Diagnostic criteria for the classification of vocal cord dysfunction

Biobehavioral approach to distinguishing panic symptoms from medical illness

Panic disorder is a common psychiatric diagnosis characterized by acute, distressing somatic symptoms that mimic medically-relevant symptoms. As a result, individuals with panic disorder overutilize personal and healthcare resources in an attempt to diagnose and treat physical symptoms that are often medically benign. A biobehavioral perspective on these symptoms is needed that integrates psychological and medical knowledge to avoid costly treatments and prolonged suffering. This narrative review examines six common somatic symptoms of panic attacks (non-cardiac chest pain, palpitations, dyspnea, dizziness, abdominal distress, and paresthesia), identified in the literature as the most severe, prevalent, or critical for differential diagnosis in somatic illness, including long COVID. We review somatic illnesses that are commonly comorbid or produce panic-like symptoms, their relevant risk factors, characteristics that assist in distinguishing them from panic, and treatment approaches that are typical for these conditions. Additionally, this review discusses key factors, including cultural considerations, to assist healthcare professionals in differentiating benign from medically relevant symptoms in panic sufferers.

Dysfunctional Breathing in Children: A Literature Review

Dysfunctional breathing (DB) describes a respiratory condition that is mainly characterized by abnormal breathing patterns, affecting both children and adults, often leading to intermittent or chronic complaints and influencing physiological, psychological, and social aspects. Some symptoms include breathlessness; dizziness; palpitations; and anxiety, while its classification lies in breathing pattern disorders and upper airway involvement. Its prevalence among the pediatric population varies with a female overrepresentation, while the existence of comorbidities in DB, such as asthma, gastro-esophageal reflux, nasal diseases, and anxiety/depression, frequently leads to misdiagnosis or underdiagnosis and complicates therapeutic approaches. The basic diagnostic tools involve a detailed history, physical examination, and procedures such as structured light plethysmography, cardiopulmonary exercise testing, and laryngoscopy when a laryngeal obstruction is present. The management of DB presumes a multidimensional approach encompassing breathing retraining, disease-specific advice through speech and language therapy in the presence of laryngeal obstruction, psychotherapy for fostering self-efficacy, and surgical therapy in a structural abnormality. The current review was developed to provide a summary of classifications of DB and epidemiological data concerning the pediatric population, comorbidities, diagnostic tools, and therapeutic approaches to enhance the comprehension and management of DB in children.

Clinical Characteristics and Impact of Inducible Laryngeal Obstruction in the UK National Registry

BACKGROUND

Inducible laryngeal obstruction (ILO) describes inappropriate laryngeal closure during respiration, with airflow obstruction occurring at the glottic and/or supraglottic level, leading to breathlessness.

OBJECTIVE

There is a paucity of data describing the demographics and impact of ILO. We aimed to report the clinical and demographic features of ILO in individuals entered prospectively in the UK national ILO registry.

METHODS

Data were entered into a Web-based registry from participants with endoscopically confirmed ILO who were attending four established UK-wide specialist ILO centers between March 2017 and November 2019. All patients provided written informed consent.

RESULTS

Data from 137 individuals were included. Most (87%) had inspiratory ILO and required provocation during endoscopy to induce symptoms. There was a female predominance (80%), mean age 47 years (SD, 15 years). The most common comorbidities included asthma (68%) and reflux (57%). Health care use was high: 88% had attended emergency health care with symptoms at least once in the previous 12 months and nearly half had been admitted to the hospital. A fifth had required admission to critical care owing to ILO symptoms. Patient morbidity was substantial; 64% reported impaired functional capacity (≥3 on the Medical Research Council Dyspnoea Scale) and a third stated that symptoms affected working capability.

CONCLUSION

We describe the first multicenter prospective characterization of individuals with endoscopically diagnosed ILO. Analysis of our multicenter data set identified ILO as associated with a high burden of morbidity and health care use, comparable to severe asthma. These data will support the development of health care resources in the future and guide research priorities.

Laryngeal Dysfunction Manifesting as Chronic Refractory Cough and Dyspnea: Laryngeal Physiology in Respiratory Health and Disease

TOPIC IMPORTANCE

Laryngeal dysfunction as a cause of chronic refractory cough (CRC) and episodic dyspnea is often missed, which results in unnecessary testing and delays in diagnosis. Understanding laryngeal roles in breathing and airway protection can help to appreciate the propensity to laryngeal dysfunction with aging, chronic lung disease, and sleep apnea.

REVIEW FINDINGS

The human larynx is a complex muscular structure that is responsible for multiple roles of breathing, vocalization, coughing, and swallowing. To undertake these activities, the larynx has a high density of sensory and motor innervation. In addition to common embryological origins with the pharynx and esophagus, with which many laryngeal activities are shared, somatomotor and autonomic pathways regulate emotional, cognitive, and complex motor sequence-planning activities within the larynx. Due to its unique location, the larynx is susceptible to infectious and gastroesophageal reflux-related insults. Couple this with key roles in regulation of airflow and mediation of airway protective reflexes, it is not surprising that neuropathic abnormalities and muscle dysfunction frequently develop. The expression of laryngeal dysfunction as hypersensitivity to mechanical, thermal, chemical, and other stimuli leads to exaggerated airway protective reflexes (laryngeal adductor reflex and cough reflex) manifesting as dyspnea and cough.

SUMMARY

Pulmonologists should incorporate assessment of laryngeal dysfunction during evaluation of CRC and dyspnea. Recognition of laryngeal hypersensitivity in patient with CRC can identify patients who may benefit from cough suppression therapies. Similarly, timely identification of inducible laryngeal obstruction may not only resolve episodic dyspnea but lessen the need for unnecessary testing and treatments.

Clinical Profiles of Children and Adolescents With Induced Laryngeal Obstruction (ILO) and Exercise Induced Laryngeal Obstruction (EILO)

PURPOSE

To compare clinical profiles of pediatric patients with Induced Laryngeal Obstruction (ILO), Exercise Induced Laryngeal Obstruction (EILO), and EILO with non-exertion related secondary triggers (EILO+).

METHODS

A retrospective observational cohort design was employed. Four-hundred and twenty-three patients <18 years of age were identified from the electronic medical record of a large children's hospital. All patients underwent evaluations with a laryngologist and speech-language pathologist and were diagnosed with EILO/ILO. Patients were divided into 3 groups based on dyspnea triggers reported in initial evaluations. Groups consisted of patients with EILO (N = 281), ILO (N = 30), and EILO+ (N = 112). Patient demographics, EILO/ILO symptoms, endoscopy findings, medical comorbidities, medical history, and EILO/ILO treatment information were extracted and compared across EILO/ILO subtypes.

RESULTS

Patients with EILO experienced higher rates of hyperventilation (P < .001), sore throat (P = .023), and chest pain (P = .003). Patients with ILO were significantly younger in age (P = .017) and presented with increased rates of nighttime symptoms (P < .001), globus sensation (P = .008), self-reported reflux symptoms (P = .023), and history of gastrointestinal conditions (P = .034). Patients with EILO+ were more likely to be female (P = .037) and presented with higher prevalence of anxiety (P = .003), ADHD (P = .004), chest tightness (P = .030), and cough (P < .001).

CONCLUSIONS

Patients with EILO, ILO, and EILO+ present with overlapping but unique clinical profiles. A prospective study is warranted to determine the etiology of these differences and clarify how the efficacy of EILO, ILO, and EILO+ treatment can be maximized.

LEVEL OF EVIDENCE

4.

Vocal cord dysfunction/inducible laryngeal obstruction cannot be diagnosed from symptoms

Vocal cord dysfunction/inducible laryngeal obstruction is highly variable. Standard clinical symptoms and questionnaires cannot predict laryngoscopic diagnosis in a "lung disease" population. https://bit.ly/3QUtsbB.

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Diagnosis of vocal cord dysfunction/inducible laryngeal obstruction: An International Delphi Consensus Study

BACKGROUND

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is characterized by breathing difficulties in association with excessive supraglottic or glottic laryngeal narrowing. The condition is common and can occur independently; however, it may also be comorbid with other disorders or mimic them. Presentations span multiple specialties and misdiagnosis or delayed diagnosis is commonplace. Group-consensus methods can efficiently generate internationally accepted diagnostic criteria and descriptions to increase clinical recognition, enhance clinical service availability, and catalyze research.

OBJECTIVES

We sought to establish consensus-based diagnostic criteria and methods for VCD/ILO.

METHODS

We performed a modified 2-round Delphi study between December 7, 2021, and March 14, 2022. The study was registered at ANZCTR (Australian New Zealand Clinical Trials Registry; ACTRN12621001520820p). In round 1, experts provided open-ended statements that were categorized, deduplicated, and amended for clarity. These were presented to experts for agreement ranking in round 2, with consensus defined as ≥70% agreement.

RESULTS

Both rounds were completed by 47 international experts. In round 1, 1102 qualitative responses were received. Of the 200 statements presented to experts across 2 rounds, 130 (65%) reached consensus. Results were discussed at 2 international subject-specific conferences in June 2022. Experts agreed on a diagnostic definition for VCD/ILO and endorsed the concept of VCD/ILO phenotypes and clinical descriptions. The panel agreed that laryngoscopy with provocation is the gold standard for diagnosis and that ≥50% laryngeal closure on inspiration or Maat grade ≥2 define abnormal laryngeal closure indicative of VCD/ILO.

CONCLUSIONS

This Delphi study reached consensus on multiple aspects of VCD/ILO diagnosis and can inform clinical practice and facilitate research.

Update on Clinical Characteristics of Upper Airway Dyspnea: A Mixed Methods Study

OBJECTIVES

Provide a mixed-methods update on clinical presentation of patients with upper airway dyspnea (UAD).

STUDY DESIGN

Prospective, multicenter, mixed-methods study.

METHODS

Data were collected from 30 patients presenting to two tertiary ENT clinics with a chief complaint of dyspnea. Exclusionary criteria included abnormal structural laryngeal findings, uncontrolled pulmonary disorders, and medical conditions affecting breathing. Objective data collected included laryngeal exam findings, patient-reported outcome measures and symptom questionnaires, medications, and psychological diagnoses. Patients were categorized into groups based on the chronic or episodic nature of their dyspnea symptoms for comparison. Qualitative data from these groups were collected and analyzed.

RESULTS

Laryngeal exams revealed the presence of supraglottic constriction at rest was 26.66% and with phonation 83.33%. Ninety-three percent of patients did not show inappropriate vocal fold motion or adduction. Significant correlations were found between Dyspnea Index (DI) scores and other subjective questionnaires including Voice Handicap Index-10 (r = 0.64, P value = 0.001), Eating Assessment Tool-10 (r = 0.50, P value = 0.004), Cough Severity Index (r = 0.47, P value = 0.008), Vocal Cord Dysfunction Questionnaire (r = 0.59, P value = 0.005), and Somatic Symptom Scale-8 (r = 0.41, P value = 0.021). However, no significant correlation was found between the State-Trait Anxiety Index and DI (r = 0.27, P value = 0.1353). Qualitative analyses identified similar, but non-identical themes for both chronic and episodic dyspnea.

CONCLUSIONS

Patients with symptoms of UAD also report other abnormal head and neck and global body symptoms. Most patients with complaints of UAD in this study did not have abnormal vocal fold movements on laryngoscopy. There were differences in qualitative analyses between the chronic and episodic dyspnea groups, but no differences in state or trait anxiety.

Vocal cord dysfunction/inducible laryngeal obstruction-2022 Melbourne Roundtable Report

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO), is a common condition characterized by breathlessness associated with inappropriate laryngeal narrowing. Important questions remain unresolved, and to improve collaboration and harmonization in the field, we convened an international Roundtable conference on VCD/ILO in Melbourne, Australia. The aims were to delineate a consistent approach to VCD/ILO diagnosis, appraise disease pathogenesis, outline current management and model(s) of care and identify key research questions. This report summarizes discussions, frames key questions and details recommendations. Participants discussed clinical, research and conceptual advances in the context of recent evidence. The condition presents in a heterogenous manner, and diagnosis is often delayed. Definitive diagnosis of VCD/ILO conventionally utilizes laryngoscopy demonstrating inspiratory vocal fold narrowing >50%. Computed tomography of the larynx is a new technology with potential for swift diagnosis that requires validation in clinical pathways. Disease pathogenesis and multimorbidity interactions are complex reflecting a multi-factorial, complex condition, with no single overarching disease mechanism. Currently there is no evidence-based standard of care since randomized trials for treatment are non-existent. Recent multidisciplinary models of care need to be clearly articulated and prospectively investigated. Patient impact and healthcare utilization can be formidable but have largely escaped inquiry and patient perspectives have not been explored. Roundtable participants expressed optimism as collective understanding of this complex condition evolves. The Melbourne VCD/ILO Roundtable 2022 identified clear priorities and future directions for this impactful condition.

Predictors of voice therapy efficacy in vocal cord dysfunction at a tertiary care center

OBJECTIVE

Vocal cord dysfunction is inappropriate adduction of vocal cords during inspiration that causes dyspnea and is commonly mistaken for exercise-induced asthma. To improve diagnostic accuracy, this study aims to identify demographics associated with vocal cord dysfunction and to determine their impact on the efficacy of voice therapy in improving vocal cord function.

STUDY DESIGN

Retrospective chart review.

SETTING

Single tertiary care institution between January 2015 and December 2021.

METHODS

184 patients who underwent voice therapy for vocal cord dysfunction were included. The primary outcome was patient self-reported percent improvement of symptoms. The secondary outcome was number of voice therapy treatments.

RESULTS

The mean duration of symptoms was 2 ± 3 years. The mean number of voice therapy treatments was 2.2 ± 1.5. Of the 107 (58.2 %) patients with documented perceived breathing improvement percentages recorded, the mean maximal percent improvement was 72.5 ± 21.5 %. Mean maximal percent improvement of symptoms increased with each voice therapy treatment (p = 0.01). This association remained significant when controlling for comorbid conditions such as allergic rhinitis with postnasal drip, anxiety, asthma, and gastroesophageal reflux disease in multivariate analysis (p = 0.005). Patients with asthma had significantly higher maximum percent breathing improvement compared to those without asthma (p = 0.026). Similarly, patients who played sports had significantly higher maximum percent breathing improvement compared to those who did not (p = 0.022).

CONCLUSION

Patient perceived breathing improvement with voice therapy is higher among those with concomitant asthma and those who play sports. Voice therapy is a safe and effective first line treatment of vocal cord dysfunction even when controlling for comorbid conditions.

Computed Tomography Imaging of the Larynx for Diagnosis of Vocal Cord Dysfunction

BACKGROUND: Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is characterized by breathlessness and often mimics or accompanies severe asthma. The disorder occurs intermittently, and the diagnosis is established by using laryngoscopy. Dynamic computed tomography (CT) imaging of the larynx at low-radiation doses has the potential to provide an alternative method to make the diagnosis of VCD/ILO. METHODS: We report two case series: in series A, laryngoscopy (diagnostic standard) and CT imaging of the larynx were each performed within 1 hour of each other (n=31), and in series B, the procedures were performed on separate days 4 to 6 weeks apart (n=72). Diagnosis of VCD/ILO by laryngoscopy used conventional criteria, and diagnosis by CT imaging was based on vocal cord narrowing in excess of a validated normal threshold. In each series, we evaluated the accuracy of CT imaging of the larynx to establish a diagnosis of VCD/ILO compared with laryngoscopy. RESULTS: In series A, the sensitivity of CT imaging of the larynx was 53.8%, and specificity was 88.9%; in series B, the sensitivity of CT imaging of the larynx was 76.2%, and specificity was 93.3%. At a disease prevalence of 30% (which was known to be the case in our clinic), the positive predictive value was 67.5% in series A and 83% in series B. Negative predictive values were 81.8% and 90.1% in series A and B, respectively, and false-positive rates were 11.1% and 6.7%. CONCLUSIONS: When the population prevalence was assumed to be 30%, low-dose CT imaging of the larynx detected VCD/ILO with negative predictive values greater than 80% in both series settings and agreed with each other within 9 percentage points. Positive predictive values for laryngeal CT imaging varied substantially between the settings of the two case series. (Supported by Monash Lung and Sleep Institute and Grant APP ID 1198362 and others.)

Vocal cord dysfunction/inducible laryngeal obstruction: novel diagnostics and therapeutics

INTRODUCTION

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is an important medical condition but understanding of the condition is imperfect. It occurs in healthy people but often co-exists with asthma. Models of VCD/ILO pathophysiology highlight predisposing factors rather than specific mechanisms and disease expression varies between people, which is seldom appreciated. Diagnosis is often delayed, and the treatment is not evidence based.

AREAS COVERED

A unified pathophysiological model and disease phenotypes have been proposed. Diagnosis is conventionally made by laryngoscopy during inspiration with vocal cord narrowing >50% Recently, dynamic CT larynx was shown to have high specificity (>80%) with potential as a noninvasive, swift, and quantifiable diagnostic modality. Treatment entails laryngeal retraining with speech pathology intervention and experimental therapies such as botulinum toxin injection. Multidisciplinary team (MDT) clinics are a novel innovation with demonstrated benefits including accurate diagnosis, selection of appropriate treatment, and reductions in oral corticosteroid exposure.

EXPERT OPINION

Delayed diagnosis of VCD/ILO is pervasive, often leading to detrimental treatments. Phenotypes require validation and CT larynx can reduce the necessity for laryngoscopy, thereby fast-tracking diagnosis. MDT clinics can optimize management. Randomized controlled trials are essential to validate speech pathology intervention and other treatment modalities and to establish international standards of care.

Diagnosis of vocal cord dysfunction / inducible laryngeal obstruction-A Delphi study protocol

INTRODUCTION

Currently there is no consistent and widely accepted approach to the diagnosis of vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO). Harmonised diagnostic methods are vital to enable optimal diagnosis, advance management and enable research. We aim to obtain consensus on how expert clinicians recognise and diagnose VCD/ILO.

METHODS AND ANALYSIS

Two-round modified Delphi, with workshop validation.

ETHICS AND DISSEMINATION

Institutional Board Review was obtained from the Monash Health Human Research Ethics Committee. The dissemination plan is for presentation and publication.

REGISTRATION DETAILS

Registered at Australia and New Zealand Clinical Trials Registry ACTRN12621001520820p.

"Psychological characteristics of functional respiratory disorders in children and adolescents-Pilot study"

BACKGROUND

Aim of our prospective, multicenter, nonrandomized study was to identify characteristic features and similarities of patients with functional respiratory disorders regarding socio-familial and behavioral aspects, in comparison with controls in a cross-sectional analysis using standardized psychological questionnaires. Furthermore, we investigated the longitudinal outcome of symptoms, effects of primary interventions and the stability of psychological traits 6 months after diagnosis and primary intervention.

METHODS

Initially, 106 patients (68 females, 27 males) and 58 controls (33 females, 25 males) were recruited for the study. Mean age was 12.6 years in patients and 11.9 years in controls.

RESULTS

The child behavior checklist (CBCL) showed significantly increased scores for anxious/depressed (p = 0.002) and schizoid/obsessive (p = 0.001) behavior in patients. A trend was evident for internalizing behavior (p = 0.009) and for a higher total score (p = 0.008). In the self-assessment youth self-report (YSR), there was a trend towards higher values for anxious/depressed behavior in patients (p = 0.06) and towards more externalizing behavior (p = 0.029) in the control group. After 6 months, 31% of the patients were free of symptoms, 42% had improved. For themselves, parents reported a decreased burden from 56% to 23% (p < 0.001) and decreased impairment from 57% to 30% (p < 0.008). For their children, parents reported a decrease from 45% to 16% (p < 0.0001) and from 74% to 37% (p < 0.0001), respectively. A longitudinal comparison from T1 to T2 showed no statistically significant changes in all three psychological questionnaires (CBCL, YSR, and SOMS-KJ).

CONCLUSIONS

In summary, we show that patients with functional respiratory disorders differ from healthy subjects, with internalizing behavior being a characteristic trait. The outcome in terms of symptoms, perceived psycho-familial burden and impairment after 6 months is encouraging. However, we are aware that our preliminary data offer thought-provoking impulses rather than firm findings.

Paroxysmal dyspnoea in asthma: Wheeze, ILO or dysfunctional breathing?

Paroxysms of dyspnoea in the general population are commonly reported and are frequently assumed to be asthma-related, especially if this diagnostic label has been previously applied. Often, this is not the case. Inducible Laryngeal Obstruction (ILO) and Dysfunctional Breathing (DB) are common comorbid conditions that go unrecognised in many difficult-to-treat asthmatics. On average, these patients have a delay in diagnosis of almost 5 years. This delay, along with ineffective, inappropriate escalation of asthma therapy, frequent hospital presentations for uncontrolled symptoms, and even intensive care admissions, magnifies patient morbidity and poor quality of life. ILO and DB have similar presentations and triggers to asthma. Differentiating between them can be challenging, especially in centres that do not have access to multidisciplinary subspecialty asthma services. Objectively confirming the diagnosis can likewise be challenging as symptoms fluctuate, and gold-standard investigations require extensive experience. This mini-review will summarise the clinical features of ILO and DB, with particular focus in the context of individuals treated for asthma. This narrative review will define each condition, highlight poignant aspects of the history and describe elements of the diagnostic pathway to gain objective confirmation.

The impact of a fast-track questionnaire in pediatric paradoxical vocal fold motion disorder (PVFMD)

OBJECTIVE

PVFMD is a frequent cause of dyspnea in the healthy adolescent. When PVFMD is suspected, the current standard of care includes referral to an otolaryngologist (ENT) prior to beginning laryngeal control therapy (LCT) with a speech language pathologist (SLP). We hypothesize that a "fast-track" screening questionnaire will improve time to treatment and decrease patient charges.

METHODS

Patients (n = 258, group 1) who received traditional referral and were evaluated in pediatric voice clinic with a diagnosis of PVFMD between 11/2013 and 11/2017 were identified and compared with 66 patients (group 2) from 10/2018 to 11/2019 who were prospectively studied and placed into a fast-tracked subgroup for LCT without preceding ENT evaluation if they scored 8/10 or higher on a designed screening questionnaire.

RESULTS

Female gender (group 1: 81%, group 2: 83%, p = 0.73) and median age (group 1:14 years IQR 4; group 2:14 years IQR 3, p = 0.83) were similar. The median duration from symptom onset to LCT was shorter for group 2 (group 1: 12 months, IQR 18; group 2: 8.5 months, IQR 8)(p = 0.02). Time from referral to LCT was shorter for group 2 at 3 weeks (IQR 3) compared to group 1 at 4 weeks (IQR 3.5, p < 0.01). The minimum single patient charge for group 1 was estimated at $5123 and $1649 for group 2, yielding a potential reduction of charges of over $3000.

CONCLUSION

Using a fast-track screening questionnaire for pediatric PVFMD patients significantly decreases the time to treatment without altering the response rate of LCT.

Long-term pulmonary sequelae in adolescents post-SARS-CoV-2 infection

RATIONALE

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes long-term pulmonary sequelae in adults, but little is known about pulmonary outcomes in pediatrics.

OBJECTIVE(S)

The aim of this study was to describe long-term subjective and objective pulmonary abnormalities after SARS-CoV-2 infection in pediatric populations.

METHODS

Single-center, retrospective cohort of patients seen in post-coronavirus disease 2019 (COVID-19) pulmonary clinic in 2021. Subjects evaluated had persistent pulmonary symptoms 4 weeks or more after initial infection. Clinical testing included a 6-min walk test (6MWT), chest X-ray, pre- and postbronchodilator spirometry, plethysmography, and diffusion capacity. Patients were followed 2-to-3-months after the initial visit with repeat testing. The primary outcome was the presence of abnormal pulmonary function testing. Secondary measures included variables associated with pulmonary outcomes.

RESULTS

Eighty-two adolescents were seen at a median of 3.5 months postinfection, with approximately 80% reporting two or more symptoms at clinic presentation (cough, chest pain, dyspnea at rest, and exertional dyspnea). At follow-up (~6.5 months) exertional dyspnea persisted for most (67%). Spirometry was normal in 77% of patients, but 31% had a positive bronchodilator response. No abnormalities were noted on plethysmography or diffusion capacity. Clinical phenotypes identified included inhaled corticosteroid responsiveness, paradoxical vocal fold motion disorder, deconditioning, and dysautonomia. Multivariable modeling demonstrated that obesity, anxiety, and resting dyspnea were associated with reduced 6MWT, while female sex and resting dyspnea were associated with higher Borg Dyspnea and Fatigues scores.

CONCLUSIONS

This is the largest study to date of pediatric patients with long-term pulmonary sequelae post-COVID-19. Identified clinical phenotypes and risk factors warrant further study and treatment.

Endoscopic aspects and associated factors in paradoxical vocal fold movement

INTRODUCTION

Paradoxical vocal fold movement (PVFM) is a respiratory disorder related to inadequate movement of vocal folds during inspiration or expiration. Its epidemiology and pathogenesis are unknown. The present study describes the standardization of the examination performed in our service and the main endoscopic changes found, evaluating the prevalence of PVFM in patients with suggestive symptoms and describing the association of PVFM with asthma and other diseases.

MATERIALS AND METHODS

Retrospective observational study of a series of cases over a 13-year period - adult patients referred for outpatient bronchoscopy due to suspected PVFM.

RESULTS

We analyzed 1131 laryngoscopies performed on patients referred for suspicion of PVFM from May 2006 to June 2019. Of these, 368 cases were excluded from the study. A total of 255 patients (33%) had a confirmed diagnosis of PVFM, 224 women (88%). The most frequent comorbidities found were asthma (62%), rhinitis (45%), gastro-oesophageal reflux disease (45%), obesity (24%), and psychiatric disorders (19%). Among the endoscopic findings concomitant with the diagnosis of PVDM, we highlight posterior laryngitis (71%), diseases of the nasal septum (18%), nasal polyps (7%).

DISCUSSION

Female sex is more affected. There are several associations with other diseases, the main one being asthma, followed by rhinitis and psychiatric disorders. Obesity appears as a comorbidity in 24% of patients, as does sleep apnoea in 13%. Posterior laryngitis was the most common endoscopic finding. PVFM is an underdiagnosed disease, little known as it is a rare entity that still needs prospective studies. Exam standardization is important.

Resting Respiratory Resistance in Female Teenage Athletes With and Without Exercise-Induced Laryngeal Obstruction

OBJECTIVE

Exercise-induced laryngeal obstruction (EILO) occurs with paradoxical vocal fold motion or supraglottic collapse during moderate to vigorous exercise. Previously, Gallena et al (2015) reported lower-than-normal inspiratory (Ri) and expiratory (Re) resistances during resting tidal breathing (RTB) in female teenage athletes with EILO. This study aimed to replicate that unexpected result.

METHOD

The Airflow Perturbation Device measured Ri and Re during three 1-minute trials of RTB in 16 teenage female athletes with EILO and 16 sex-, age-, and height-matched controls. Multiple linear regression examined group, age, height, and weight as predictors of Ri and Re.

RESULTS

Ri and Re tended to be lower in the EILO group than the control group [Ri: F(1,30) = 3.58, P = 0.068, d = 0.686; Re: F(1,30) = 3.28, P = 0.080, d = 0.640], but there was no statistically significant difference in the overall effect [F(2,29) = 1.75, P = 0.192]. After one outlier for Re from the EILO group and her matched control were removed, the overall difference was statistically significant, F(2,27) = 3.38, P = 0.049, with Re primarily contributing to the difference [Ri: F(1,28) = 3.66, P = 0.066, d = 0.719; Re: F(1,28) = 5.69, P = 0.024, d = 0.899].

CONCLUSION

These results did not replicate the robust differences found previously between Ri and Re during RTB in teenage girls with and without EILO, but the results trended in the same direction and met criterion for statistical significance once an outlier was removed from analysis. Overall, the observation that resting respiratory resistances were lower in most teenage girls with EILO suggests that reduced tone of the laryngeal and/or lower airways may predispose young athletes to EILO.

A case of vocal cord dysfunction in the emergency department

We describe the case of a 78-year-old woman admitted to our emergency department for an acute onset of severe dyspnoea with inspiratory wheezing-like sounds. She denied fever, cough, voice change and pain. She referred a similar but less severe episode occurred spontaneously one year before, with complete resolution in few minutes without sequelae. On examination upper airway obstruction was firstly excluded. She was initially treated as having asthma, without response. Parenteral high dose corticosteroids and antihistamines provided no benefit. Point-of-care-ultrasound resulted normal. Flexible laryngoscopy during the episode showed paradoxical vocal cord movement with adduction during both inspiration and expiration. This demonstrated that her dyspnoea was from Vocal Cord Dysfunction (VCD). VCD completely solved after administration of intravenous benzodiazepines.

Systematic review of the effectiveness of non-pharmacological interventions used to treat adults with inducible laryngeal obstruction

Introduction

Inducible laryngeal obstruction (ILO) describes transient laryngeal closure during respiration and can cause significant morbidity. Non-pharmacological behavioural therapy is the commonly cited treatment but efficacy is largely unknown.

Aim

To synthesise the current evidence base on the effectiveness of non-pharmacological interventions used to treat adults with ILO.

Methods

Electronic databases (Medline/Embase/CINAHL/PsycINFO/AMED/CENTRAL) were systematically searched, informed by a population, intervention, comparison, outcome framework. Two reviewers independently screened a representative sample, with lead-author completion due to excellent inter-rater reliability. Data was extracted using a predefined piloted form. Methodological quality was appraised (blindly by two reviewers) using the Joanna Briggs Institute Critical Appraisal Tools. A narrative synthesis was performed due to heterogeneity of studies (PROSPERO registration number: CRD42020213187).

Results

Initial searching identified 3359 records. Full-text screening occurred in 92 records and 14 studies, comprising 527 participants, were deemed eligible. All studies were low-level evidence (observational by design, with four case reports), with a high risk of bias; none contained control arms for comparison. Intervention description was inconsistently and poorly described but direction of effect was positive in 76% of outcomes measured. The majority of studies showed a reduction in symptom scores and improved direct laryngeal imaging post intervention; there was an overall reduction, 59.5%, in healthcare utilisation.

Discussion

The literature is in an embryonic state and lacks robust data to truly inform on the effectiveness of non-pharmacological interventions used to treat adults with ILO. However, positive signals in the synthesis performed support non-pharmacological treatment approaches and further development is warranted.

Keeping Pace with Adolescent Asthma: A Practical Approach to Optimizing Care

Known for their pre-occupation with body image, self-identity creation, peer acceptance, and risk-taking behaviors, adolescents with asthma face unique challenges. Asthma is a heterogeneous disease and accurate diagnosis requires assessment through detailed clinical history, examination, and objective tests. Diagnostic challenges exist as many adolescents can present with asthma-like symptoms but do not respond to asthma treatment and risk being mis-diagnosed. Under-recognition of asthma symptoms and denial of disease severity must also be addressed. The over-reliance on short-acting beta-agonists in the absence of anti-inflammatory therapy for asthma is now deemed unsafe. Adolescents with mild asthma benefit from symptom-driven treatment with combination inhaled corticosteroids (ICS) and long-acting beta-agonist (LABA) on an as-required basis. For those with moderate-to-persistent asthma requiring daily controller therapy, maintenance and reliever therapy using the same ICS-LABA controller simplifies treatment regimes, while serving to reduce exacerbation risk. A developmentally staged approach based on factors affecting asthma control in early, middle, and late adolescence enables better understanding of the individual's therapeutic needs. Biological, psychological, and social factors help formulate a risk assessment profile in adolescents with difficult-to-treat and severe asthma. Smoking increases risks of developing asthma symptoms, lung function deterioration, and asthma exacerbations. Morbidity associated with e-cigarettes or vaping calls for robust efforts towards smoking and vaping cessation and abstinence. As adolescents progress from child-centered to adult-oriented care, coordination and planning are required to improve their self-efficacy to ready them for transition. Frequent flare-ups of asthma can delay academic attainment and adversely affect social and physical development. In tandem with healthcare providers, community and schools can link up to help shoulder this burden, optimizing care for adolescents with asthma.

Clinical Findings among Patients with Respiratory Symptoms Related to Moisture Damage Exposure at the Workplace-The SAMDAW Study

BACKGROUND

Respiratory tract symptoms are associated with workplace moisture damage (MD). The focus of this observational clinical study was patients with workplace MD-associated symptoms, to evaluate the usefulness of different clinical tests in diagnostics in secondary healthcare with a special interest in improving the differential diagnostics between asthma and laryngeal dysfunction.

METHODS

In patients referred because of workplace MD-associated respiratory tract symptoms, we sought to systematically assess a wide variety of clinical findings.

RESULTS

New-onset asthma was diagnosed in 30% of the study patients. Laryngeal dysfunction was found in 28% and organic laryngeal changes in 22% of the patients, and these were common among patients both with and without asthma. Most of the patients (85%) reported a runny or stuffy nose, and 11% of them had chronic rhinosinusitis. Atopy was equally as common as in the general population.

CONCLUSIONS

As laryngeal changes were rather common, we recommend proper differential diagnostics with lung function testing and investigations of the larynx and its functioning, when necessary, in cases of prolonged workplace MD-associated symptoms. Chronic rhinosinusitis among these patients was not uncommon. Based on this study, allergy testing should not play a major role in the examination of these patients.

Economic Burden Associated With Management of Paradoxical Vocal Fold Motion Disorder

OBJECTIVES

Paradoxical vocal fold movement (PVFM) is often misdiagnosed as asthma and tends to have a prolonged time to diagnosis. Study aims were to estimate the time from dyspnea onset to PVFM diagnosis, to estimate associated pre- and postdiagnosis direct and indirect healthcare cost, and to compare the cost of postdiagnosis care among patients who did and did not undergo standard-of-care speech therapy.

METHODS

Patients diagnosed with PVFM were identified retrospectively. Time from dyspnea symptom onset to diagnosis was measured. Direct costs consisting of office visits, procedures, and prescribed pharmaceuticals before and after diagnosis were calculated. Indirect costs associated with lost wages related to healthcare were also estimated. Costs for patients who initiated versus did not initiate speech therapy and who had successful versus unsuccessful therapy were compared.

RESULTS

Among 110 patients, median time from dyspnea onset to PVFM diagnosis was 33 months (interquartile range [IQR] 5-60). Direct and indirect prediagnosis median costs were $8,625 (IQR $1,687-$35,812) and $736 (IQR $421-$1,579) while first year following dyspnea symptom onset median direct and indirect costs were $1,706 (IQR $427-$7,118) and $315 (IQR $131-$631). Median direct and indirect costs of care in the postdiagnosis year were $2,062 (IQR $760-$11,496) and $841 (IQR $631-$1,261). Pharmaceuticals were predominant cost drivers in all time periods. Of those who completed speech therapy, 85% had breathing symptom improvement while incurring significant cost savings compared to those whose symptoms persisted.

CONCLUSION

Costs of care leading to diagnosis of PVFM are substantial. More efficient methods of identifying patients with PVFM are essential to reduce prolonged time to diagnosis and associated costs.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2021.

Exercise-induced laryngeal obstruction in children and adolescents: are we listening?

Exertional dyspnoea among children and adolescents is a common presenting complaint to general practitioners. Exertional dyspnoea is most commonly attributed to exercise-induced bronchoconstriction (EIB), but there are several other causes including hyperventilation syndrome, breathlessness associated with normal exercise limitation and exercise-induced laryngeal obstruction (EILO). The symptoms of EILO include stridor, throat tightness and difficulty on inspiration. If these are mistaken for EIB, children will receive asthma therapy. The underlying mechanism of EILO includes closure of the larynx during high-intensity exercise, which causes a reduction in airflow and breathlessness. This phenomenon is often associated with a background of psychological stress. Historically, a diagnosis of EILO has been considered 'rare' though this may be a reflection of under-recognition. Direct visual observation via laryngoscopy is the gold standard for diagnosis of EILO; however, this is rarely available even in specialised centres. Nevertheless, the diagnosis can usually be made by recognising the characteristic clinical pattern. Here we provide recommendations for appropriate investigations for the determination of EILO, together with suggested treatment.

Visual biofeedback for paradoxical vocal fold motion (PVFM)

Objectives

Paradoxical vocal fold motion (PVFM) is a common condition where the vocal folds inappropriately adduct during inspiration. This results in dyspnea and occasionally significant distress. The condition is thought to be primarily functional, with behavioural therapy considered mainstay in the non-acute setting. However, practice variations and limited access to speech language pathology (SLP) services can pose management challenges. We aimed to examine the efficacy of surgeon performed visual biofeedback as first-line treatment for PVFM.

Study design

Prospective, non-randomized, non-comparative clinical study.

Methods

Adult patients referred for possible PVFM and congruent laryngoscopy findings over a two-year period were included. Patients were excluded if they presented in acute distress, had alternate diagnosis to explain symptomology and/or coexisting untreated lower respiratory pathology. Patients underwent immediate surgeon-performed visual biofeedback on the same visit day. The primary outcome of interest was change in Dyspnea Index (DI) scores pre- and post-intervention 3 months follow-up. The secondary outcome measured was change in asthma medication use from baseline to follow-up.

Results

Of 34 patients presenting, 25 met inclusion criteria. Of these, 72% were female with an average age of 36.9 ± 14.1. Approximately 48% of patients had a diagnosis of well-controlled asthma at presentation and co-morbid psychiatric diagnoses were common (52%). Pre- and post-intervention analysis showed significant improvement in DI scores (p < 0.001) and reduction in bronchodilator use (p = 0.003).

Conclusion

This is a prospective study that evaluates the role of visual biofeedback in PVFM patients. Our data suggests that visual biofeedback effectively reduces short-term subjective symptoms and asthma medication use.

Level of evidence

3

Graphical abstract

Reduced Asthma Medication Use after Treatment of Pediatric Paradoxical Vocal Fold Motion Disorder

OBJECTIVES/HYPOTHESES

The primary objective of this study was to determine whether the diagnosis and treatment of pediatric Paradoxical Vocal Fold Motion Disorder (PVFMD) leads to decreased asthma medication use. Our secondary objective was to determine dyspnea outcomes following diagnosis and treatment for PVFMD.

STUDY DESIGN

Prospective observational study.

METHODS

Patients with newly diagnosed PVFMD between the ages of 11 and 17 were recruited at a single pediatric institution. A medication questionnaire and Dyspnea Index (DI) were completed at the initial visit, at the first return visit, and at greater than 6 months post-diagnosis and therapy. Laryngeal Control Therapy (LCT) consisted of teaching breathing techniques and identifying emotional, physical, and environmental contributing factors and strategies to reduce them.

RESULTS

Twenty-six patients were recruited to the study. There were 19/26 (73%) patients diagnosed with asthma prior to a diagnosis of PVFMD, and 26/26 (100%) patients were using an inhaler prior to the enrollment visit. Twenty-two (85%) patients completed follow-up questionnaires. Five patients participated in no therapy, seven patients in partial therapy, and 14 patients in full therapy. Significant reduction in asthma medication use was seen in the full therapy group (P < .05) and in those with exercise as their only trigger (P < .05). Furthermore, symptoms as scored by the DI decreased overall from 25.5 to 18.8 (P < .001).

CONCLUSIONS

Diagnosis and treatment of pediatric PVFMD leads to a decline in asthma medication use in those patients who participate in at least two LCT sessions and in those with exercise-induced PVFMD. LCT for pediatric PVFMD leads to a significant decrease in symptoms as measured by the DI.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1639-1646, 2021.

Obstructive Sleep Apnea with Paradoxical Vocal Cord Movement in Children during Sleep Endoscopy: Case Series

Objective

To describe a series of pediatric cases of obstructive sleep apnea (OSA) with paradoxical vocal cord movement noted on drug-induced sleep endoscopy (DISE).

Materials and Methods

Case series and chart review of children who had undergone DISE for OSA that showed PVCM.

Results

Three cases where paradoxical vocal cord motion (PVCM) was noted during DISE are described. Two had an enlarged adenoid, and one had no other site of obstruction. Two were treated with adenoidectomy and antireflux medications. One received proton pump inhibitors alone. In all 3 cases, OSA symptoms resolved.

Conclusion

This case series of documented obstructive sleep apnea related to paradoxical vocal cord movement suggests that this entity occurs during sleep with airway obstruction. Further clarification of etiology of PVCM during OSA and its management is needed.

Paroxysmal Laryngospasm: A Rare Condition That Respiratory Physicians Must Distinguish from Other Diseases with a Chief Complaint of Dyspnea

Background

In recent years, we have observed respiratory difficulty manifested as paroxysmal laryngospasm in a few outpatients, most of whom were first encountered in a respiratory clinic. We therefore explored how to identify and address paroxysmal laryngospasm from the perspective of respiratory physicians.

Methods

The symptoms, characteristics, auxiliary examination results, treatment, and prognosis of 12 patients with paroxysmal laryngospasm treated in our hospital from June 2017 to October 2019 were analyzed.

Results

Five males (42%) and 7 females (58%) were among the 12 Han patients sampled. The average age of the patients was 49.25 ± 13.02 years. The disease course ranged from 14 days to 8 years and was characterized by sudden dyspnea, an inability to inhale and exhale, a sense of asphyxia, and voice loss during an attack. Eight patients with gastroesophageal reflux were cured after antacid treatment. One case of upper respiratory tract infection (URI) was completely relieved after symptomatic treatment. One patient with left vocal cord paralysis experienced complete relief after specialist treatment by an otorhinolaryngologist. Episodes in 1 patient were significantly reduced after lifestyle improvement. One patient experienced spontaneous relief after rejecting treatment.

Conclusions

Paroxysmal laryngospasm is a rare laryngeal disease that generally occurs secondary to gastroesophageal reflux disease (GERD), and antireflux therapy is frequently effective for its treatment. A respiratory physician should master and identify the symptoms and differentiate this condition from hysterical stridor, reflux-related laryngospasm, and asthma. Timely referral to otolaryngologists, gastroenterologists, and other specialists for standardized examination and regular treatment should be provided when necessary.

Breathing pattern disorders (dysfunctional breathing) characteristics and outcomes of children and young people attending a secondary care respiratory clinic

METHODS

We retrospectively audited the health records of 18 patients with breathing pattern disorders (BPDs), who were diagnosed in our respiratory clinic (2015-2018), and then referred onto our dysfunctional breathing care pathway to a specialist speech and language therapist.

RESULTS

The age of the patients ranged from 11 to 16 years (median: 14 years, 14 female/4 male patients). Comorbidities included the following: 16 patients had asthma, 2 patients had a tracheoesophageal fistula and esophageal atresia repair, one patient suffered from chronic regional pain syndrome, and one patient had chronic fatigue syndrome. The commonest BPD was induced laryngeal obstruction (ILO) in 16 patients (exercise-induced laryngeal obstruction [EILO] in 15). Other types of BPDs included hyperventilation syndrome in seven patients, psychogenic cough in eight, and dysphonia in one. A single BPD was present in 6 patients (mainly EILO), and two or more BPDs were present in 10 patients. Inducers of BPD symptoms were as follows: exercise in 16 patients, bullying in 3, anxiety in 14, emotions and stress in 11, weather in 3, posture in 1, and odors in 3. Significant school absenteeism was observed in most of the patients (2 weeks to 24 months). Significant delays in diagnosing BPD were noted (range: 1-24 months and median: 6 months). Emergency calls occurred in 14 patients, with one patient presenting with ILO and comorbidity of asthma needing intubation and ventilation. A 1-year follow-up of patients showed that there was a complete resolution of BPD in two patients, 14 had good control of BPD with confidence in ability to control their symptoms, showing improved morbidity, two had no improvement, and one lost to follow-up.

CONCLUSION

It is important to recognize and treat BPD early to limit the significant morbidity that adversely impacts the quality of life.

Outcomes of Paradoxical Vocal Cord Motion Diagnosed in Childhood

OBJECTIVES

To explore long-term patient reported outcome (PRO) measures of pediatric paradoxical vocal cord motion (PVCM) including ease of diagnosis, management, symptom duration and effect on quality of life.

METHODS

All children >8 years of age diagnosed with PVCM at a tertiary pediatric hospital between 2006 and 2017 were invited to complete a survey addressing study objectives.

RESULTS

21/47 eligible participants could be contacted and 18/21 (86%) participated. 78% were female with a mean age at diagnosis of 11.6 and 15.0 years at survey completion. Common PVCM symptoms reported were dyspnea (89%), globus sensation (56%), and stridor (50%). The median time to diagnosis was 3 months (IQR 2-5 months). Nearly all reported being misdiagnosed with another condition, usually asthma, until being correctly diagnosed usually by an otolaryngologist. Participants reported undergoing 3.7 diagnostic studies (range 0-8); pulmonary function testing was most common. Of numerous treatments acknowledged, breathing exercises were common (89%) but only reported helpful by 56%. Use of biofeedback was recalled in 1/3 of subjects but reported helpful in only 14% of them. Anti-reflux, allergy, anticholinergics, inhalers and steroids were each used in >50%, but rarely reported effective. PVCM was reportedly a significant stressor when initially diagnosed but despite 2/3 of participants still reporting ongoing PVCM symptoms, the perceived stress significantly decreased over time (Z = 3.26, P = 0.001).

CONCLUSIONS

This first PVCM PRO study endorses that diagnosis is often delayed and prescribed treatments often viewed as ineffective. While biofeedback and breathing exercises may be critical for short-term control of PVCM episodes, lifestyle changes and stress reduction are likely necessary for long-term management. Increased awareness and improvements in management are needed for this condition.

Pulmonary manifestations of gastroesophageal reflux disease

INTRODUCTION

Gastroesophageal reflux disease (GERD) is a widespread condition with a significant impact on the quality of life and healthcare resources. In addition to its gastrointestinal problems, GERD has been linked to a variety of respiratory diseases either as a direct cause, or as a risk factor to the inability to control or worsening of the disease.

AREAS COVERED

We performed a literature search in the PubMed database for articles addressing GERD and pulmonary diseases. This review will discuss several different pulmonary diseases affected by GERD ranging from upper airway including chronic cough, vocal cord dysfunction, lower airway diseases including COPD, asthma, and bronchiolitis obliterans syndrome to parenchymal diseases such as interstitial lung diseases. The review will discuss several different pulmonary manifestations of GERD and their contribution to patient mortality and morbidity. It will also review the mechanisms leading to these diseases, diagnostic workup, and the role of the available treatment options.

EXPERT OPINION

GERD is often overlooked as a cause of respiratory symptoms and illnesses. The literature is sparse on the relation between GERD and respiratory diseases such as interstitial lung diseases and bronchiolitis obliterans including its role in pathogenesis, mechanisms of lung injury, and whether treatment of GERD is effective in managing such illnesses.

Chronic cough in Vocal Cord Dysfunction: Description of a clinical entity

BACKGROUND AND AIM

Vocal Cord Dysfunction (VCD) and chronic cough (CC) are challenging conditions which lead to significant quality of life impairment. The underlying mechanisms are poorly understood, but laryngeal dysfunction may be common to both conditions. The aim of this study was to determine the characteristics of cough in VCD and whether patients with cough have coexisting VCD.

METHOD

Participants included 51 patients with VCD and a comparison group of 39 patients with chronic cough that was refractory to medical treatment. Participants underwent a comprehensive assessment including questionnaires, laryngoscopy, cough frequency monitoring and voice testing.

RESULTS

Patients with VCD had significant cough morbidity with an increased cough frequency of 17.3 coughs/hour and reduced cough quality of life with mean Leicester Cough Questionnaire Score of 12.8. Breathing pattern abnormalities were also common in VCD and there was a strong correlation between the number of breathing pattern abnormalities and cough frequency (r = -0.827, p = 0.002). Cough measures were not significantly different between patients with VCD and those with CC. Moderate-severe PVFM was present in 69% of patients with CC. Abnormal vocal fold closure during phonation was also present in patients with chronic cough and was similar between the VCD (n = 40, 78.4%) and cough (n = 25, 64.1%) groups, p = 0.240.

CONCLUSION

Cough is an important symptom in VCD. Patients presenting with chronic cough may have underlying VCD as a cause of their cough. Since cough and VCD symptoms co-occur clinicians need to consider cough when are treating VCD and VCD when treating chronic cough.

Prevalence and impact of comorbid laryngeal dysfunction in asthma: A systematic review and meta-analysis

BACKGROUND

Laryngeal or vocal cord dysfunction has long been regarded as a mimic of asthma; however, recent evidence indicates that it may be a significant comorbid condition in patients with asthma.

OBJECTIVE

We aimed to systematically estimate the prevalence of comorbid laryngeal dysfunction (LD) in adults with asthma and characterize its clinical impact on asthma.

METHODS

Electronic databases were searched for relevant studies published until June 2019. Studies were included if LD was objectively defined by direct visualization of laryngeal movement. Outcomes included the prevalence of LD and its association with clinical asthma indicators, such as severity, control, and quality of life. Random effects meta-analyses were performed to calculate the estimates.

RESULTS

A total of 21 studies involving 1637 patients were identified. Overall, the pooled prevalence of LD in adults with asthma was 25% (95% CI = 15%-37%; I² = 96%). Prevalence estimates differed according to the diagnostic test utilized, with the lowest overall prevalence (4% [95% CI = 0%-10%; I² = 90%]) seen when LD was diagnosed by resting laryngoscopy without external stimuli; however, it was much higher when diagnosed by laryngoscopy studies utilizing an external trigger, such as exercise (38% [95% CI = 24%-53%; I² = 90%]) or in studies using a computed tomography-based diagnostic protocol (36% [95% CI = 24%-49%; I² = 78%]). Only 7 studies reported the associations between LD and clinical asthma indicators; inconsistencies between studies limited meaningful conclusions.

CONCLUSION

LD may be a common comorbidity in asthma, affecting about 25% of adult patients. Further prospective studies are needed to better characterize its clinical impact and the benefits of detecting and managing LD in patients with asthma.

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.

Differences in laryngeal movements during exercise in healthy and dyspnoeic adolescents

OBJECTIVES

To compare glottic and supraglottic movements in healthy adolescents and adolescents experiencing dyspnoea during strenuous exercise.

METHODS

Using the continuous laryngoscopy exercise (CLE)-test laryngeal movements during exercise were analysed in healthy controls (n = 28) and compared to subjects with exercise induced bronchoconstriction (EIB) (n = 10), exercise induced laryngeal obstruction (EILO) (n = 10) and subjects experiencing exercise-induced dyspnoea without having any of these diagnoses (n = 31). Images from the video recordings were assessed regarding glottic angle, glottic area and supraglottic area using the software measuring tool EILOMEA.

RESULTS

No significant differences were detected between controls, the dyspnoea group without a diagnosis of EIB or EILO and the EIB group regarding glottis angle, glottis area or supraglottic area at maximum effort. All three parameters differed significantly in the EILO group compared to the other groups (p=<0.001). In the group with EILO all but one had supraglottic obstruction (corresponding to a CLE-test score ≥2). Movement of the laryngeal structures, corresponding to a CLE-test score of 1, at glottic and/or supraglottic level was seen in 26 of 35 (74%) of controls, 34 out of 41 (83%) of patients in the dyspnoea group, and in 25 of 38 (66%) of EIB-subjects.

CONCLUSION

Minor movements at both glottic and supraglottic level are equally common in healthy controls as among adolescents with exercise induced dyspnoea without EIB or EILO and adolescents with EIB. Adolescents with EILO had a statistically significant more pronounced supraglottic obstruction than the other groups.

Clinical Evaluation of Deployed Military Personnel With Chronic Respiratory Symptoms: Study of Active Duty Military for Pulmonary Disease Related to Environmental Deployment Exposures (STAMPEDE) III

BACKGROUND

Chronic respiratory symptoms are frequently reported after Southwest Asia deployment in support of combat operations. The full spectrum of clinical lung diseases related to these deployments is not well characterized.

METHODS

Military personnel with chronic symptoms, primarily exertional dyspnea, underwent a standardized cardiopulmonary evaluation at two tertiary medical centers. Pulmonary function testing consisted of spirometry, lung volume, diffusing capacity, impulse oscillometry, and bronchodilator testing. Further testing included methacholine challenge, exercise laryngoscopy, high-resolution CT scan, ECG, and transthoracic echocardiography.

RESULTS

A total of 380 participants with a mean age of 38.5 ± 8.4 years completed testing. Asthma was the most common diagnosis in 87 patients (22.9%) based on obstructive spirometry/impulse oscillometry and evidence of airway hyperreactivity, whereas another 57 patients (15.0%) had reactivity with normal spirometry. Airway disorders included 25 (6.6%) with laryngeal disorders and 16 (4.2%) with excessive dynamic airway collapse. Interstitial lung disease was identified in six patients (1.6%), whereas 11 patients (2.9%) had fixed obstructive lung disorders. Forty patients (10.5%) had isolated pulmonary function abnormalities and 16 (4.2%) had miscellaneous disorders. The remaining 122 patients (32.1%) with normal studies were classified as undiagnosed exertional dyspnea. Significant comorbidities identified included elevated BMI > 30 kg/m² (34.2%), smoking (36.4%), positive allergy testing (43.7%), sleep apnea (38.5%), and esophageal reflux (13.6%). Mental health disorders and posttraumatic stress disorder were likewise common.

CONCLUSIONS

Postdeployment pulmonary evaluation should focus on common diseases, such as asthma and airway hyperreactivity, and include testing for upper airway disorders. Diffuse lung diseases were rarely diagnosed, whereas numerous comorbidities were common.

Noradrenergic Mechanisms in Fentanyl-Mediated Rapid Death Explain Failure of Naloxone in the Opioid Crisis

In December 2018, the Centers for Disease Control declared fentanyl the deadliest drug in America. Opioid overdose is the single greatest cause of death in the United States adult population (ages 18-50), and fentanyl and its analogs [fentanyl/fentanyl analogs (F/FAs)] are currently involved in >50% of these deaths. Anesthesiologists in the United States were introduced to fentanyl in the early 1970s when it revolutionized surgical anesthesia by combining profound analgesia with hemodynamic stability. However, they quickly had to master its unique side effect. F/FAs can produce profound rigidity in the diaphragm, chest wall and upper airway within an extremely narrow dosing range. This clinical effect was called wooden chest syndrome (WCS) by anesthesiologists and is not commonly known outside of anesthesiology or to clinicians or researchers in addiction research/medicine. WCS is almost routinely fatal without expert airway management. This review provides relevant clinical human pharmacology and animal data demonstrating that the significant increase in the number of F/FA-induced deaths may involve α-adrenergic and cholinergic receptor-mediated mechanical failure of the respiratory and cardiovascular systems with rapid development of rigidity and airway closure. Although morphine and its prodrug, heroin, can cause mild rigidity in abdominal muscles at high doses, neither presents with the distinct and rapid respiratory failure seen with F/FA-induced WCS, separating F/FA overdose from the slower onset of respiratory depression caused by morphine-derived alkaloids. This distinction has significant consequences for the design and implementation of new pharmacologic strategies to effectively prevent F/FA-induced death. SIGNIFICANCE STATEMENT: Deaths from fentanyl and F/FAs are increasing in spite of availability and awareness of the opioid reversal drug naloxone. This article reviews literature suggesting that naloxone may be ineffective against centrally mediated noradrenergic and cholinergic effects of F/FAs, which clinically manifest as severe muscle rigidity and airway compromise (e.g., wooden chest syndrome) that is rapid and distinct from respiratory depression seen with morphine-derived alkaloids. A physiologic model is proposed and implications for new drug development and treatment are discussed.

Environmental Exposures and Asthma in Active Duty Service Members

PURPOSE OF REVIEW

Reports of respiratory symptoms, including asthma and hyper-reactive airway disease, have been more numerous in the media and medical literature since active duty service members (SM) began to support campaigns in South West Asia (SWA). Numerous environmental exposures have been reported and this review assesses the available evidence surrounding exposures, confounding conditions, and attempts to develop screening mechanisms.

RECENT FINDINGS

While particulate matter exposures and particularly exposure to burn pits have garnered much attention, a 2010 Armed Forces Health Surveillance Center report and 2011 Institute of Medicine publication did not identify a link between exposure to particulate matter with SM respiratory disease. The "Study of Active Duty Military for Pulmonary Disease related to Environmental Deployment Exposure," (STAMPEDE) and STAMPEDE II have not identified effective forms of routine screening and these and other sources point to the importance of other factors in SM respiratory disease. These include higher than anticipated rates of tobacco use in deployed settings, impacts of obesity, recurrence of childhood asthma, and of confounding conditions such as Paradoxical Vocal Fold Motion. As with the general population, a complex set of clinical inputs and environmental exposures surround asthma and similar respiratory processes in SM. Concrete relationships and mechanisms for assessment continue to be assessed and refined, but clear associations and pathways have remained elusive.

Vocal Cord Dysfunction: The Spectrum Across the Ages

Vocal cord dysfunction (VCD) is an upper airway disorder characterized by exaggerated and transient glottic constriction causing respiratory and laryngeal symptoms. Although the origin of VCD symptoms is in the upper airway, it is frequently misdiagnosed as asthma resulting in significant morbidity. VCD can coexist with asthma or mimic allergic conditions affecting the upper airway. VCD may be difficult to diagnose, because patients are intermittently symptomatic and VCD awareness in the medical community is underappreciated. Once VCD is diagnosed and treated, most patients report significant improvement in their symptoms as well as a decrease in asthma medication use.

Inducible laryngeal obstruction: Endoscopic quantitative analysis of glottic aperture

OBJECTIVES

Using a method developed for this study, the objective was to perform a quantitative analysis of glottic aperture during the respiratory cycle in subjects suspected of having inducible laryngeal obstruction (ILO) and to compare results to healthy individuals. Correlations between glottic aperture and spirometric parameters were assessed.

METHODS

Subjects with high clinical suspicion of ILO and atypical inspiratory findings in spirometry had the images of their laryngoscopy displayed alongside a respiratory flow chart and both were recorded simultaneously. This method allowed detailed analysis of the glottic aperture by measuring the angle of the anterior commissure during inspiration and expiration. Healthy volunteers who performed the same tests and agreed to provide data to this study were used as a control group.

RESULTS

All 15 subjects with ILO and 16 healthy participants were evaluated successfully using the proposed method. Measures of the anterior commissure angle in the ILO versus control group were significantly different in all observed parameters and just three ILO subjects had an anterior commissure closure greater than 50% during the respiratory cycle. Inspired volume (FIF₅₀ ) and mid-vital capacity ratio (FEF₅₀ /FIF₅₀ ) had a significant correlation with glottic aperture parameters when considering the evaluation of the subjects all together.

CONCLUSION

The proposed method provided precise and quantitative analysis of glottic aperture during the respiratory cycle thus indicating that the usage of equipment that allows for such assessment should be encouraged. Also, the threshold of vocal cords closure accepted as indicative of ILO should be reconsidered, especially during the intercritical period of the disease.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:E349-E356, 2020.

Diagnosis of severe asthma

Patients with asthma that is uncontrolled despite high intensity medication can present in both primary and specialist care. An increasing number of novel (and expensive) treatments are available for patients who fail conventional asthma therapy, but these may not be appropriate for all such patients. It is essential that a rigorous evaluation process be undertaken for these patients to identify those with biologically severe asthma who will require novel therapies, and those who may improve with control of contributory factors. In this article, we describe three key steps in the diagnostic evaluation process for severe asthma. The first step is confirmation of asthma diagnosis with objective evidence of variable airflow obstruction. The second involves management of contributory factors such as non-adherence, poor inhaler technique, ongoing asthma triggers, and comorbidities. The third step involves phenotyping and endotyping of patients with severe asthma. We provide a practical approach to implementing these measures in both primary and secondary care.

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.

Upper airway wheezing: Inducible laryngeal obstruction vs. excessive dynamic airway collapse

There are multiple causes of dyspnea upon exertion in young, healthy patients to primarily include asthma and exercise-induced bronchospasm. Excessive dynamic airway collapse (EDAC) describes focal collapse of the trachea or main bronchi with maintained structural integrity of the cartilaginous rings. It is commonly associated with pulmonary disorders like bronchiectasis, chronic obstructive pulmonary disease and asthma. It is believed to result secondary to airway obstruction in these conditions. While uncommon in young, healthy adults, it has recently been found as a cause of dyspnea in this population. Inducible laryngeal obstruction (ILO) is an umbrella term that describes an induced, intermittent upper airway impediment. While ILO is found in 10% of young patients with exertional dyspnea, it is primarily inspiratory in nature due to paradoxical closure of the glottis or supraglottis. This report highlights the presentation of a United States Army soldier who after a deployment was given a diagnosis of asthma, later found to have ILO and was subsequently diagnosed with concurrent EDAC. We follow up with a literature review and discussion of symptomatology, diagnosis, exercise bronchoscopy, and treatment modalities for both EDAC and ILO.