRay
      1. Consider for evaluation of the epiglottis in the acute setting
10. Diagnostics
    1. Pulmonary Function Test (PFT)
       1. Flow volume loop shows flattened inspiratory portion of the curve
       2. FEF50/FIF50 >1
          1. Where FEF50 is Expiratory Flow at 50% of Forced Vital Capacity (FVC)
          2. Where FIF50 is Inspiratory Flow at 50% of Forced Vital Capacity (FVC)
       3. Consider Methacholine Challenge
          1. Evaluate for Asthma in differential diagnoses
    2. Nasolaryngoscopy (flexible Laryngoscopy)
       1. Diagnostic with direct visualization of the cords
       2. Directly observe abnormal vocal cord movement to the midline on inspiration or expiration
       3. Provocative maneuvers performed under direct visualization improve Test Sensitivity
          1. Panting
          2. Exercise
          3. Deep breathing
          4. Phonating
11. Differential Diagnosis
    1. See Stridor
    2. Asthma (most common)
    3. Hypothyroidism
    4. Acute upper airway conditions
       1. Anaphylaxis or Angioedema
       2. Epiglottitis
       3. Croup
       4. Airway Foreign Body
    5. Chronic airway structural conditions
       1. Laryngomalacia (adults)
       2. Subglottic Stenosis or Tracheal stenosis
       3. Tracheal Mass
    6. Vocal cord specific disorders
       1. Vocal Cord Paralysis
       2. Vocal Cord Polyp and other vocal cord neoplasm
    7. Other neurologic conditions
       1. Amyotrophic Lateral Sclerosis
       2. Vagus Nerve Injury
       3. Recurrent Laryngeal Nerve Injury
12. Management: Emergency Department evaluation of undifferentiated Stridor
    1. See Awake Nasotracheal Intubation
    2. Maintain airway and consider differential diagnosis
    3. Ready all airway management equipment (RSI, intubation, failed airway)
    4. Evaluate and manage acute Asthma
13. Management: Short-Term symptomatic relief
    1. Remember that patients do not have volitional control over airway obstruction
    2. Be prepared for Advanced Airway and failed airway measures if case Stridor cause is not functional
    3. Maneuvers that help relieve acute symptoms
       1. Panting
       2. Diaphragmatic breathing
       3. Nasal breathing
       4. Breathing through a short straw
       5. Pursed-lip breathing
       6. Make hissing sound during expiration
       7. "Rescue Breaths" Technique
          1. https://www.youtube.com/watch?v=cKHd935oRBg
    4. Other measures: Severe or persistent symptoms
       1. Epinephrine neb (5 ml of 1 mg/ml, 1:000 Epinephrine)
       2. Ipratropium Bromide (Atrovent) Inhaler
       3. Heliox
       4. Anxiolysis with Benzodiazepine (e.g. 1 mg Ativan)
       5. Ketamine
          1. Not studied, but has been used anecdotally with good success in acute severe Stridor
          2. Paradoxical Vocal Cord Dysfunction episodes often resolves (anecdotally) with Ketamine
          3. Ketamine may uncommonly cause laryngospasm (be ready with paralytics and Advanced Airway)
          4. Braude et al in Herbert (2015) EM Rap 15(2): 3-4
14. Management: Long-Term elimination of underlying causes
    1. Treat causes above
       1. Consider Sinusitis Management (e.g. nasal steroid, antibiotic)
       2. Consider GERD management (e.g. Proton Pump Inhibitor)
       3. Eliminate airborne irritants
       4. Review possible medication triggers (e.g. Antipsychotic Medications)
       5. Manage Asthma
    2. Speech therapy
       1. Therapeutic breathing Exercises including relaxed throat breathing
       2. Vocal cord Relaxation Techniques
    3. Otolaryngology Consultation
       1. Consider Botox Injection for Spasmodic Dysphonia
15. Management
    1. Deckert (2010) Am Fam Physician 81(2): 156-9 [PubMed]
    2. Malaty (2021) Am Fam Physician 104(5): 471-5 [PubMed]
    3. Mathers-Schmidt (2001) Am J Speech Lang Pathol 10(2): 111-25 [PubMed]
    4. Morris (2006) Clin Pulmonary Med 13(2): 73-86 [PubMed]
    5. Newsham (2002) J Athl Train 37(3): 325-8 [PubMed]