Coexistent asthma and functional upper airway obstruction. Case reports and review of the literature

A review of upper airway physiology relevant to the delivery and deposition of inhalation aerosols

Developing effective oral inhaled drug delivery treatment strategies for respiratory diseases necessitates a thorough knowledge of the respiratory system physiology, such as the differences in the airway channel's structure and geometry in health and diseases, their surface properties, and mechanisms that maintain their patency. While respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma and their implications on the lower airways have been the core focus of most of the current research, the role of the upper airway in these diseases is less known, especially in the context of inhaled drug delivery. This is despite the fact that the upper airway is the passageway for inhaled drugs to be delivered to the lower airways, and their replicas are indispensable in current standards, such as the cascade impactor experiments for testing inhaled drug delivery technology. This review provides an overview of upper airway collapsibility and their mechanical properties, the effects of age and gender on upper airway geometry, and surface properties. The review also discusses how COPD and asthma affect the upper airway and the typical inhalation flow characteristics exhibited by the patients with these diseases.

Can flow-volume loops be used to diagnose exercise induced laryngeal obstructions? A comparison study examining the accuracy and inter-rater agreement of flow volume loops as a diagnostic tool

Background:

Pre- and post-exercise flow-volume loops are often recommended as an easy non-invasive method for diagnosing or excluding exercise-induced laryngeal obstructions in patients with exercise-related respiratory symptoms. However, at present there is no evidence for this recommendation.

Aims:

To compare physician evaluated pre- and post-exercise flow-volume loops and flow data with laryngoscopic findings during exercise.

Methods:

Data from 100 consecutive exercise tests with continuous laryngoscopy during the test were analysed. Laryngoscopic images were compared with the corresponding pre- and post-exercise flow-volume loops assessed by four separate physicians and with data from the loops (forced inspiratory flow (FIF) at 25% vs. FIF at 75% of forced inspiratory vital capacity (FIVC), forced expiratory flow at 50% of forced expiratory volume vs. FIF at 50% of FIVC, and FIVC vs. FIF at 50% of FIVC).

Results:

There was no significant association between the laryngoscopic findings and the flow-volume data. There was no agreement between the four physicians in their assessment of the flow-volume loops (kappa <0.00), and none of the individual physician's assessments were significantly associated with the laryngoscopic findings.

Conclusions:

Exercise-induced laryngeal obstructions cannot be diagnosed or excluded by physician evaluated pre- and post-exercise flow-volume loops or flow data alone.

A novel scoring system to distinguish vocal cord dysfunction from asthma

BACKGROUND

Vocal cord dysfunction is often misdiagnosed and mistreated as asthma, which can lead to increased and unnecessary medication use and increased health care utilization.

OBJECTIVE

To develop a valid scoring index that could help distinguish vocal cord dysfunction from asthma.

METHODS

We compared the demographics, comorbidities, clinical symptoms, and symptom triggers of subjects with vocal cord dysfunction (n = 89) and those with asthma (n = 59). By using multivariable logistic regression, we identified distinguishing features associated with vocal cord dysfunction, which were weighted and used to generate a novel score. The scoring index also was tested in an independent sample with documented vocal cord dysfunction (n = 72).

RESULTS

We identified symptoms of throat tightness and dysphonia, the absence of wheezing, and the presence of odors as a symptom trigger as key features of vocal cord dysfunction that distinguish it from asthma. We developed a weighted index based on these characteristics, the Pittsburgh Vocal Cord Dysfunction Index. By using a cutoff of ≥4, this index had good sensitivity (0.83) and specificity (0.95) for the diagnosis of vocal cord dysfunction. The scoring index also performed reasonably well in the independent convenience sample with laryngoscopy-proven vocal cord dysfunction and accurately made the diagnosis in 77.8% of subjects.

CONCLUSION

The Pittsburgh Vocal Cord Dysfunction Index is proposed as a simple, valid, and easy-to-use tool for diagnosing vocal cord dysfunction. If confirmed by a prospective evaluation in broader use, it may have significant clinical utility by facilitating a timely and accurate diagnosis of vocal cord dysfunction, thereby preventing misdiagnosis and mistreatment as asthma. Future prospective validation studies will need to be performed.

Dynamic upper airway obstruction secondary to severe feline asthma

A 2 yr old castrated male cat presented to an emergency referral facility for several episodes of gagging, nonproductive coughing, and increased respiratory effort. He was diagnosed with inspiratory stridor and referred to another emergency referral practice for further diagnostics. Three separate, sedated oral examinations, nasal computed tomography (CT), rhinoscopic biopsies, and tracheoscopy showed no structural causes for the cat's stridor. An endotracheal wash was consistent with feline asthma. Blood work showed a peripheral eosinophilia and exposure to Dirofilaria immitis (D. immitis). The feline asthma was treated with albuterol, fluticasone, dexamethasone sodium phosphate, and terbutaline. Despite aggressive therapy for feline asthma, the cat had several episodes of severe inspiratory respiratory distress and stridor secondary to an upper airway obstruction. After 3 days of hospitalization, a temporary tracheostomy was performed and no further episodes of respiratory distress were noted. The tracheostomy tube was removed 3 days later, and the cat was discharged on the fourth day. At a 14 mo follow-up examination, the client reported no further episodes of respiratory distress, coughing, or gagging. To the authors' knowledge, this is the first report of dynamic upper airway obstruction secondary to feline asthma.

Elongated uvula and diagnostic utility of spirometry in upper airway obstruction

Elongated uvula is relatively an uncommon condition. Upper airway obstruction is often a missed complication of such a rare condition. Clinical presentations of upper airway obstruction often mimic asthma. Hence it is very easily mis-diagnosed as asthma. Spirometry offers a very simple test to diagnose upper airway obstruction very early and easily. Once diagnosed, the management of elongated uvula, almost exclusively, is surgical excision leading to total cure. Here is a case report of such a rare condition.

Irritant vocal cord dysfunction and occupational bronchial asthma: differential diagnosis in a health care worker

OBJECTIVES

Vocal cord dysfunction (VCD) is an uncommon respiratory disease characterized by the paradoxical adduction of vocal cords during inspiration, that may mimic bronchial asthma. The pathogenesis of VCD has not been clearly defined but it is possible to recognize non-psychologic and psychologic causes. The majority of patients are female but, interestingly, a high incidence of VCD has been documented in health care workers. A misdiagnosis with asthma leads to hospitalisation, unnecessary use of systemic steroids with related adverse effects, and sometimes tracheostomy and intubation. In a subset of VCD patients, the disease can be attributed to occupational or environmental exposure to inhaled irritants.

MATERIALS AND METHODS

We report the case of a 45-year-old woman, working as a nurse, who complained of wheezing, cough, dyspnoea related to inhalation of irritating agents (isopropylic alcohol, formaldehyde, peracetic acid). She underwent chest radiography, pulmonary function assessment both in the presence and in the absence of symptoms, bronchial provocation with methacholine and bronchodilation test with salbutamol to recognize asthma's features, allergy evaluation by skin prick tests and patch tests and video-laryngoscopy.

RESULTS

VCD diagnosis was made on the basis of video-laryngoscopy, that visualized the paradoxical motion of the vocal cords during symptoms, in the absence of other pathologic processes.

CONCLUSIONS

This case fulfils the proposed criteria for the diagnosis of irritant VCD (IVCD). This is the first report of VCD onset following exposure to several irritants: formaldehyde, glutaraldehyde, sopropylic alcohol, peracetic acid-hydrogen peroxide mixture. These substances are used as cleaning and antiseptic agents in healthcare settings and some ones can also be found in many indoor environments. A correct diagnosis is important both to give the appropriate treatment and for medical legal implications.

Vocal cord dysfunction: beyond severe asthma

BACKGROUND

Vocal cord dysfunction (VCD) is the abnormal adduction of the vocal cords during inspiration causing extrathoracic airway obstruction. VCD has been described as a confounder of severe asthma. The influence of VCD among less severe asthmatics has not been previously defined.

METHODS

We retrospectively reviewed the medical records of 59 patients with pulmonologist-diagnosed asthma who were referred for videolaryngostroboscopy (VLS) testing from 2006 to 2007.

RESULTS

A total of 44 patients had both asthma and VCD. 15 patients had asthma without concomitant VCD. Females were predominant in both groups. Overall, the majority of patients referred for VLS testing had mild-to-moderate asthma (78%) and 72% of these patients had VCD. Few patients from either group had "classic" VCD symptoms of stridor or hoarseness. Gastroesophageal reflux disease (GERD) and rhinitis were common in both groups.

CONCLUSIONS

Vocal cord dysfunction occurs across the spectrum of asthma severity. There was a lack of previously described "classic" VCD symptoms among asthmatics. Symptoms were diverse and not easily distinguished from common symptoms of asthma, highlighting the need for a high index of suspicion for VCD in patients with asthma. Failure to consider and diagnose VCD may result in misleading assumptions about asthma control, and result in unnecessary adjustments of asthma medications. The high prevalence of GERD raises the question of the role of acid reflux in the pathogenesis of VCD in asthmatics.

Paradoxical vocal cord motion disorder: past, present and future

Paradoxical vocal cord motion disorder (PVCM), also called vocal cord dysfunction, is an important differential diagnosis for asthma. The disorder is often misdiagnosed as asthma leading to unnecessary drug use, very high medical utilisation and occasionally tracheal intubation or tracheostomy. Laryngoscopy is the gold standard for diagnosis of PVCM. Speech therapy and psychotherapy are considered the cornerstone of management of this disorder. The aim of this article is to increase the awareness of PVCM among doctors, highlighting the main characteristics that distinguish it from asthma and discuss the recent medical achievements and the possible future perspectives related to this disorder.

Laryngeal dyskinesia: an under-recognized condition

OBJECTIVE

To perform a review of the epidemiology, pathogenesis, clinical presentation, diagnosis and management of laryngeal dyskinesia.

METHODS

A search of the Medline database from 1966 to 2003 was performed. A manual search was performed of the references of each article.

RESULTS

Laryngeal dyskinesia is a respiratory condition characterized by abnormal vocal cord adduction and airflow limitation at the level of the larynx in the absence of evidence of local organic disease. It typically presents to the ED as wheeze, stridor or apparent upper airway obstruction. It occurs across a wide age range, is more common in females, and is typically associated with a range of underlying psychopathologies. Diagnosis is often delayed and unnecessary emergency treatment such as intubation and tracheostomy is not uncommon. Patients are commonly on high-dose steroids and are frequent users of the health-care system, often over prolonged periods. There are multiple diagnostic features on history and examination, and flexible nasendoscopy of the vocal cords in the ED can be used to confirm the diagnosis. Treatment options in the ED include sedation and use of continuous positive airway pressure. Long-term treatment involves a multidisciplinary approach involving respiratory physicians/ear, nose and throat surgeons, speech therapy and psychiatry.

CONCLUSION

Laryngeal dyskinesia remains an under-appreciated cause of respiratory presentations to the ED. Emergency physicians are ideally placed to make the diagnosis and initiate appropriate referral for specific therapies that have a high level of success.

Paradoxical vocal cord motion--a dangerous imitator of airway emergencies

We report a case of stridor in a 32 year old woman. Initial laryngoscopy demonstrated adduction of the vocal cords on inspiration, which reverted to abduction on induction of general anaesthesia. The airway was structurally normal. The most likely diagnosis was paradoxical vocal cord motion, a condition in which psychological stress can precipitate respiratory symptoms and signs due to involuntary adduction of the vocal cords during inspiration. Its importance to the anaesthetist lies in its ability to masquerade as a serious airway or respiratory condition.

Non-rapid eye movement sleep parasomnias

Parasomnias are unpleasant or undesirable behavioral or experiential phenomena that occur during sleep. Once believed unitary phenomena related to psychiatric disorders, it is now clear that parasomnias result from several different phenomena and usually are not related to psychiatric conditions. Parasomnias are categorized as primary (disorders of the sleep states) and secondary (disorders of other organ systems that manifest themselves during sleep). Primary sleep parasomnias can be classified according to the sleep state of origin: rapid eye movement sleep, non-rapid eye movement sleep, and miscellaneous (those not respecting sleep state). Secondary sleep parasomnias are classified by the organ system involved.

Vocal cord dysfunction induced by methacholine challenge testing

STUDY OBJECTIVES

To determine whether methacholine challenge testing (MCT) provokes vocal cord dysfunction (VCD), as evidenced by inspiratory vocal cord closure on direct laryngoscopy, and whether spirometry and flow-volume loops (FVLs) demonstrate any changes that are suggestive of VCD.

DESIGN

Prospective, controlled study.

SETTING

Army medical center.

PATIENTS

Thirty-four subjects all with normal baseline spirometry. Ten subjects had documented evidence of VCD, 12 subjects had exercise-induced asthma (EIA) and reactive MCT, and 12 subjects served as healthy asymptomatic control subjects.

METHODS

Measurement of spirometry with FVLs and direct laryngoscopy of the vocal cords performed immediately before and after subjects had undergone MCT.

RESULTS

Evidence of inspiratory vocal cord adduction was found in four VCD patients. Two patients had adducted vocal cords at baseline, and their conditions were unchanged after undergoing MCT. Two other patients had normal conditions at baseline and demonstrated acute inspiratory vocal cord adduction after undergoing MCT. None of the patients in the EIA or control groups had evidence of VCD at baseline or after undergoing MCT. Truncation of the inspiratory limb of the FVL after MCT was noted in five patients, which correlated with evidence of VCD in 60% of these patients. One EIA patient had truncation of the inspiratory FVL after MCT, and no changes were found in the control group. A comparison of spirometry between EIA patients and VCD patients with and without evidence of inspiratory vocal cord adduction during MCT showed no significant differences.

CONCLUSIONS

The findings suggest that MCT may cause an acute episode of vocal cord adduction and that positive results may not reflect underlying reactive airways disease. However, a flattening or truncation of the inspiratory FVL after the patient undergoes MCT is not diagnostic for the presence of inspiratory vocal cord adduction.

Functional symptoms confused with allergic disorders in children and adolescents

The diagnosis of a functional respiratory disorder is sometimes difficult and time-consuming, because the symptoms often resemble those of organic diseases. The most common entities are hyperventilation syndrome, psychogenic cough, sighing dyspnea, and vocal cord dysfunction. Typical signs are heavy breathing or dyspnea, cough or sneezing, various breathing sounds, tightness of the throat or chest, pain, and fear. Criteria for differentiation include the lack of nocturnal symptoms, the sudden occurrence, no typical trigger factors, the variable duration, a quick regression, and that symptoms do not respond to adequate pharmacotherapy and finally normal results of diagnostic work-up. Therapeutic options comprise psychological intervention (by reassurance, relaxation techniques, and behaviour therapy) and physiotherapy (e.g. breathing therapy, voice training). Intensive efforts should be made to diagnose functional symptoms at an early stage because this will prevent stigmatization and fixation of symptoms and disease, and also prevent children from undergoing unnecessary and potentially harmful therapies.

Atypical expiratory flow volume curve in an asthmatic patient with vocal cord dysfunction

BACKGROUND

Vocal cord dysfunction can coexist with or masquerade as asthma. Vocal cord dysfunction, when coexistent with asthma, contributes substantially to the refractory nature of the respiratory problem.

OBJECTIVE

To report a case of an asthmatic patient with vocal cord dysfunction and a previously unreported unique expiratory flow volume curve.

RESULTS

A 16-year-old female, known to have asthma, developed increased frequency of her asthma exacerbations. Spirometry, during symptoms, showed an extrathoracic airway obstruction with a reproducible unique abrupt drop and rise in the expiratory flow volume loop. Laryngoscopy showed adduction of the vocal cords during inspiration and expiration.

CONCLUSIONS

We report a unique expiratory flow volume curve in an asthmatic with vocal cord dysfunction that resolved with panting maneuvers. Speech and psychological counseling helped prevent future attacks.

Clinical aspects of obstructive lung disease

Obstructive pulmonary diseases are diverse with an extensive differential diagnosis. Most cases can be diagnosed after a systematic evaluation that includes detailed history, physical examination, routine laboratory testing, radiologic and pulmonary physiologic tests. More specific studies are indicated only in a few patients.

Wheezing and vocal cord dysfunction mimicking asthma

Vocal cord dysfunction (VCD) is a respiratory disorder characterized by paradoxical closure of the vocal cords during the respiratory cycle leading to obstructive airway symptoms. The presenting symptoms vary from stridor to wheezing. VCD may coexist with asthma or masquerade as asthma. Misdiagnosis of VCD as asthma leads to inappropriate use of systemic steroids with its adverse effects, frequent emergency department visits, hospitalization, and, rarely, intubation and tracheostomy. Attenuation of the inspiratory flow volume loop on spirometry is suggestive of VCD. Laryngoscopic demonstration of the paradoxical vocal cord movements during an acute attack is the gold standard for the diagnosis of VCD. Patient education, speech therapy, and psychologic counseling are the therapeutic tools for treatment.

Paradoxical vocal fold motion: presentation and treatment options

Paradoxical vocal fold motion is a rare disorder in which adduction of the folds occurs on inspiration. The disorder presents with signs of airway obstruction and often airway distress, so proper diagnosis by the otorhinolaryngologist is critical to subsequent management. We present a retrospective review of 10 patients with the diagnosis of paradoxical vocal fold motion seen over a 6-year period. Eight patients were females, and 6 required an acute airway intervention at presentation; 3 patients eventually underwent tracheotomy for respiratory decompensation. Six patients had a prior diagnosis of asthma, and this was determined to contribute to their respiratory status. Five patients were treated with botulinum toxin and 2 with flexible nasolaryngoscopic biofeedback, which improved the outcome. A review of the literature confirms a female predominance of patients presenting with paradoxical adduction and airway distress, often with a history of asthma and psychopathology. Our experience with botulinum toxin and biofeedback suggests that these procedures are viable treatment options in the management of patients with this disorder.

Psychogenic Respiratory Distress: A Case of Paradoxical Vocal Cord Dysfunction and Literature Review

BACKGROUND: Pulmonary disease such as asthma is a psychosomatic disorder vulnerable to exacerbations precipitated by psychological factors. A case is described in which a patient thought to have treatment-refractory asthma was discovered to have a conversion reaction, specifically paradoxical vocal cord dysfunction (PVCD), characterized by abnormal vocal cord adduction during inspiration. DATA SOURCES: Reports of PVCD were located using a MEDLINE search and review of bibliographies. MEDLINE (English language only) was searched from 1966 through December 1998 using the terms functional asthma, functional upper airway obstruction, laryngeal diseases, Munchausen's stridor, paradoxical vocal cord dysfunction, psychogenic stridor, respiratory stridor, vocal cord dysfunction, and vocal cord paralysis. A total of 170 cases of PVCD were reviewed. STUDY FINDINGS: PVCD appears to be significantly more common among females. PVCD spans all age groups, including pediatric, adolescent, and adult patients. PVCD was most often misdiagnosed as asthma or upper airway disease. Because patients present with atypical and/or refractory symptoms, several diagnostic tests are employed to evaluate patients with PVCD; laryngoscopy is the most common. Direct visualization of abnormal vocal cord movement is the most definitive means of establishing the diagnosis of PVCD. A number of psychiatric disturbances are related to PVCD, including conversion and anxiety disorders. PVCD is associated with severe psychosocial stress and difficulties with modulation of intense emotional states. CONCLUSIONS: Psychogenic respiratory distress produced by PVCD can be easily misdiagnosed as severe or refractory asthma or other pulmonary disease states. Recognition of PVCD is important to avoid unnecessary medications and invasive treatments. Primary care physicians can detect cases of PVCD by attending to clinical symptoms, implementing appropriate laboratory investigations, and examining the psychological covariates of the disorder. Psychotherapy and speech therapy are effective in treating most cases of PVCD.

All that wheezes is not asthma. Paradoxical vocal cord movement presenting as severe acute asthma requiring ventilatory support

A 23-year-old female presented with an acute exacerbation of her asthma, for which she required ventilatory support. Her wheeze disappeared immediately following tracheal intubation and ventilatory support was achieved with low airway pressures. We believe that the diagnosis of status asthmaticus was incorrect and that the patient was suffering from vocal cord dysfunction. We review reports of this condition and suggest that, in asthma, the expiratory flow limitation due to paradoxical vocal cord movement may be an appropriate physiological response to improve overall airflow. However, this glottic narrowing may cause respiratory distress of its own accord. Our observations suggest a simple approach to the diagnosis and management of patients whose respiratory distress may be caused by paradoxical vocal cord movement. Immediate relief of 'bronchospasm' in an asthmatic following tracheal intubation may establish the correct diagnosis. This has important implications for the management of these patients in the intensive care unit.

Aryepiglottic fold: normal topography and clinical implications

The aryepiglottic folds extend between the arytenoid cartilage and the lateral margin of the epiglottis on each side and constitute the lateral borders of the laryngeal inlet. They are involved in physiologic closure mechanisms of the larynx and in pathologic conditions such as inspiratory stridor. Information on the normal topography of the aryepiglottic folds is poor and controversial. Therefore, this region was reinvestigated in serial whole-organ sections of 25 plastinated normal adult human larynges. Dorsally, the right and the left aryepiglottic folds are separated by the interarytenoid notch and comprise the corniculate and cuneiform cartilages, as well as numerous groups of mucous glands. Ventrally, the aryepiglottic folds are adjacent to the peri-epiglottic adipose tissue. Both regions are clearly separated by several layers of transversely oriented collagenous fiber layers. The muscular constituent of the aryepiglottic folds is only poorly developed, and no muscle fibers insert at the epiglottis. A coherent quadrangular membrane representing a ligamentous "skeleton" of the aryepiglottic folds is absent. A conspicuous collagenous fiber layer is found only to strengthen the free dorsal margin of the fold. Both muscular and ligamentous components may render the aryepiglottic folds sufficiently tense as to resist inspiratory inward suction in normal cases. However, pliability must be preserved to guarantee adequate folding in approximation of the aryepiglottic folds during deglutition. Thereby, the posterior part of the laryngeal inlet is closed, whereas the anterior part is probably closed by independent inward bulging of the peri-epiglottic adipose tissue.

Vocal cord dysfunction in three children--misdiagnosis of bronchial asthma?

Vocal cord dysfunction (VCD) is a paradoxical function of the vocal cords, leading to intermittent predominantly inspiratory dyspnea, but with no response to bronchodilator and anti-inflammatory drug therapy. We report on three children with VCD: 1) A 12-year old boy, who was treated for many years for bronchial asthma and who presented with inspiratory dyspnea and a functional reduction of the inspiratory and expiratory flow-volume curve, 2) a 13-year old girl who was also treated for bronchial asthma on a long-term basis and in whom the paradoxical vocal cord movement could be demonstrated by laryngoscopy, and 3) a 17-year old girl who, besides clinical symptoms of bronchial asthma in her anamnesis, suffered from an intermittent severe inspiratory dyspnea, refractory to bronchodilator treatment. Laryngoscopy proved the diagnosis of VCD. No patient showed a deterioration on discontinuation of their antiasthmatic therapy. VCD is best diagnosed by assessment of the vocal cords during laryngoscopy. The following therapeutic measures are helpful: 1) Demonstration of diagnosis (e.g. videodocumentation of laryngoscopy) and reassurance of patients and parents, 2) speech therapy, and 3) psychological intervention and/or psychotherapy. Our three cases point to a differential diagnosis of recurrent dyspnea in children and adolescents which may be overlooked. It is important to question earlier diagnoses, and to objectively evaluate the type of dyspnea.