Continuous laryngoscopy exercise test: a method for visualizing laryngeal dysfunction during exercise

Congenital laryngomalacia is related to exercise-induced laryngeal obstruction in adolescence

OBJECTIVES

Congenital laryngomalacia (CLM) is the major cause of stridor in infants. Most cases are expected to resolve before 2 years of age, but long-term respiratory prospects are poorly described. We aimed to investigate if CLM was associated with altered laryngeal structure or function in later life.

METHODS

Twenty of 23 (87%) infants hospitalised at Haukeland University Hospital during 1990-2000 for CLM without comorbidities and matched controls were assessed at mean age 13 years. Past and current respiratory morbidity was recorded in a questionnaire, and spirometry performed according to standard quality criteria. Laryngoscopy was performed at rest and continuously throughout a maximal treadmill exercise test (continuous laryngoscopy exercise test (CLE-test)), and scored and classified in a blinded fashion according to preset criteria.

RESULTS

In the CLM group, laryngeal anatomy supporting CLM in infancy was described at rest in nine (45%) adolescents. Eleven (55%) reported breathing difficulties in relation to exercise, of whom 7 had similarities to CLM at rest and 10 had supraglottic obstruction during CLE-test. Overall, 6/20 had symptoms during exercise and similarities to CLM at rest and obstruction during CLE-test. In the control group, one adolescent reported breathing difficulty during exercise and two had laryngeal obstruction during CLE-test. The two groups differed significantly from each other regarding laryngoscopy scores, obtained at rest and during exercise (p=0.001 or less).

CONCLUSIONS

CLM had left footprints that increased the risk of later exercise-induced symptoms and laryngeal obstruction. The findings underline the heterogeneity of childhood respiratory disease and the importance of considering early life factors.

Underlying Mechanisms in Episodic Laryngeal Breathing Disorders

The study and management of episodic laryngeal breathing disorders (ELBD)—characterized by paradoxical laryngeal movement patterns and dyspnea—has traditionally focused on clinical presentation of these conditions. However, the underlying mechanisms driving these entities are largely unknown. This article provides a review of potential underlying mechanisms driving clinical expression in ELBD and suggests approaches to the future study of ELBD etiology.

Eucapnic voluntary hyperpnoea and exercise-induced vocal cord dysfunction

INTRODUCTION

Exercise-induced bronchoconstriction (EIB) is a common condition in endurance athletes. Exercise-induced vocal cord dysfunction (EIVCD) is a frequent confounder of EIB. The diagnosis of EIVCD may be challenging and can be missed as the problem is often intermittent and may only occur during intense exercise. Eucapnic voluntary hyperventilation (EVH) is the best test to detect EIB. This pilot study aimed to assess if EVH could be helpful in the diagnosis of EIVCD associated or not to EIB in athletes.

METHODS

A nasolaryngoscopy was performed during a 6 min EVH test, in 13 female athletes suspected to have VCD, aged 21±7 years. Image analysis was conducted by two Ear Nose and Throat surgeons in random order.

RESULTS

During the EVH, three athletes showed incomplete paradoxical vocal cords movement, without inspiratory stridor. However, 12 athletes showed marked supraglottic movement without inspiratory stridor. In two athletes, this supraglottic movement was severe, one showing a marked collapse of the epiglottis with an almost complete obstruction of the larynx by the arytenoid cartilage mucosa. In 3 of the 12 athletes with supraglottic movement, severe vibration of the mucosa covering the arytenoid cartilages was also observed.

CONCLUSIONS

EVH challenge in athletes can provide information on various types of glottic and supraglottic obstruction in reproducing laryngeal movements during hyperventilation. Our findings make us suggest that exercise induced upper airway obstructions should be named: Exercise-induced laryngeal obstruction (EILO). Then, EILO should be divided in three categories: supraglottic, glottic (EIVCD) and mixed (glottic and supraglottic) obstruction.

Comparison between two assessment methods for exercise-induced laryngeal obstructions

Exercise-induced laryngeal obstructions (E-ILOs) are important differential diagnoses to exercise-induced asthma and are diagnosed by the continuous laryngoscopy exercise (CLE) test. There are two different methods for evaluating the severity of E-ILOs using recordings from the CLE test; the CLE score and EILOMEA. The aim of this study was to investigate the consistency between these methods. Using their respective method, the developers of each method evaluated 60 laryngoscopic recordings from patients with different subtypes and various levels of severity of E-ILOs. The CLE score evaluates glottic and supraglottic obstructions on a 4-grade scale. EILOMEA uses software to calculate the obstruction severity on continuous scales from a still frame of the larynx during maximal obstruction giving three parameters reflecting glottic and supraglottic obstruction. The means of the EILOMEA measures differed significantly for CLE score 1 vs. 2 and 2 vs. 3, but not for 0 vs. 1 for glottic as well as supraglottic obstructions. The EILOMEA method does not distinguish between CLE score 0 and 1, but otherwise the methods correlate. Since previous studies have suggested that only CLE scores of 2 and 3 reflect a severity of E-ILOs of clinical importance, this lack of the EILOMEA method is not crucial for a correct medical evaluation.

Larynx during exercise: the unexplored bottleneck of the airways

Exercise-induced shortness of breath is not uncommon in otherwise healthy young people. Based on the presenting symptoms alone, it is challenging to distinguish exercise-induced asthma (EIA) from exercise-induced obstruction of central airways, sometimes leading to diagnostic errors and inadequate treatment. Central airway obstruction usually presents with exercise-induced inspiratory symptoms (EIIS) during ongoing exercise. EIIS tends to peak towards the end of an exercise session or immediately after its completion, contradicting symptoms of EIA typically peaking 3-15 min after the exercise has stopped. EIIS is usually associated with some form of laryngeal obstruction. Transnasal flexible laryngoscopy performed continuously throughout an incremental exercise test from rest to exhaustion or to intolerable symptoms is usually diagnostic, and also provides information that is important for further handling and treatment. Reflecting the complex anatomy and functional features of the larynx, exercise-induced laryngeal obstruction (EILO) appears to be a heterogeneous condition. Contradicting previous beliefs, recent literature suggests that laryngeal adduction in a majority of cases starts in supraglottic structures and that vocal cord adduction (VCD) most often occurs as a secondary phenomenon. However, EILO is poorly understood and more and better research is needed to unravel causal mechanisms. The evidence base for treatment of EILO is weak. Speech therapy, psychotherapy, biofeedback, muscle training, anticholinergic aerosols have all been applied, as has laser supraglottoplasty. Randomized controlled trials with well-defined and verifiable inclusion and success criteria are required to establish evidence-based treatment schemes.

ERS/ELS/ACCP 2013 international consensus conference nomenclature on inducible laryngeal obstructions

Individuals reporting episodes of breathing problems caused by re-occurring variable airflow obstructions in the larynx have been described in an increasing number of publications, with more than 40 different terms being used without consensus on definitions. This lack of an international consensus on nomenclature is a serious obstacle for the development of the area, as knowledge from different centres cannot be matched, pooled or readily utilised by others. Thus, an international Task Force has been created, led by the European Respiratory Society/European Laryngological Society/American College of Chest Physicians. This review describes the methods used to reach an international consensus on the subject and the resulting nomenclature, the 2013 international consensus conference nomenclature.

Inducible laryngeal obstruction during exercise: moving beyond vocal cords with new insights

Exercise as an important part of life for the health and wellness of children and adults. Inducible laryngeal obstruction (ILO) is a consensus term used to describe a group of disorders previously called vocal cord dysfunction, paradoxical vocal fold motion, and numerous other terms. Exercise-ILO can impair one's ability to exercise, can be confused with asthma, leading to unnecessary prescription of asthma controller and rescue medication, and results in increased healthcare resource utilization including (rarely) emergency care. It is characterized by episodic shortness of breath and noisy breathing that generally occurs at high work rates. The present diagnostic gold standard for all types of ILO is laryngoscopic visualization of inappropriate glottic or supraglottic movement resulting in airway narrowing during a spontaneous event or provocation challenge. A number of different behavioral techniques, including speech therapy, biofeedback, and cognitive-behavioral psychotherapy, may be appropriate to treat individual patients. A consensus nomenclature, which will allow for better characterization of patients, coupled with new diagnostic techniques, may further define the epidemiology and etiology of ILO as well as enable objective evaluation of therapeutic modalities.

Dynamic laryngeal narrowing during exercise: a mechanism for generating intrinsic PEEP in COPD?

INTRODUCTION

Patients with COPD commonly exhibit pursed-lip breathing during exercise, a strategy that, by increasing intrinsic positive end-expiratory pressure, may optimise lung mechanics and exercise tolerance. A similar role for laryngeal narrowing in modulating exercise airways resistance and the respiratory cycle volume-time course is postulated, yet remains unstudied in COPD. The aim of this study was to assess the characteristics of laryngeal narrowing and its role in exercise intolerance and dynamic hyperinflation in COPD.

METHODS

We studied 19 patients (n=8 mild-moderate; n=11 severe COPD) and healthy age and sex matched controls (n=11). Baseline physiological characteristics and clinical status were assessed prior to an incremental maximal cardiopulmonary exercise test with continuous laryngoscopy. Laryngeal narrowing measures were calculated at the glottic and supra-glottic aperture at rest and peak exercise.

RESULTS

At rest, expiratory laryngeal narrowing was pronounced at the glottic level in patients and related to FEV1 in the whole cohort (r=-0.71, p<0.001) and patients alone (r=-0.53, p=0.018). During exercise, glottic narrowing was inversely related to peak ventilation in all subjects (r=-0.55, p=0.0015) and patients (r=-0.71, p<0.001) and peak exercise tidal volume (r=-0.58, p=0.0062 and r=-0.55, p=0.0076, respectively). Exercise glottic narrowing was also inversely related to peak oxygen uptake (% predicted) in all subjects (r=-0.65, p<0.001) and patients considered alone (r=-0.58, p=0.014). Exercise inspiratory duty cycle was related to exercise glottic narrowing for all subjects (r=-0.69, p<0.001) and patients (r=-0.62, p<0.001).

CONCLUSIONS

Dynamic laryngeal narrowing during expiration is prevalent in patients with COPD and is related to disease severity, respiratory duty cycle and exercise capacity.

Getting to grips with 'dysfunctional breathing'

Dysfunctional breathing (DB) is common, frequently unrecognised and responsible for a substantial burden of morbidity. Previously lack of clarity in the use of the term and the use of multiple terms to describe the same condition has hampered our understanding. DB can be defined as an alteration in the normal biomechanical patterns of breathing that result in intermittent or chronic symptoms. It can be subdivided into thoracic and extra thoracic forms. Thoracic DB is characterised by breathing patterns involving relatively inefficient, excessive upper chest wall activity with or without accessory muscle activity. This is frequently associated with increased residual volume, frequent sighing and an irregular pattern of respiratory effort. It may be accompanied by true hyperventilation in the minority of subjects. Extra thoracic forms include paradoxical vocal cord dysfunction and the increasingly recognised supra-glottic 'laryngomalacia' commonly seen in young sportsmen and women. While the two forms would appear to be two discreet entities they often share common factors in aetiology and respond to similar interventions. Hence both forms are considered in this review which aims to generate a more coherent approach to understanding, diagnosing and treating these conditions.

Vocal cord dysfunction in bronchial asthma. A review article

INTRODUCTION

Vocal cord dysfunction (VCD) is a condition in which the larynx exhibits paradoxical vocal cord adduction during inspiration, resulting in extra-thoracic variable airway obstruction. It has been described as a mimic of asthma, and hence, many patients with VCD are diagnosed as difficult-to-treat asthma and suffer significant morbidity as such.

METHODS

In completing this review we searched the literature using the database from MEDLINE, PubMed, and the Cochrane library using the medical terms "vocal cord/vocal cord dysfunction and asthma".

RESULTS

During the last few decades, many publications have described many conditions that may cause or coexist with VCD. In addition, the association between asthma and VCD was recognized. In this narrative review we provide an overview of the current knowledge about VCD and, in particular its relationship to asthma. We also provide a pragmatic diagnostic algorithm and treatment options based on our collaborative multi-disciplinary management of patients attending a difficult to control asthma clinic.

CONCLUSION

Most VCD patients present with inadequately controlled asthma rather than the typical symptoms described in association with VCD. Careful diagnostic strategy as outlined in this review may be helpful in confirming the diagnosis.

Prevalence of exercise-induced bronchoconstriction and exercise-induced laryngeal obstruction in a general adolescent population

BACKGROUND

Exercise-induced respiratory symptoms are common among adolescents. Exercise is a known stimulus for transient narrowing of the airways, such as exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO). Our aim was to investigate the prevalence of EIB and EILO in a general population of adolescents.

METHODS

In this cross-sectional study, a questionnaire on exercise-induced dyspnoea was sent to all adolescents born in 1997 and 1998 in Uppsala, Sweden (n=3838). A random subsample of 146 adolescents (99 with self-reported exercise-induced dyspnoea and 47 without this condition) underwent standardised treadmill exercise tests for EIB and EILO. The exercise test for EIB was performed while breathing dry air; a positive test was defined as a decrease of ≥10% in FEV1 from baseline. EILO was investigated using continuous laryngoscopy during exercise.

RESULTS

The estimated prevalence of EIB and EILO in the total population was 19.2% and 5.7%, respectively. No gender differences were found. In adolescents with exercise-induced dyspnoea, 39.8% had EIB, 6% had EILO and 4.8% had both conditions. In this group, significantly more boys than girls had neither EIB nor EILO (64.7% vs 38.8%; p=0.026). There were no significant differences in body mass index, lung function, diagnosed asthma or medication between the participants with exercise-induced dyspnoea who had or did not have a positive EIB or EILO test result.

CONCLUSIONS

Both EIB and EILO are common causes of exercise-induced dyspnoea in adolescents. EILO is equally common among girls and boys and can coexist with EIB.

Dyspneic athlete

Breathing concerns in athletes are common and can be due to a wide variety of pathology. The most common etiologies are exercise-induced bronchoconstriction (EIB) and paradoxic vocal fold movement disorder (PVFMD). Although some patients may have both, PVFMD is often misdiagnosed as EIB, which can lead to unnecessary treatment. The history and physical exam are important to rule out life threatening pulmonary and cardiac causes as well as common conditions such as gastroesophageal reflux disease, sinusitis, and allergic etiologies. The history and physical exam have been shown to be not as vital in diagnosing EIB and PVFMD. Improvement in diagnostic testing with office base spirometry, bronchoprovocation testing, eucapnic voluntary hyperpnea (EVH) and video laryngoscopy are essential in properly diagnosing these conditions. Accurate diagnosis leads to proper management, which is essential to avoid unnecessary testing and save healthcare costs. Also important to the physician treating dyspnea in athletes is knowing regulations on medications, drug testing, and proper documentation needed for certain organizations. The differential diagnosis of dyspnea is broad and is not limited to EIB and PVFMD. Ruling out life threatening cardiac and pulmonary causes with a proper history, physical, and appropriate testing is essential. The purpose of this review is to highlight recent literature on the diagnosis and management of EIB and PVFMD as well as discuss other potential causes for dyspnea in the athlete.

[Exercise-induced vocal cord dysfunction in asthma: a new diagnostic method]

OBJECTIVE

Vocal cord dysfunction (VCD) is an under-recognized cause of dyspnea and is difficult to diagnose. The symptoms caused by exercise-induced VCD (IEVCD) often falsely suggest asthma, but there is sometimes a real association between the two diseases. The objective of this study was to evaluate a new, simple method for analyzing vocal cord behavior in the diagnosis of IEVCD, and to clarify the prevalence of IEVCD in an uncontrolled asthma population with unexplained exertional dyspnea.

METHODS

This single-center study was conducted prospectively between April 2012 and March 2013. The main inclusion criterion was uncontrolled asthma with unexplained dyspnea. The assessment included cardiopulmonary exercise testing and supraglottal laryngoscopy during exercise with measurement of the vocal cord-opening angle (VCOA). Data from 15 asthmatic patients were compared with those from 10 non-asthmatic dyspneic patients (controls) to define specific criteria for the endoscopic diagnosis of IEVCD.

RESULTS

Endoscopy during bicycle exercising was well tolerated. Normal value of inspiratory VCOA (itVCOA) was>49°. Values for the itVCOA were lower for asthmatics than for controls when exercising at 50% maximal power (52.8°±13.3° and 64.5°±8.3°, respectively). Four of the 15 asthmatics (26%) demonstrated IEVCD characterized with itVCOApeak of less than 49°.

CONCLUSION

Measurement of VCOA represents a new, simple method for obtaining objective data in the exploration of VCD. The prevalence of IEVCD in uncontrolled asthmatic patients is important (26% in our small sample). IEVCD is probably an under-diagnosed aggravating factor in asthma, and its diagnosis and management could avoid the therapeutic climbing in asthma. This method of analysis may help to accurately and objectively assess vocal cord dysfunction.

Lesson of the month: Rowing-induced laryngeal obstruction: a novel cause of exertional dyspnoea: characterised by direct laryngoscopy

Exercise-induced laryngeal obstruction (EILO) is a key differential diagnosis for unexplained dyspnoea in athletes. The gold standard means for diagnosis of EILO is direct laryngoscopy, performed continuously, while an athlete undertakes the specific sport that precipitates their symptoms. This report provides the first descriptions of rowing-associated EILO in two competitive rowers presenting with unexplained dyspnoea and cough. The report describes the methodology and safety of the use of continuous laryngoscopy in the context of maximal rowing ergometry and the use of this technique as a therapeutic tool to provide biofeedback.

Glottic configuration in patients with exercise-induced stridor: a new paradigm

OBJECTIVES/HYPOTHESIS

Paradoxical vocal fold motion and exercise-induced paradoxical vocal fold motion (EIPVFM) are two related conditions that do not have definitive diagnostic criteria. Much of the EIPVFM literature describes patients with characteristic physiologic findings of severe upper airway obstruction or obvious airflow limitation in the clinical context of exertional dyspnea with audible stridor. The objective of this study was to highlight a group of patients who demonstrate important clinical findings of EIPVFM (exertional dyspnea with audible stridor) without simultaneously definitive physiologic findings (mild glottic adduction and normal flow volume loops).

STUDY DESIGN

Retrospective medical record review.

METHODS

We reviewed the records of 150 patients who performed continuous laryngoscopy during exercise for inclusion in a case series. We excluded patients for technical (incomplete records) and physiologic (extremes of disease severity) reasons. Three blinded physicians (practicing in laryngology, pulmonology, and allergy/immunology) independently evaluated isolated audio tracks, video tracks, and flow volume loops of the remaining patients for the presence or absence of stridor, the glottic configuration, and the presence or absence of inspiratory limitation on exercise flow volume loops at peak work capacity.

RESULTS

Exercise laryngoscopy and flow volume loops were fully evaluated for 23 patients. Five patients with exertional dyspnea were unanimously described as having audible stridor, open glottic configuration, and normal flow volume loops.

CONCLUSIONS

EIPVFM can occur in the absence of widely recognized confirmatory physiologic measures. Improved quantitative metrics are needed to better characterize patients with EIPVFM.

LEVEL OF EVIDENCE

4.

High prevalence of exercise-induced laryngeal obstruction in athletes

INTRODUCTION

Unexplained respiratory symptoms reported by athletes are often incorrectly considered secondary to exercise-induced asthma. We hypothesized that this may be related to exercise-induced laryngeal obstruction (EILO). This study evaluates the prevalence of EILO in an unselected cohort of athletes.

METHODS

We retrospectively reviewed the prevalence of EILO in a cohort of athletes (n = 91) referred consecutively during a 2-yr period for asthma workup including continuous laryngoscopy during exercise (CLE) testing. We compared clinical characteristics and bronchial hyperreactivity between athletes with and without EILO.

RESULTS

Of 88 athletes who completed a full workup, 31 (35.2%) had EILO and 38 (43.2%) had a positive bronchoprovocation or bronchodilator reversibility test. The presence of inspiratory symptoms did not differentiate athletes with and without EILO. Sixty-one percent of athletes with EILO and negative bronchoprovocation and bronchodilator reversibility tests used regular asthma medication at referral.

CONCLUSIONS

In athletes with unexplained respiratory symptoms, EILO is an important differential diagnosis not discerned from other etiologies by clinical features. These findings have important implications for the assessment and management of athletes presenting with persistent respiratory symptoms despite asthma therapy.

Exercise-induced dyspnea is a problem among the general adolescent population

RATIONALE

Respiratory symptoms during exercise are common and might limit adolescents' ability to take part in physical activity.

OBJECTIVE

To estimate the prevalence, determinants and consequences of exercise-induced dyspnea (EID) on daily life in a general population of 12-13 year old adolescents.

METHODS

A letter was sent to the parents of all 12-13 year old adolescents in the city of Uppsala (n = 3838). Parents were asked to complete a questionnaire together with their child on EID, asthma and allergy, consequences for daily life (wheeze, day time- and nocturnal dyspnea) and physical activity. The response rate was 60% (n = 2309).

RESULTS

Fourteen percent (n = 330) reported EID, i.e. had experienced an attack of shortness of breath that occurred after strenuous activity within the last 12 months. Female gender, ever-asthma and rhinitis were independently associated with an increased risk of EID. Ever-asthma was reported by 14.6% (n = 338), and 5.4% (n = 128) had both EID and ever-asthma. Sixty-one percent (n = 202) of the participants with EID did not have a diagnosis of asthma. In addition to rhinitis, participants with EID reported current wheeze and day-time as well as nocturnal dyspnea more often than the group without EID. No difference was found in the level of physical activity between participants with and without EID.

CONCLUSION

Adolescents with undiagnosed exercise-induced dyspnea have respiratory symptoms and are affected in daily life but have the same level of physical activity as adolescents without exercise-induced respiratory symptoms.

Pediatric Exercise Stress Laryngoscopy following Laryngotracheoplasty

Objective

Exercise-induced airway obstruction in pediatric patients is a unique phenomenon with multiple potential etiologies. An accurate diagnosis can be challenging to establish in pediatric patients because they are frequently asymptomatic at rest. Exercise stress laryngoscopy (ESL) is a modality by which pediatric patients can be evaluated under physiologic conditions that produce their symptoms. The purpose of this study was to demonstrate (1) the diagnostic effectiveness of pediatric ESL and (2) the ability of ESL to guide treatment for “normal” and post–airway reconstruction patients with exercise intolerance.

Study Design

Case series with chart review.

Setting

Tertiary care children’s hospital.

Subjects and Methods

Patients undergoing ESL for exercise intolerance were reviewed. Demographics, surgical history, examination findings, and management recommendations were extracted.

Results

Thirty-seven patients (average age, 13.5 years; range, 5-21 years) were included. There were 14 male and 23 female patients. Airway abnormalities became evident in 56% of patients. Of these, 24% had focal supraglottic collapse, 43% had evidence of paradoxical vocal fold motion, 24% had combined supraglottic and glottic dysfunction, and 9% had distal airway abnormalities. Overall, 18 patients had changes in management after ESL. Twelve patients in this review had histories of laryngotracheoplasty with equivocal findings on operative bronchoscopy. Of these patients, 10 (83%) received focal diagnoses after ESL.

Conclusion

ESL is a contemporary modality by which complex patients with undiagnosed exercise intolerance can be effectively evaluated. ESL can be an important tool used to guide treatment in pediatric patients with exercise-induced dyspnea after airway reconstruction.

Paradoxic vocal fold movement disorder

Paradoxical Vocal Fold Movement Disorder (PVFMD) is a cause of dyspnea that can mimic or occur alongside asthma or other pulmonary disease. Treatment with Laryngeal Control Therapy is very effective once the entity is properly diagnosed and contributing comorbidities are managed appropriately. In understanding the etiology of PVFMD, focus has broadened beyond psychiatric factors alone to include the spectrum of laryngeal irritants (laryngopharyngeal reflux, allergic and sinus disease, sicca, and possibly obstructive sleep apnea). The following is a discussion of the history, terminology, epidemiology, diagnosis, comorbid conditions, and treatment of this entity.

Exercise-induced vocal cord dysfunction and exercise-induced laryngomalacia in children and adolescents: the same clinical syndrome?

BACKGROUND

Exercise-induced respiratory symptoms associated with paradoxical laryngeal motion are relatively common and often mistaken for asthma. Exercise-induced vocal cord dysfunction (VCD) and exercise-induced laryngomalacia (LM) have been described separately in the literature but have never been systematically compared.

OBJECTIVE

To compare subjects with a confirmed diagnosis of exercise-induced VCD or exercise-induced LM by performing a retrospective chart review of subjects who had symptoms provoked by a free running exercise challenge and documented concurrent paradoxical laryngeal motion.

METHODS

Demographic and clinical characteristics were analyzed in patients with confirmed paradoxical motion of the vocal cords (VCD) and those with paradoxical arytenoid motion without abnormal vocal cord movement (LM) during symptoms.

RESULTS

Sixty subjects with exercise-induced LM and 83 subjects with exercise-induced VCD were identified. Subjects with confirmed exercise-induced VCD were slightly older, had a higher body mass index, and higher grade point averages compared with subjects with exercise-induced LM without abnormal vocal cord movement. There were no differences in sex distribution, presenting symptoms, reported aggravating factors other than exercise, atopic status, confirmed bronchospasm during symptoms, mean number of asthma controller medications at time of evaluation, level of athletic competition, reported history of acid reflux, reported history of psychiatric disorders, baseline lung function, or lung function during symptoms. Most subjects were not "elite" athletes and did not have a history of anxiety or depression.

CONCLUSION

There were remarkably few differences between subjects with exercise-induced VCD and those with exercise-induced LM. Prospective controlled studies are needed to determine whether exercise-induced VCD and exercise-induced LM are in fact distinct syndromes.

Eucapnic voluntary hyperventilation in diagnosing exercise-induced laryngeal obstructions

Exercise-induced laryngeal obstructions (EILOs) cause exercise-related respiratory symptoms (ERRS) and are important differential diagnoses to exercise-induced asthma. The diagnostic method for EILOs includes provocation to induce the obstruction followed by a verification of the obstruction and the degree thereof. The objective of the present study was to examine if a eucapnic voluntary hyperventilation (EVH) test could induce laryngeal obstructions laryngoscopically identical in subtypes and development as seen during an exercise test. EVH and exercise testing with continuous laryngoscopy were performed during a screening of two national athletic teams (n = 67). The laryngoscopic recordings were examined for usability, abnormalities and maximal supraglottic and glottic obstruction using two currently available methods (Eilomea and CLE-score). The participants were asked questions on ERRS, and whether the symptoms experienced during each provocation matched those experienced during regular training. A total of 39 completed both tests. There were no significant differences in subtypes and development thereof, the experience of symptoms, and specificity and sensitivity between the methods. Significantly more recordings obtained during the exercise test were usable for evaluation primarily due to resilient mucus on the tip of the fiber-laryngoscope in the EVH test. Only recordings of six athletes from both provocation methods were usable for evaluation using the Eilomea method (high-quality demand). Amongst these, a linear correlation was found for the glottic obstruction. EVH tests can induce EILOs. However, the present test protocol needs adjustments to secure better visualisation of the larynx during provocation.

[Spirometry patterns in vocal cord dysfunction]

INTRODUCTION

Vocal cord dysfunction (VCD) is a rare disease characterized by a paradoxical closure of the vocal cords, usually in inspiration, that causes dyspnea and stridor. The spirometry pattern that is more often described is a plateau in the inspiratory curve, but it can be also found in the expiratory loop The aim of this study was to evaluate the most common spirometry characteristics of patients with VCD and, secondarily, to describe the clinical and demographic characteristics and the treatment of patients with a definitive diagnosis of this disease.

MATERIAL AND METHODS

A retrospective study was made of cases of VCD between 2000 and 2010. Diagnosis was considered definitive when a paradoxical closure of the vocal cords became clear on laryngoscopy. Exercise challenge on a treadmill was performed to produce symptoms. Demographic and clinical data were collected, and flow-volume curves were studied.

RESULTS

Of 36 suspected cases, VCD was confirmed in 11 (30.5%). The mean age was 13.5 years, 10 were female. Possible triggers were found in 5 patients. Six patients had a previous history of asthma. All patients had a plateau in the inspiratory curve, and 9 (81%) of them also in the expiratory loop. Only 4 patients had a ratio between maximum inspiratory and expiratory flows at 50% of forced vital capacity (MEF50%/MIF50%) > 2.2.

CONCLUSIONS

Although the most frequent spirometry pattern in VCD is a plateau in the inspiratory curve, a significant percentage of patients also have a plateau in the expiratory curve. This could invalidate the MEF50%/MIF50% ratio for the diagnosis of VCD.

Work-related laryngeal syndromes

PURPOSE OF REVIEW

This review summarizes recent literature regarding the association of nonorganic laryngeal dysfunction with occupational exposures. Laryngeal dysfunction may masquerade as asthma and is an important consideration in patients with work-associated respiratory symptoms.

RECENT FINDINGS

Although there is lack of consensus regarding clinical features, vocal cord dysfunction (VCD) is the most well appreciated form of nonorganic laryngeal dysfunction. There are significant gaps in the literature regarding the occupational epidemiology of laryngeal dysfunction, however, occupational exposures such as upper airway irritants may be associated with the onset of symptoms. Recurrent work-associated laryngeal dysfunction has been described in occupational groups including the military and professional athletes. Recent theories have considered that VCD may be a state of laryngeal hyperresponsiveness associated with both intrinsic and extrinsic factors.

SUMMARY

Laryngeal dysfunction is an important consideration in patients with work-associated respiratory symptoms. Clinicians should have a high index of suspicion, in particular, if symptoms are associated with exposure to a respiratory irritant. Situations of high psychological stress may also be associated with recurrent symptoms. There is a requirement for evidence-based guidelines for the diagnosis and management of laryngeal dysfunction, which should also address work-related factors.

Allergy and sports in children

Physical activity is beneficial for children with positive outcomes for mental and physical well-being. Allergic conditions unique to the sporting arena may serve as an impediment to participation in physical activity for allergic children. A common example is exercise-induced asthma; less common activity-related allergic conditions include food-dependent exercise-induced anaphylaxis, exercise-induced anaphylaxis, and exercise-induced urticaria. Allergic children may also be at risk of allergic reactions when exposed to allergens that are more commonly found in the sports environment, e.g., latex, sports drinks, and medications such as NSAIDs. Recent advances in our understanding of the patho-physiological and immunologic mechanisms that may account for these conditions have facilitated more effective and safer management strategies. There are also important immunologic lessons to be learnt with respect to specific physical factors that may result in diminished allergen tolerance; indeed, these lessons may facilitate safer allergen desensitisation regimens. The role of the immune system in exercise-induced immunoallergic syndromes, clinical aspects, and diagnostic and therapeutic approaches are discussed in this review.

Multidisciplinary approach to vocal cord dysfunction diagnosis and treatment in one session: a single institutional outcome study

OBJECTIVE

To determine whether the multidisciplinary approach to the management of vocal cord dysfunction (VCD), which combines patient education and behavioral intervention in the same session that VCD is diagnosed, provides long-term therapeutic benefits.

METHODS

Chart review and telephone interviews of patients treated for VCD at The Children's Hospital of Philadelphia were performed in this retrospective nonrandomized study. All forty patients diagnosed with VCD from October 2007 to April 2009 were included. Patients were evaluated with a multidisciplinary team approach, including speech therapy assessment, otolaryngology exam and flexible laryngoscopy. Patients with VCD were educated about their condition and instructed about breathing techniques in the same session.

RESULTS

Twenty-two patients were available for a phone interview. Mean age of patients was 13.4 ± 3.0 years. Sixteen patients were female. Mean number of clinic visits was 1.3 ± 0.8. Average time between phone interview and first clinical encounter was 14.0 ± 7.2 months. Compliance rate to demonstrate breathing exercises was 90.9%. Nineteen out of 22 patients (86.4%) reported improvement of their symptoms in frequency and/or severity. Six patients (27.3%) sought additional medical advice related to their respiratory symptoms. Twenty-one patients (95.5%) were able to maintain or increase their level of physical activity following clinic visit.

CONCLUSION

Combining the diagnostic encounter with multidisciplinary behavioral intervention in a single visit is an efficacious approach for the long-term management of VCD in the pediatric population.

Asthma in elite athletes

Asthma is frequently found among elite athletes performing endurance sports such as swimming, rowing and cross-country skiing. Although these athletes often report symptoms while exercising, they seldom have symptoms at rest. Moreover, compared with nonathletic asthmatic individuals, elite athletes have been shown to have a different distribution of airway inflammation and unequal response to bronchial provocative test. Elite athletes display signs of exercise-induced symptoms, for example, nonasthmatic inspiratory wheeze, vocal cord dysfunction and cardiac arrhythmias, which could limit their physical capacity. Elite athletes should undergo comprehensive assessment to confirm an asthma diagnosis and determine its degree of severity. Treatment should be as for any other asthmatic individual, including the use of β2-agonist, inhaled steroid as well as leukotriene-antagonist. It should, however, be noted that daily use of β-agonists could expose elite athletes to the risk of developing tolerance towards these drugs. Use of β2-agonist should be replaced with daily inhaled corticosteroid treatment, the most important treatment of exercise-induced asthma. All physicians treating asthma should be aware of the doping aspects. Systemic β2-agonist intake is strictly prohibited, whereas inhaled treatment is allowed in therapeutic doses when asthma is documented and dispensation has been granted when needed.

Asthma in elite athletes: pathogenesis, diagnosis, differential diagnoses, and treatment

Elite athletes have a high prevalence of asthma and exercise-induced bronchoconstriction. Although respiratory symptoms can be suggestive of asthma, the diagnosis of asthma in elite athletes cannot be based solely on the presence or absence of symptoms; diagnosis should be based on objective measurements, such as the eucapnic voluntary hyperpnea test or exercise test. When considering that not all respiratory symptoms are due to asthma, other diagnoses should be considered. Certain regulations apply to elite athletes who require asthma medication for asthma. Knowledge of these regulations is essential when treating elite athletes. This article is aimed at physicians who diagnose and treat athletes with respiratory symptoms. It focuses on the pathogenesis of asthma and exercise-induced bronchoconstriction in elite athletes and how the diagnosis can be made. Furthermore, treatment of elite athletes with asthma, anti-doping regulations, and differential diagnoses such as exercise-induced laryngomalacia are discussed.

Vocal cord dysfunction: an update

OBJECTIVES

To review the clinical manifestations of vocal cord dysfunction (VCD) and to discuss new developments in the diagnosis and treatment.

DATA SOURCES

PubMed searches were performed for articles published regarding presentation, pathogenesis, diagnosis, and treatment options of VCD using the keywords vocal cord dysfunction, pathogenesis, clinical features, diagnosis, and management.

STUDY SELECTION

Articles were selected based on their relevance to the topic of this review. The newest developments in VCD were defined by articles published in the past 8 years.

RESULTS

The exact cause and pathogenesis remain unclear, although laryngeal hyperresponsiveness likely plays a role in a subset of patients. Certain findings on spirometry are often interpreted to suggest VCD, but recent studies have had varying results on how useful these are in the diagnosis of VCD. Diagnosis is made by direct visualization of the adduction of the vocal cords via rhinolaryngoscopy, but the method used to provoke symptoms and adduction varies. Other noninvasive tests have been evaluated as well.

CONCLUSION

The early recognition and treatment of VCD are imperative to prevent the misdiagnosis and mismanagement of asthma. In addition, VCD and asthma can occur together. The origin and pathogenesis of VCD need to be better defined. More studies comparing the provocation methods during laryngoscopy may be helpful in further standardizing a diagnostic test. Further research is needed to determine whether other noninvasive tests are as effective in diagnosing VCD as laryngoscopy.

Exercise-induced laryngeal obstruction: natural history and effect of surgical treatment

The current follow-up study concerning the supraglottic type of exercise-induced laryngeal obstruction (EILO) was performed to reveal the natural history of supraglottic EILO and compare the symptoms, as well as the laryngeal function in conservatively versus surgically treated patients. A questionnaire-based survey was conducted 2-5 years after EILO was diagnosed by a continuous laryngoscopy exercise (CLE) test in 94 patients with a predominantly supraglottic obstruction. Seventy-one patients had been treated conservatively and 23 with laser supraglottoplasty. The questionnaire response rate was 70 and 100% in conservatively treated (CT) and surgically treated (ST) patients, respectively. A second CLE test was performed in 14 CT and 19 ST patients. A visual analogue scale on symptom severity indicated improvements in both the groups, i.e. mean values (± standard deviations) declined from 73 (20) to 53 (26) (P < 0.001) in the CT group and from 87 (26) to 25 (27) (P < 0.001) in the ST group. At follow-up, ST patients reported lower scores regarding current level of complaints, and higher ability to perform exercise, as well as to push themselves physically, all compared to CT patients (P < 0.001). CLE scores were normalized in 3 of 14 (21%) CT and 16 of 19 (84%) ST patients (Z = -3.6; P < 0.001). In conclusion, symptoms of EILO diagnosed in adolescents generally decreased during 2-5 years follow-up period but even more after the surgical treatment. Patients with supraglottic EILO may benefit from supraglottoplasty both as to laryngeal function and symptom relief.

Exercise-induced laryngeal obstructions: prevalence and symptoms in the general public

Respiratory difficulties caused by exercise-induced laryngeal obstructions (EILOs) are reported with increasing frequency. The aim of this study was to assess the prevalence and symptoms of EILOs and their relation to airway hyperresponsiveness (AHR). In total, 556 randomly selected youths in Copenhagen aged 14-24 years were invited over a 2-year period. The study included a mailed questionnaire and two visits: day 1 (an interview-based questionnaire, methacholine bronchial provocation test and physical exertion test); and day 2 [an exercise test with continuous laryngoscopic recordings (CLE test)]. The diagnosis of EILOs was based on the CLE test. In total, 237 answered the mailed questionnaire and 150 participated on day 1 whereof 98 participated on day 2 also. AHR was verified in 23 (4.1% of invitees) and EILOs in 42 (7.5% of invitees). Co-morbidity was verified in 6 cases (26.1% of verified AHR cases). No symptoms were found specific for either AHR or EILOs. The minimum prevalence of EILOs in this cohort was 7.5%. EILOs were verified in 26.1% of participants with AHR. Questionnaires could not differentiate between AHR and EILOs.

Diagnostic criteria for the classification of vocal cord dysfunction

Vocal cord dysfunction (VCD) is a syndrome characterized by paroxysms of glottic obstruction due to true vocal cord adduction resulting in symptoms such as dyspnea and noisy breathing. Since first described as a distinct clinical entity in 1983, VCD has inadvertently become a collective term for a variety of clinical presentations due to glottic disorders. Despite an increased understanding of laryngeal function over the past 25 years, VCD remains a poorly understood and characterized entity. Disparities in the literature regarding etiology, pathophysiology, and management may be due to the historic approach to this patient population. Additionally, disorders clearly not due to paroxysms of true vocal cord adduction, such as laryngomalacia, vocal cord paresis, and CNS causes, need to be differentiated from VCD. Although a psychologic origin for VCD has been established, gastroesophageal reflux disease (GERD), nonspecific airway irritants, and exercise have also been associated with intermittent laryngeal obstruction with dyspnea and noisy breathing. VCD has been repeatedly misdiagnosed as asthma; however, the relationship between asthma and VCD is elusive. There are numerous case reports on VCD, but there is a paucity of prospective studies. Following an in-depth review of the medical literature, this article examines the available retrospective and prospective evidence to present an approach for evaluation of VCD including: (1) evaluation of factors associated with VCD, (2) differential diagnosis of movement disorders of the upper airway, and (3) clinical, spirometric, and endoscopic criteria for the diagnosis.

Left vocal cord paralysis after extreme preterm birth, a new clinical scenario in adults

OBJECTIVE

The goal was to study the incidence and long-term consequences of left vocal cord paralysis (LVCP) after neonatal surgical treatment of patent ductus arteriosus (PDA) in a population-based cohort of adults who were born at gestational ages of ≤28 weeks or with birth weights of ≤1000 g in western Norway.

METHODS

Subjects with a history of neonatal PDA surgery were examined with transnasal flexible laryngoscopy, and those with LVCP were examined with continuous laryngoscopy during maximal treadmill exercise (continuous laryngoscopy exercise testing). All subjects underwent lung function testing, ergospirometry, and pulmonary high-resolution computed tomography. Symptoms were recorded with a questionnaire.

RESULTS

Forty-four (86%) of 51 eligible preterm infants participated in the study, 13 (26%) had a history of PDA surgery and 7 (54%) had LVCP, with the laryngeal appearances varying slightly. As a group, subjects with LVCP had significant airway obstruction, no decreases in aerobic capacity, and no obvious evidence of longstanding aspiration on high-resolution computed tomography scans. The continuous laryngoscopy exercise tests revealed increasing respiratory symptoms in parallel with increasing anteromedial collapse of the left aryepiglottic folds as the exercise load increased. Hoarseness and voice-related symptoms were the most typical complaints. Symptoms were attributed erroneously to other diseases for at least 2 subjects.

CONCLUSIONS

LVCP is not uncommon in young adults exposed to PDA surgery as preterm infants. The condition may be overlooked easily, and symptoms may be confused with those of other diseases. Laryngoscopy should be offered on the basis of liberal indications after PDA ligation.

Exercise-induced respiratory symptoms: an epidemic among adolescents

OBJECTIVE

To review the most important causes of exercise-induced respiratory symptoms in adolescents.

DATA SOURCES

Published English-language medical literature.

STUDY SELECTION

Primary literature and consensus publications relevant to the objective.

RESULTS

The diagnosis and treatment of exercise-induced asthma are well characterized. Other syndromes, such as exercise-induced vocal cord dysfunction, exercise-induced paradoxical arytenoid motion, and exercise-induced hyperventilation, are relatively common but so far are described primarily in uncontrolled case reports.

CONCLUSION

Controlled studies are necessary to define efficient diagnostic and treatment algorithms for young patients experiencing respiratory symptoms during exercise who do not respond to asthma treatment.

Vocal cord dysfunction, paradoxic vocal fold motion, or laryngomalacia? Our understanding requires an interdisciplinary approach

This article presents disorders of periodic occurrence of laryngeal obstruction (POLO) resulting in noisy breathing and dyspnea and a variety of secondary symptoms. Included in this classification are glottic disorders, such as paradoxic vocal fold movement and vocal cord dysfunction. The supraglottic disorder, termed, intermittent arytenoid region prolapse or laryngomalacia, is also reviewed. Three categories of POLO are defined as irritant, exertional, and psychological.

Exercise induced dyspnea in the young. Larynx as the bottleneck of the airways

BACKGROUND

Exercise induced asthma may symptomatically be difficult to differentiate from exercise related obstruction in the upper airways, sometimes leading to diagnostic confusion and inappropriate treatment. Larynx accounts for a significant fraction of total airway resistance, but its role as a limiting factor for airflow during exercise has been hampered by lack of diagnostic tools. We aimed to study laryngeal function in exercising humans by transnasal laryngoscopy.

METHODS

Continuous video recording of the larynx was performed in parallel with continuous film recording of the upper part of the body and recording of breath sounds in subjects running to respiratory distress or exhaustion on a treadmill.

RESULTS

A successful examination was obtained in 20 asymptomatic volunteers and 151 (91%) of 166 young patients with a history of inspiratory distress or stridor during exercise. At rest, six patients had abnormal laryngeal findings. During exercise, a moderate or severe adduction of laryngeal structures was observed in parallel with increasing inspiratory distress in 113 (75%) patients. In 109 of these, adduction started within supraglottic structures, followed by adduction of the vocal cords in 88. In four patients, laryngeal adduction started in the vocal cords, involving supraglottic structures secondarily in three.

CONCLUSION

Larynx can safely be studied throughout a maximum intensity exercise treadmill test. A characteristic laryngeal response pattern to exercise was visualised in a large proportion of patients with suspected upper airway obstruction. Laryngoscopy during ongoing symptoms is recommended for proper assessment of these patients.

Audiovisual assessment of exercise-induced laryngeal obstruction: reliability and validity of observations

Variable obstruction to airflow at the laryngeal level may cause respiratory distress during exercise. The Continuous Laryngoscopy Exercise (CLE)-test enables direct visualization of the larynx during ongoing exercise. The aims of this study were to establish a scoring system for laryngeal obstruction as visualized during the CLE-test as well as to assess reliability and validity of this scoring system. Continuous video recording of the larynx was performed in parallel with continuous video recording of the upper part of the body, and recording of breath sounds in 80 patients and 20 symptom-negative volunteers, running on a treadmill to respiratory maximal tolerable distress or exhaustion. Each participant scored the degree of symptoms during exercise. The scoring system contains four sub-scores, each graded from 0 to 3. Two independent laryngologists, blinded to clinical data, scored the video recordings of the larynx twice. The proportion of inter- and intra-observer agreement (equal scores) for each sub-score through these four sessions varied between 70 and 100% (weighted kappa values varied from 0.49 to 1.00 correspondingly). A positive correlation was found between CLE-test sum score and symptom score (rho = 0.75, P < 0.001). There was a significant difference in CLE-test sum score between patients (3.34 +/- 1.34) and volunteers (0.65 +/- 0.66) (P < 0.001). The single CLE-test sub-score that correlated most strongly with symptom score was glottic adduction at maximal effort (rho = 0.75, P < 0.001). The presented scoring system is reliable and valid, and we suggest that it can be used when laryngeal function during exercise is evaluated.

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.