CE/CME

Vocal Cord Dysfunction: Unmasking the Asthma Pretender

Clinician Reviews. 2014 December;24(12):18-24

References

1. Hoyte FCL. Vocal cord dysfunction. Immunol Allergy Clin N Am. 2013;33:1-22.

2. Ibrahim WH, Gheriani HA, Almohamed AA, Raza T. Paradoxical vocal cord motion disorder: past, present and future. Postgrad Med J. 2007;83:164-172.

3. Powell DM, Karanfilov BI, Beechler KB, et al. Paradoxical vocal cord dysfunction in juveniles. Arch Otolaryngol Head Neck Surg. 2000;126(1):29-34.

4. Husein OF, Husein TN, Gardner R, et al. Formal psychological testing in patients with paradoxical vocal fold dysfunction. Laryngoscope. 2008; 118(4):740-747.

5. Dunglison RD. The Practice of Medicine. Philadelphia, PA: Lea and Blanchard; 1842:257-258.

6. MacKenzie M. Use of Laryngoscopy in Diseases of the Throat. Philadelphia, PA: Lindsey and Blackeston; 1869:246-250.

7. Osler W. Hysteria. In: The Principles and Practice of Medicine. 4th ed. New York, NY: Appleton; 1902:1111-1112.

8. Patterson R, Schatz M, Horton M. Munchausen’s stridor: non-organic laryngeal obstruction. Clin Allergy. 1974;4:307-310.

9. Christopher KL, Wood RP 2nd, Eckert RC, et al. Vocal cord dysfunction presenting as asthma. N Engl J Med. 1983;308(26):1566-1570.

10. Christopher KL. Understanding vocal cord dysfunction: a step in the right direction with a long road ahead. Chest. 2006;129(4):842-843.

11. Christopher KL, Morris MJ. Vocal cord dysfunction, paradoxic vocal fold motion, or laryngomalacia? Our understanding requires an interdisciplinary approach. Otolaryngol Clin N Am. 2010;43:43-66.

12. Sasaki CT, Weaver EM. Physiology of the larynx. Am J Med. 1997;103:9S-18S.

13. Balkissoon R. Occupational upper airway disease. Clin Chest Med. 2002;23:717-725.

14. Murakami Y, Kirschner JA. Mechanical and physiological properties of reflex laryngeal closure. Ann Otol Rhinol Laryngol. 1972;81(1):59-71.

15. Forrest LA, Husein T, Husein O. Paradoxical vocal cord motion disorder: classification and treatment. Laryngoscope. 2012;122:844-853.

16. Altman KW, Simpson CB, Amin MR, et al. Cough and paradoxical vocal fold motion. Otolaryngol Head Neck Surg. 2002;127(6):501-511.

17. Freedman MR, Rosenberg SJ, Schmaling KB. Childhood sexual abuse in patients with paradoxical vocal cord dysfunction. J Nerv Ment Dis. 1991;179(5):295-298.

18. Buddiga P. Vocal cord dysfunction. Medscape. http://emedicine.medscape.com/article/137782-overview. Accessed November 12, 2014.

19. Chiang T, Marcinow AM, deSilva BW, et al. Exercise-induced paradoxical vocal fold motion disorder: diagnosis and management. Laryngoscope. 2013;123:727-731.

20. Morris MJ, Deal LE, Bean DR, et al. Vocal cord dysfunction in patients with exertional dyspnea. Chest. 1999;116(6):1676-1682.

21. Hicks M, Brugman SM, Katial R. Vocal cord dysfunction/paradoxical vocal fold motion. Prim Care. 2008;35(1):81-103.

22. Maschka DA, Bauman NM, McCray PB, et al. A classification scheme for paradoxical vocal fold motion. Laryngoscope. 1997;107(11):1429-1435.

23. Uloza V, Vegiene A, Pribuisiene R, Saferis V. Quantitative evaluation of video laryngostroboscopy: reliability of the basic parameters. J Voice. 2013;27(3):361-368.

24. Pitchenik AF. Functional laryngeal obstruction relieved by panting. Chest. 1991;100(5):1465-1467.

25. Deckert J, Deckert L. Vocal cord dysfunction. Am Fam Physician. 2010;81(2):156-160.

26. Carding PN, Horsley IA, Docherty GJ. A study of the effectiveness of voice therapy in the treatment of 45 patients with nonorganic dysphonia. J Voice. 1999;13(1):72-104.

DIFFERENTIAL DIAGNOSIS
Distinguishing VCD from other disorders can be challenging. Differential diagnosis should include
• Non–vocal cord adduction disorders, such as thyroid goiter, upper airway hemorrhage, caustic ingestion, neoplastic disorders, rheumatoid cricoarytenoid arthritis, pharyngeal abscess, angioedema, pulmonary embolus²¹
• Anatomic defects (eg, laryngomalacia, subglottic stenosis)
• Tracheal masses (eg, enlarged thyroid gland)
• Vocal cord polyps
• Laryngospasm
• Vocal cord paresis
• Neurologic causes (eg, brain stem compression, severe cortical injury, nuclear or lower motor neuron injury, movement disorders)
• Nonorganic causes (eg, factitious symptoms or malingering; conversion disorder)²²• Reactive airway disease.
Some disorders are easier to distinguish from VCD than others. For example, although laryngospasm may produce similar symptoms, episodes are brief, lasting seconds to minutes; VCD episodes may last hours to days.

Asthma
Even the most astute clinician will be unable to obtain adequate information from the patient history to differentiate VCD from asthma. There is a significant overlap of symptoms—shortness of breath, cough, wheezing—and frequently, the diseases coexist. History is often negative for chest pain, but it is common for patients with VCD, when asked to describe their symptoms, to report chest tightness. The clinician therefore needs to ask the patient to point to where the tightness is felt—in the chest or in the neck over the laryngeal area—to distinguish the source.

Asthma symptoms usually increase over a few hours, days, or weeks but respond to medications that open the airway and reduce inflammation (inhaled β-agonists and corticosteroids). VCD symptoms usually occur or decrease suddenly and do not respond well to traditional asthma treatments.

Other differences between asthma and VCD symptoms include voice changes and time of day when symptoms occur. The person with VCD will experience voice changes, such as hoarseness, as well as prolonged coughing episodes. Patients with asthma may awaken at night because of breathlessness, while most patients with VCD experience symptoms only during the day.

The diagnosis is generally confirmed if VCD is seen on direct laryngoscopic visualization during a symptomatic episode. In terms of adduction, the anterior cords will appear normal, but the posterior portion of the cords will display the classic “glottis chink” (see Figure 2).⁹

If the diagnosis is in question, videostroboscopy, a technique that provides a magnified slow-motion view of vocal cord vibration, can help identify or exclude pathologic conditions of the vocal cords.²³

Convincing the patient of the validity of the diagnosis may be problematic if the patient has been previously diagnosed with and treated for another condition. The diagnosis should be explained and the patient counseled what appropriate care for VCD entails (see discussion under “Patient education and self-care”).

TREATMENT
Acute episode
During an acute VCD episode, offering the patient calm reassurance can be effective in resolving the episode. Simple breathing guidance may also be beneficial; instructing the patient to breathe rapidly and shallowly (ie, pant) can result in immediate resolution of symptoms.²⁴ The patient can be advised to utilize other techniques, such as diaphragmatic breathing, breathing through the nose, breathing through a straw, pursed-lip breathing, and exhaling with a hissing sound.²⁵

Long-term management
Although various strategies are employed in the management of VCD, well-designed studies on which to base treatment decisions have not been performed. Of course, control and management of possible underlying triggers or disorders should be implemented. Because etiology is rarely known, treatment for VCD is generally empiric.

Evidence does exist, however, to suggest that voice therapy, the treatment of choice for muscle tension dysphonia, is also effective for VCD. Speech therapy with specific voice and breathing exercises can enable the patient to manage the condition, thereby reducing ED visits, hospitalizations, and treatment costs.²⁶

Patient education and self-care
Patient education is a critical component of VCD management. The clinician should explain the functions of the larynx to the patient, including the normal functioning of the vocal cords during respiration, speaking, swallowing, coughing, throat clearing, and breath holding. It may also enhance patients’ understanding of VCD to view their diagnostic laryngoscopy or videostroboscopy films.²¹

The patient should be advised to rest the voice, hydrate, utilize sialagogues (lozenges, gum) to stimulate salivation, reduce exposure to triggers when possible, and decrease stress. She should be encouraged to track VCD triggers by documenting what she is doing, where, and when, at the time of a VCD episode.

Two exercises—“paused breathing” and “belly breathing”—can be used by patients to learn how to relax the vocal cords (see “Patient Handout”). Patients should practice these exercises three times a day so that they can be easily recalled and performed during VCD episodes.

Continue for outcomes >>