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Vocal Cord Dysfunction JAMES DECKERT, MD, Saint Louis University School of Medicine, St

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Vocal Cord Dysfunction JAMES DECKERT, MD, Saint Louis University School of Medicine, St. Louis, Missouri LINDA DECKERT, MA, CCC-SLP, Special School District of St. Louis County, Town & Country, Missouri Vocal cord dysfunction involves inappropriate vocal cord motion that produces partial airway obstruction. Patients may present with respiratory distress that is often mistakenly diagnosed as asthma. Exercise, psychological conditions, airborne irritants, rhinosinusitis, gastroesophageal reflux disease, or use of certain medications may trigger vocal cord dysfunction. The differential diagnosis includes asthma, angioedema, vocal cord tumors, and vocal cord paralysis. Pulmo- nary function testing with a flow-volume loop and flexible laryngoscopy are valuable diagnostic tests for confirming vocal cord dysfunction. Treatment of acute episodes includes reassurance, breathing instruction, and use of a helium and oxygen mixture (heliox). Long-term manage- ment strategies include treatment for symptom triggers and speech therapy. (Am Fam Physician. 2010;81(2):156-159, 160. Copyright © 2010 American Academy of Family Physicians.) ▲ Patient information: ocal cord dysfunction is a syn- been previously diagnosed with asthma.8 A handout on vocal cord drome in which inappropriate Most patients with vocal cord dysfunction dysfunction, written by the authors of this article, is vocal cord motion produces par- have intermittent and relatively mild symp- provided on page 160. tial airway obstruction, leading toms, although some patients may have pro- toV subjective respiratory distress. When a per- longed and severe symptoms. son breathes normally, the vocal cords move Laryngospasm, a subtype of vocal cord away from the midline during inspiration and dysfunction, is a brief involuntary spasm of only slightly toward the midline during expi- the vocal cords that often produces aphonia ration.1 However, in patients with vocal cord and acute respiratory distress. Laryngospasm dysfunction, the vocal cords move toward is a common complication of anesthesia.11 the midline during inspiration or expiration, Another variation of vocal cord dysfunc- which creates varying degrees of obstruction.2 tion is spasmodic dysphonia, which causes Vocal cord dysfunction has numerous labels hoarseness and strained vocalization when in the literature, including paradoxical vocal the abnormal vocal cord motion occurs dur- cord dysfunction,3 paradoxical vocal fold ing speech.12 motion,4 and factitious asthma.5 Differential Diagnoses Clinical Presentation The primary diagnosis to consider in patients Vocal cord dysfunction occurs more often in with respiratory distress or wheezing is women than in men, and is common in per- asthma. Vocal cord dysfunction is often mis- sons 20 to 40 years of age.2,6,7 However, stud- diagnosed as asthma, and a considerable sub- ies have identified vocal cord dysfunction in set of patients with vocal cord dysfunction adolescents and in children as young as eight also have asthma, making the diagnosis more years.8 difficult.2,8 A careful patient history may help Patients with vocal cord dysfunction typi- to differentiate between the two conditions. cally present with recurrent episodes of sub- Unlike asthma, vocal cord dysfunction causes jective respiratory distress that are associated more difficulty with inspiration than expira- with inspiratory stridor, cough, choking sen- tion, and is commonly associated with a sen- sations, and throat tightness.3 The presence sation of throat tightness or choking. However, of wheezing can indicate an asthma exacer- further testing, including pulmonary function bation, but is commonly a mistaken descrip- testing and laryngoscopy, is usually required tion of the stridor characteristic of vocal to make the diagnosis.13 Additional conditions cord dysfunction.9,10 In one study, 59 percent in the differential diagnosis of vocal cord dys- of patients with vocal cord dysfunction had function are listed in Table 1. 156 American Family Physician www.aafp.org/afp Volume 81, Number 2 ◆ January 15, 2010 Downloaded from the American Family Physician Web site at www.aafp.org/afp. Copyright © 2010 American Academy of Family Physicians. For the private, noncommercial use of one individual user of the Web site. All other rights reserved. Contact [email protected] for copyright questions and/or permission requests. Vocal Cord Dysfunction SORT: KEY RECOMMENDATIONS FOR PRACTICE Evidence Clinical recommendation rating References Exercise-induced vocal cord dysfunction should be strongly considered in patients diagnosed C 7, 8 with exercise-induced asthma who respond poorly to usual treatment. Pulmonary function testing with a flow-volume loop is useful in confirming a diagnosis of vocal C 2, 22-25 cord dysfunction. Reassurance and breathing instruction may resolve an acute episode of vocal cord dysfunction. C 27 Pretreatment with inhaled ipratropium (Atrovent) may be a helpful adjunct in patients with C 8 exercise-induced vocal cord dysfunction. A = consistent, good-quality patient-oriented evidence; B = inconsistent or limited-quality patient-oriented evidence; C = consensus, disease- oriented evidence, usual practice, expert opinion, or case series. For information about the SORT evidence rating system, go to http://www.aafp. org/afpsort.xml. ammonia, dust, smoke, soldering fumes, Table 1. Differential Diagnosis of Vocal Cord Dysfunction and cleaning chemicals. Studies have shown a clear temporal relationship between expo- Anaphylaxis Laryngotracheobronchitis (croup) sure and onset of symptoms.17 Angioedema Presence of foreign body RHINOSINUSITIS Asthma Tracheal stenosis Epiglottitis Vocal cord paralysis Postnasal drip associated with rhinosinusitis Hypoparathyroidism Vocal cord tumors or polyps has been linked to airway hyperresponsive- Laryngomalacia (in adults) ness.18 A high prevalence of rhinosinusitis in patients with vocal cord dysfunction and case reports of resolution of vocal cord dysfunc- Precipitating Factors tion symptoms with treatment suggest that rhinosinusitis Vocal cord dysfunction is associated with a variety of may play a role in some patients.17 precipitating factors, but no clear unifying pathophysi- ology has been identified. GASTROESOPHOGEAL REFLUX DISEASE Gastroesophageal reflux disease (GERD) has been impli- EXERCISE cated in triggering vocal cord dysfunction.19 In some Exercise is a common cause of vocal cord dysfunction. studies, a high prevalence of GERD was identified in Exercise-induced vocal cord dysfunction is often mis- patients with vocal cord dysfunction20; however, treat- diagnosed as exercise-induced asthma.8 It should be ment of GERD was only effective in decreasing vocal strongly considered in patients with dyspnea on exertion cord dysfunction in some patients. who have been diagnosed with exercise-induced asthma, particularly if they respond poorly to usual treatment Medication use with bronchodilators.7 Neuroleptic drugs, specifically phenothiazines, may cause transient vocal cord dysfunction. This appears to PSYCHOLOGICAL CONDITIONS be a focal dystonic reaction and is associated with extra- Studies have reported associations between vocal cord pyramidal signs, such as torticollis.21 dysfunction and multiple psychological conditions, including posttraumatic stress disorder, anxiety, depres- Diagnostic Approaches sion, and panic attack.14 Anxiety disorders appear to be The most valuable diagnostic tests for vocal cord dys- particularly common in adolescent patients with vocal function are pulmonary function testing with a flow- cord dysfunction.15 However, associated depression and volume loop and flexible laryngoscopy. Other testing, anxiety may also be consequences of persistent respira- such as measurement of arterial blood gases, may be use- tory symptoms, rather than causes.16 ful in ruling out other possible diagnoses. IRRITANTS PULMONARY FUNCTION TESTING Exposure to environmental and occupational irritants Pulmonary function testing with a flow-volume loop is has been found to precipitate respiratory symptoms con- the most commonly used diagnostic test to confirm vocal sistent with vocal cord dysfunction. Common airborne cord dysfunction. In the flow-volume loop, it is typical irritants associated with vocal cord dysfunction include for the expiratory loop to be normal and the inspiratory January 15, 2010 ◆ Volume 81, Number 2 www.aafp.org/afp American Family Physician 157 Vocal Cord Dysfunction 14 14 13 13 12 12 11 11 10 10 9 9 loop to be flattened, which is consistent with 8 8 an extrathoracic upper airway obstruction 7 7 6 6 (Figure 1). This pattern is characteristic of 5 5 patients when they are symptomatic.22 Even 4 4 when asymptomatic, some patients with 3 3 second) 2 2 vocal cord dysfunction will demonstrate 1 1 per 2 0 0 inspiratory loop flattening. Exercise flow- 43210 5 543210 -1 -1 volume loops, performed in conjunction -2 -2 (liters with exercise testing, may be useful in iden- -3 -3 -4 -4 tifying patients with exercise-induced vocal Flow -5 -5 cord dysfunction.23 -6 -6 -7 -7 Pulmonary function testing is particu- -8 -8 larly useful in differentiating vocal cord -9 -9 -10 -10 dysfunction from asthma because bron- -11 -11 chospasm produces an impaired expiratory -12 -12 -13 -13 loop that is different from that seen in vocal -14 -14 24 cord dysfunction. In cases with an unclear Volume (liters) etiology, or if concurrent asthma and vocal cord dysfunction are suspected, methacho- Figure 1. Flow-volume loop. (Left) Normal expiratory and inspiratory line challenge
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