Laryngoscopy during swimming: A novel diagnostic technique to characterize swimming-induced laryngeal obstruction

Epiglottic retraction is useful in diagnosis of exercise-induced laryngeal obstruction

Background: Exercise-induced laryngeal obstruction (EILO) is distinguished as upper airway obstruction accompanied by inspiratory dyspnoea and stridor during highly intensive exercises. Epiglottic retraction in the diagnosis of EILO has not been sufficiently explored. Aims/objectives: We highlight the importance of epiglottic retraction in patients with EILO by evaluation by several diagnostic methods for EILO. Consideration of epiglottic retraction may be important for accurate diagnosis of EILO. Results: Epiglottic retraction could be observed in three patients by laryngoscopy during heavy breathing and in two patients by continuous laryngoscopy during exercise. Stridor occurred by the forward prolapse of the arytenoids, but not by epiglottic retraction. In comparison with three athletes from other sports, lung volume was significantly greater in four swimmers although it was not different related to depending on the existence of epiglottic retraction. Conclusions and significance: Laryngoscopy during heavy breathing is suggested to be useful to detect the epiglottic retraction, which might be overlooked if only continuous laryngoscopy during exercise is used. Epiglottic retraction was not rare in Japanese swimmers' exercise-induced laryngeal obstruction in our cohort and it might be related to the greater lung volume.

The continuous laryngoscopy exercise test in severe or in difficult-to-treat asthma in adults: a systematic review

OBJECTIVE

A systematic review was performed to determine if the continuous laryngoscopy exercise test (CLE) has been used in the diagnostics of exercise dyspnea in adults with asthma, and whether inducible laryngeal obstruction (ILO) is found in those with asthma or with severe or difficult-to-treat asthma.

DATA SOURCES

We used Scopus and PubMed databases. The articles published up to 13 August 2019 were considered.

STUDY SELECTIONS

We excluded manuscripts that did not contain information about adult patients with asthma. We included six studies from 59 search results in Scopus and none from the 17 search results in PubMed.

RESULTS

The articles included 455 study individuals. Of these, 229 (50.3%) had diagnosed asthma or were treated with asthma medication. Altogether 31/229 (13.5%) subjects with diagnosis of asthma or previous asthma treatment had exercise-induced laryngeal obstruction (EILO) as comorbidity. The CLE test was performed on 229 patients with asthma. The method was used only for differential diagnosis of exercise-induced dyspnea to confirm EILO. At least 10/455 (2.2%) out of the 455 subjects experienced adverse events.

CONCLUSIONS

This systematic review revealed that only a small proportion of patients with asthma had undergone the CLE test to assess exercise-induced dyspnea. None of the selected manuscripts reported severity of asthma. Whether CLE provides a valuable diagnostic tool for patients with severe or difficult-to-treat asthma cannot be determined according to this review.

Diagnosis and management of allergy and respiratory disorders in sport: An EAACI task force position paper

Allergy and respiratory disorders are common in young athletic individuals. In the context of elite sport, it is essential to secure an accurate diagnosis in order to optimize health and performance. It is also important, however, to consider the potential impact or consequences of these disorders, in recreationally active individuals engaging in structured exercise and/or physical activity to maintain health and well-being across the lifespan. This EAACI Task Force was therefore established, to develop an up-to-date, research-informed position paper, detailing the optimal approach to the diagnosis and management of common exercise-related allergic and respiratory conditions. The recommendations are informed by a multidisciplinary panel of experts including allergists, pulmonologists, physiologists and sports physicians. The report is structured as a concise, practically focussed document, incorporating diagnostic and treatment algorithms, to provide a source of reference to aid clinical decision-making. Throughout, we signpost relevant learning resources to consolidate knowledge and understanding and conclude by highlighting future research priorities and unmet needs.

Exercise-induced laryngeal obstruction (EILO) in athletes: a narrative review by a subgroup of the IOC Consensus on 'acute respiratory illness in the athlete'

Exercise-induced laryngeal obstruction (EILO) is caused by paradoxical inspiratory adduction of laryngeal structures during exercise. EILO is an important cause of upper airway dysfunction in young individuals and athletes, can impair exercise performance and mimic lower airway dysfunction, such as asthma and/or exercise-induced bronchoconstriction. Over the past two decades, there has been considerable progress in the recognition and assessment of EILO in sports medicine. EILO is a highly prevalent cause of unexplained dyspnoea and wheeze in athletes. The preferred diagnostic approach is continuous visualisation of the larynx (via laryngoscopy) during high-intensity exercise. Recent data suggest that EILO consists of different subtypes, possibly caused via different mechanisms. Several therapeutic interventions for EILO are now in widespread use, but to date, no randomised clinical trials have been performed to assess their efficacy or inform robust management strategies. The aim of this review is to provide a state-of-the-art overview of EILO and guidance for clinicians evaluating and treating suspected cases of EILO in athletes. Specifically, this review examines the pathophysiology of EILO, outlines a diagnostic approach and presents current therapeutic algorithms. The key unmet needs and future priorities for research in this area are also covered.

Functional Respiratory Disorders in Children

Functional respiratory disorders (FRDs) are those characterized by respiratory symptoms without anatomic or organic etiology. Clinicians caring for children encounter these disorders and should be familiar with diagnosis and treatment. FRDs encompass the habit cough syndrome and its variants, vocal cord dysfunction, hyperventilation disorders, functional dyspnea, and sighing syndrome. Failure to identify these disorders results in unnecessary testing and medication. This article reviews the clinical presentation, manifestation, and treatment of respiratory FRDs in children. How health care providers can successfully identify and treat these reversible conditions in the clinical setting is discussed.

Changes in pulmonary function and feasibility of portable continuous laryngoscopy during maximal uphill running

Objective

To evaluate changes in pulmonary function and feasibility of portable continuous laryngoscopy during maximal uphill running.

Methods

Healthy volunteers participated in an uphill race. Forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) were obtained before and 5 and 10 min after finishing the race. Capillary blood lactate concentration ([BLa^-]) and Borg score for perceived exertion were registered immediately after the race. One participant wore a portable video-laryngoscope during the race, and the video was assessed for technical performance.

Results

Twenty adult subjects participated with a mean (SD) age of 40.2 (9.7) years. Mean (SD) race duration and post-exercise [BLa^-] was 13.9 (2.3) min and 10.7 (2.1) mmol/L, respectively, and the median (range) Borg score for perceived exertion was 9 (5–10).

Mean percentage change (95% CI) 5 and 10 min post-exercise in FEV₁ were 6.9 (3.7 to 10.2) % and 5.9 (2.7 to 9.0) %, respectively, and in FVC 5.2 (2.3 to 8.1) % and 4.7 (1.6 to 7.9) %, respectively. The recorded video of the larynx was of good quality.

Conclusions

Maximal aerobic field exercise induced bronchodilatation in the majority of the healthy non-asthmatic participants. It is feasible to perform continuous video-laryngoscopy during heavy uphill exercise.

Exercise-Associated Dyspnea and Stridor: Thinking Beyond Asthma

Breathlessness during sport can be caused by various cardiorespiratory conditions, but when associated with stridor, usually arises from an upper airway etiology. The term exercise-induced laryngeal obstruction (EILO) is now used to describe the phenomenon of transient glottic closure occurring in association with physical activity. Exercise-related laryngeal closure is most commonly encountered in athletic individuals and likely affects between 5% and 7% of all young adults and adolescents. The diagnosis of EILO is not always straightforward because features can overlap with exercise-induced asthma/exercise-induced bronchoconstriction. EILO can therefore remain misdiagnosed for years, and most patients receive inappropriate asthma therapy. In contrast with asthma, EILO symptoms are usually most prominent at maximal exercise intensity and resolve quickly on exercise cessation. It is important to recognize that EILO and asthma can coexist in a proportion of athletes. The criterion standard test for diagnosing EILO is continuous laryngoscopy during exercise testing, although eucapnic voluntary hyperpnea testing has also been used. Various surgical or pharmacological interventions can be used to treat EILO, but first-line treatment is breathing technique work. Further research is needed to establish the optimal treatment algorithm, and more work is needed to increase awareness of this important clinical entity.

Surgical intervention for exercise-induced laryngeal obstruction: A UK perspective

OBJECTIVES

Exercise-induced laryngeal obstruction (EILO) is a prevalent cause of exertional breathlessness and wheeze in young individuals. Typically diagnosed using the continuous laryngoscopy during exercise (CLE) test, treatment is largely based on breathing retraining promoting improved laryngeal function. In some cases, these techniques fail to alleviate symptoms, and surgical intervention with supraglottoplasty can be valuable in the supraglottic form of EILO. Globally, there is currently limited experience utilizing a surgical approach to EILO, and data regarding the optimum surgical technique and published outcomes and complication rates are thus limited.

STUDY DESIGN

Retrospective observational case series.

METHODS

In this report, we describe our experience as the only UK center undertaking supraglottoplasty for EILO. We report the surgical outcome of 19 patients (n = 16 female), mean age, 29.6 ± 13.1 years, referred for surgery with moderate to severe supraglottic EILO. Follow-up clinic ± CLE was performed within 4 months (median = 6 weeks), and CLE scores were evaluated before and following surgery.

RESULTS

We found a beneficial effect of surgery on supraglottic CLE scores (median score reducing from 3/3 to 1/3 postoperatively [P < .05] overall) with 79% (n = 15) of patients reporting an improvement in their exercise capacity. One patient developed an apparent increased tendency for glottic-level EILO following surgery; however, no voice- or swallowing-related complications were encountered.

CONCLUSIONS

This study is the first to report the UK experience, surgical technique, and outcome for EILO surgery. The findings indicate that EILO surgery appears to be a safe and effective option for individuals with moderate to severe supraglottic-type EILO who have failed initial conservative treatment.

LEVEL OF EVIDENCE

5 Laryngoscope, 130:E667-E673, 2020.

Pediatric Dysfunctional Breathing: Proposed Components, Mechanisms, Diagnosis, and Management

Dysfunctional breathing (DB) is an overarching term describing deviations in the normal biomechanical patterns of breathing which have a significant impact on quality of life, performance and functioning. Whilst it occurs in both children and adults, this article focuses specifically on children. DB can be viewed as having two components; breathing pattern disorder (BPD) and inducible laryngeal obstruction (ILO). They can be considered in isolation, however, are intricately related and often co-exist. When both are suspected, we propose both BPD and ILO be investigated within an all-encompassing multi-disciplinary dysfunctional breathing clinic. The MDT clinic can diagnose DB through expert history taking and a choice of appropriate tests/examinations which may include spirometry, breathing pattern analysis, exercise testing and laryngoscopic examination. Use of the proposed algorithm presented in this article will aid decision making regarding choosing the most appropriate tests and understanding the diagnostic implications of these tests. The most common symptoms of DB are shortness of breath and chest discomfort, often during exercise. Patients with DB typically present with normal spirometry and an altered breathing pattern at rest which is amplified during exercise. In pediatric ILO, abnormalities of the upper airway such as cobblestoning are commonly seen followed by abnormal activity of the upper airway structures provoked by exercise. This may be associated with a varying degree of stridor. The symptoms, however, are often misdiagnosed as asthma and the picture can be further complicated by the common co-presentation of DB and asthma. Associated conditions such as asthma, extra-esophageal reflux, rhinitis, and allergy must be treated appropriately and well controlled before any directed therapy for DB can be started if therapy is to be successful. DB in pediatrics is commonly treated with a course of non-pharmaceutical therapy. The therapy is provided by an experienced physiotherapist, speech and language therapist or psychologist depending on the dominant features of the DB presentation (i.e., BPD or ILO in combination or in isolation) and some patients will benefit from input from more than one of these disciplines. An individualized treatment program based on expert assessment and personalized goals will result in a return to normal function with reoccurrence being rare.

Exercise Induced Laryngeal Obstruction in Humans and Equines. A Comparative Review

Dynamic obstructions of the larynx are a set of disorders that occur during exercise in equines and humans. There are a number of similarities in presentation, diagnosis, pathophysiology and treatment. Both equines and humans present with exercise intolerance secondary to dyspnea. During laryngoscopy at rest, the larynx appears to function normally. Abnormalities are only revealed during laryngoscopy at exercise, seemingly triggered by increased ventilatory demands, and quickly resolve after cessation of exercise. Lower airway disease (asthma being the most prevalent condition), cardiac disease and lack of fitness are the major differentials in both species. Laryngoscopic examination during exercise should be performed from rest to peak exertion to allow for a comprehensive diagnosis, including where the airway collapse begins, and thereafter how it progresses. Dynamic disorders with most visual similarity between humans and equines are: aryepiglottic fold collapse (both species); equine dynamic laryngeal collapse (DLC) relative to some forms of human combined supraglottic/glottic collapse; and epiglottic retroversion (both species). Quantitative grading techniques, such as airway pressure measurement, that have proven effective in veterinary research are currently being piloted in human studies. Conditions that appear visually similar are treated in comparable ways. The similarities of anatomy and certain types of dynamic collapse would suggest that the equine larynx provides a good model for human upper respiratory tract obstruction during exercise. Thus, close collaboration between veterinarians and medical personal may lead to further advancements in understanding pathophysiologic processes, and enhance the development of improved diagnostic tests and treatments that will benefit both species.

Assessing laryngeal function and hypersensitivity

The larynx is one of the most highly innervated organs in humans, adapted to simultaneously deliver several key respiratory functions including airway protection, swallowing and phonation. In some individuals the larynx can adopt a state that could be considered 'dysfunctional' or maladaptive; resulting in or contributing to a range of clinical disorders such as chronic refractory cough, inducible laryngeal obstruction (previously termed paradoxical vocal fold movement or vocal cord dysfunction), muscle tension dysphonia and globus pharyngeus. These disorders appear to display significant overlap in clinical symptomology and in many cases have features of concomitant or allied sensory dysfunction; often described as laryngeal hypersensitivity. The recognition and accurate assessment of both laryngeal dysfunction±hypersensitivity is important to ensure accurate diagnosis and effective delivery of targeted treatment and therapeutic monitoring. Accordingly, there is increasing in the methodologies proposed to assess laryngeal function. These range from simple questionnaires to targeted investigation(s), assessing both sensory function and the laryngeal motor response, under both resting and provoked situations. This review provides a brief overview of the current state of knowledge in the field of laryngeal dysfunction and hypersensitivity assessment.

Feasibility of portable continuous laryngoscopy during exercise testing

Exercise-induced laryngeal obstruction (EILO) is a prevalent and yet still under-recognised cause of exertional breathlessness [1]. The transient closure of the larynx, which develops during EILO, results in dyspnoea, cough, inspiratory wheeze (i.e. stridor) and tightness in the throat on physical exertion. It is estimated that EILO is present in 6% of adolescents and as many as one in four athletes with unexplained respiratory symptoms [1, 2]. Despite improved recognition over the past 5 years [3, 4], it remains frequently misdiagnosed and mistreated as asthma [2, 5].

Exercise-induced laryngeal obstruction (EILO) is a prevalent problem causing exertional breathlessness and wheeze. This report demonstrates the feasibility and safety of a diagnostic approach to EILO, using a portable laryngoscope during exercise.http://ow.ly/eM6L30njDst

Exercise-induced laryngeal obstruction in athletes treated with inspiratory muscle training

Background

Exercise-induced laryngeal obstruction (EILO) is common in athletes and presents with dyspnoea, chest tightness, inspiratory stridor and sometimes panic reactions. The evidence for conservative treatment is weak, but case reports suggest effects from inspiratory muscle training (IMT). We aimed to explore effects from IMT used in athletes with EILO.

Method

Twenty-eight athletes, mean age 16.4 years, diagnosed with EILO at our clinic, participated in a 6-week treatment programme, using a resistive flow-dependent IMT device (Respifit S). Four athletes competed at international level, 13 at national and 11 at regional levels. Video-recorded continuous transnasal flexible laryngoscopy was performed from rest to peak exercise (continuous laryngoscopy exercise (CLE) test) and scored before and 2–4 weeks after the training period. Ergospirometric variables were obtained from this CLE set-up. Lung function was measured according to guidelines. Symptom scores and demographic variables were obtained from a questionnaire.

Results

After the treatment period, symptoms had decreased in 22/28 (79%) participants. Mean overall CLE score had improved after treatment (p<0.001), with the scores becoming normal in five athletes but worse in two. Most of the improvement was explained by changes at the glottic laryngeal level (p=0.009). Ergospirometric variables revealed significantly higher peak minute ventilation explained by higher tidal volumes and were otherwise unchanged.

Conclusion

This explorative study underlines the heterogeneous treatment response of EILO and suggests that IMT may become an efficient conservative treatment tool in subgroups, possibly contributing to better control of the vocal folds. The signals from this study should be tested in future controlled interventional studies.

Exercise-Induced Laryngeal Obstruction: When Pediatric Exertional Dyspnea Does not Respond to Bronchodilators

Exertional dyspnea is a common complaint in general pediatric practice. While a high proportion of the general pediatric population has asthma, other diagnoses, including exercise-induced laryngeal obstruction should be considered, especially when asthma therapy is not sufficient to control symptoms. This review describes some of the key clinical features of exercised-induced laryngeal obstruction as well as preferred diagnostic and therapeutic approaches. Importantly, current diagnostic technology has considerably improved in the last decade at specialty centers. At the same time, infrastructure for clinical trials is emerging and there is not strong evidence to support specific therapies at the current time.

Working Towards a Common Transatlantic Approach for Evaluation of Exercise-Induced Laryngeal Obstruction

Exertional dyspnea can be a manifestation of dysfunction in a variety of organ systems. Exercise-induced laryngeal obstruction (EILO), a condition previously known as vocal cord dysfunction and paradoxic vocal fold motion, is defined as inappropriate, reversible narrowing of the larynx during vigorous exercise. EILO is usually characterized by typical symptoms, which nevertheless frequently are confused with those of other conditions, including asthma. Laryngoscopy performed as symptoms evolve from rest to peak exercise is pivotal in patient work-up. Moving forward, laryngoscopy findings that definitively characterize EILO need to be defined as do objective measures that can quantitate absolute laryngeal measurements during exercise.

Exercise-Induced Laryngeal Obstruction-An Overview

Exertional dyspnea is common in health and disease. Despite having known for centuries that breathlessness can arise from the larynx, exercise-induced laryngeal obstruction is a more prevalent condition than previously assumed. This article provides a brief overview of the history, epidemiology, and pathophysiology of exercise-induced laryngeal obstruction.

Ergospirometry with concurrent fibre optic laryngoscopy: a randomised crossover study

Background: Patients suffering from exercise-induced laryngeal obstruction (EILO) are subjected to several exhausting tests. We aimed to assess the feasibility of using a single test to obtain diagnostic measurements for maximum oxygen uptake (VO₂max) and exercise-induced laryngeal obstruction (EILO).

Methods: Patients referred to the outpatient respiratory clinic at the University Hospital of Bispebjerg, Copenhagen with exercise-induced dyspnoea were evaluated for inclusion over 13 months. Eligible patients were aged 18–43 years, had a known EILO diagnosis (moderate or severe) and were inactive (self-reported activity) with less than 3 hours activity per week. In randomised order, all participants (n = 11) underwent three tests: a VO₂max test with and without concurrent laryngoscopy. VO₂max and EILO values from the two testing methods were compared.

Findings: There was no difference in VO₂max measured by ergospirometry with and without simultaneous continuous laryngoscopy during exercise (CLE) testing (mean difference −22 ml O₂･min⁻¹; 95% CI −125 to 81 ml O₂･min⁻¹; P = 0.647). EILO scores obtained during the CLE testing on the treadmill versus CLE testing on the ergometer bike revealed identical supraglottic scores in nine of the 11 participants (82%) with substantial agreement between the two types of test (x = 0.71). Glottic scores were identical in six of the 11 (55%), showing moderate agreement between test types (x = 0.38).

Conclusions: Based on our findings in inactive individuals, ergospirometry with laryngoscopy is feasible and well tolerated, yielding measurements for maximal oxygen uptake comparable to those of standard bike ergospirometry. Likewise, measurements of supraglottic EILO are comparable to those of the standard treadmill CLE test.

Differentiating vocal cord dysfunction from asthma

Vocal cord dysfunction (VCD)-associated symptoms are not rare in pediatric patients. Dyspnea, wheezing, stridor, chest pain or tightness and throat discomfort are the most commonly encountered symptoms. They may occur either at rest or more commonly during exercise in patients with VCD, as well as in asthmatic subjects. The phase of respiration (inspiration rather than expiration), the location of the wheezing origin, the rapid resolution of symptoms, and the timing occurring in relation to exercise, when VCD is exercise induced, raise the suspicion of VCD in patients who may have been characterized as merely asthmatics and, most importantly, had not responded to the appropriate treatment. The gold standard method for the diagnosis of VCD is fiberoptic laryngoscopy, which may also identify concomitant laryngeal abnormalities other than VCD. However, as VCD is an intermittent phenomenon, the procedure should be performed while the patient is symptomatic. For this reason, challenges that induce VCD symptoms should be performed, such as exercise tests. Recently, for the evaluation of patients with exercise-induced VCD, continuous laryngoscopy during exercise (such as treadmill, bicycle ergometer, swimming) was used. A definite diagnosis of VCD is of importance, especially for those patients who have been erroneously characterized as asthmatics, without adequate response to treatment. In these cases, another therapeutic approach is necessary, which will depend on whether they suffer solely from VCD or from both conditions.

Validity and reliability of grade scoring in the diagnosis of exercise-induced laryngeal obstruction

The current gold-standard method for diagnosing exercise-induced laryngeal obstruction (EILO) is continuous laryngoscopy during exercise (CLE), with severity classified by a visual grade scoring system. We evaluated the precision of this approach, by evaluating test-retest reliability of CLE and both inter- and intra-rater variability. In this prospective case-control study, subjects completed four consecutive treadmill CLE tests under identical conditions. Laryngoscopic video recordings were anonymised and graded by three expert raters. 2 months following initial scoring, videos were re-randomised and rating repeated to assess intra-rater agreement. 20 subjects (16 cases and four controls) completed four CLE tests. The time to exhaustion increased by 30 s (95% CI 0.02-57.8, p<0.05) in the second CLE compared with the first test, but remained identical in the subsequent tests. Only one-third of subjects retained their initial diagnosis in the subsequent three tests. Inter-rater agreement on grade scores (weighted Cohen's ϰ) was 0.16-0.45, while intra-rater agreement ranged from 0.30 to 0.67. The CLE test is key in the diagnostic assessment of patients with EILO. However, the widely adopted visual grade scoring system does not appear to be a robust means for reliably classifying severity of EILO.