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.

The Clinical Utility of Continuous Laryngoscopy During Exercise: A Report of Two Cases

Exertional dyspnea is a common and disabling symptom in otherwise healthy children and adolescents, as well as in children with baseline airway abnormalities. It impairs the quality of life and may be associated with fatigue and underperformance in sports. Exertional dyspnea can be caused by a wide variety of structural and psychogenic causes. Exercise-induced laryngeal obstruction (EILO) is a relatively prevalent entity in young people that usually presents with exertional stridor, coughing, and dyspnea caused by transient closure of the larynx. In more complex cases where conventional tests such as pulmonary function tests (PFTs), chest imaging, ECG, and echocardiography are unrevealing, continuous laryngoscopy during exercise (CLE) tests may provide diagnostic utility. In addition to the baseline abnormalities visualized by conventional laryngoscopy, CLE can assess dynamic laryngeal responses during exercise. This article describes the clinical characteristics of two pediatric patients with various degrees of laryngeal dysfunction at baseline and the utility of CLE testing in tailoring management strategies.

The impact of identifying laryngeal obstruction syndromes on reducing treatment of pediatric asthma: A systematic review

Inducible laryngeal obstruction (ILO) in children is underrecognized. This systematic review characterizes the scientific evidence on the impact of pediatric ILO diagnosis and treatment on asthma medication use. This review, registered with PROSPERO (CRD42020209168), utilized database searches in MEDLINE, EMBASE, CINAHL, and Web of Science from inception to October 2020. Both experimental and observational studies on ILO and asthma outcomes in patients ≤18 years were included. Population characteristics (sample size, sex, age, and comorbidities) and study outcomes (medication usage and respiratory symptoms) were extracted. The risk of bias was assessed with the National Toxicology Program's Office of Health Assessment and Risk of Bias Rating Tool. Data are presented narratively due to study heterogeneity. Of 1091 studies, 1076 titles and abstracts were screened after duplicate removal. Screening 31 full texts yielded eight pre-post studies. Patients were an average of 14.1 years old, 15% male, and >90% used asthma medication; 40% reported allergies, 30% gastroesophageal reflux, and 20% anxiety or depression. Most patients received at least one intervention, with 75% showing symptomatic improvement and >75% decreasing or stopping asthma medications. Studies were small with a high risk of selection, confounding, and detection bias. Asthma management was not a primary outcome in any of the studies. Overall, ILO patients were often diagnosed with or treated for asthma before ILO diagnosis. Evidence from individual studies suggests that comorbidities including ILO, gastroesophageal reflux, allergies, and anxiety should be considered in pediatric patients with asthma not responsive to medical therapy. Further research is required to determine the proportion of impacted asthma patients.

Self-reported exercise-induced dyspnea and airways obstruction assessed by oscillometry and spirometry in adolescents

BACKGROUND

Self-reported exercise-induced dyspnea (EID) is common among adolescents. Possible underlying pathologies are exercise-induced bronchoconstriction (EIB) and laryngeal obstruction (EILO). The forced oscillation technique (FOT) may evaluate exercise-induced changes in airway caliber.

AIM

To investigate in adolescents the relationship between EID, EIB (post-exercise fall in forced expiratory volume in 1s (FEV₁ )≥10%), EILO, and post-exercise challenge changes in FOT parameters.

METHODS

One hundred and forty-three subjects (97 with EID) of 13-15 years old underwent a standardized exercise challenge with FOT measurement and spirometry repeatedly performed between 2 and 30 min post-exercise. EILO was studied in a subset of 123 adolescents. Subjects showing greater changes than the healthy subgroup in the modulus of the inspiratory impedance were considered FOT responders.

RESULTS

EID-nonEIB subjects presented similar post-exercise changes in all FOT parameters to nonEID-nonEIB adolescents. Changes in all FOT parameters correlated with FEV₁ fall. 45 of 97 EID subjects responded neither by FEV₁ nor FOT to exercise. 19 and 18 subjects responded only by FEV₁ (onlyFEV₁ responders) or FOT (onlyFOTresponders), respectively. Only a lower baseline forced vital capacity (FVC)%predicted and a higher FEV₁ /FVC distinguished the onlyFEV₁ responders from onlyFOTresponders. FOT parameters did not present specific post-exercise patterns in EILO subjects.

CONCLUSION

FOT can be used to identify post-exercise changes in lower airway function. However, EID has a modest relation with both FEV₁ and FOT responses, highlighting the need for objective testing. More research is needed to understand whether onlyFEV₁ responders and onlyFOTresponders represent different endotypes.

Self-Reported Health in Adolescents With Exercise-Induced Laryngeal Obstruction; A Cross-Sectional Study

Background: Exercise-induced laryngeal obstruction (EILO) is common in young people with exertional breathing difficulties. Psychological characteristics have been proposed as underlying contributors; however, the evidence for this is limited. Objectives: Describe self-reported health, self-efficacy, and anxiety symptoms in adolescents with EILO, and address possible associations with EILO subtypes and severity. Methods: Cross-sectional study of 71/180 (39%) adolescents tested for EILO at Haukeland University Hospital during 2014-2016, age range 14-18 years. Validated questionnaires were used to assess general self-rated health, subjective health complaints (Health Behavior in School-aged Children-Symptom Check List; HBSC-SCL), general self-efficacy (GSE), and anxiety symptoms (SCARED). The outcomes were compared with normative data from comparable unselected populations. Results: The HBSC-SCL items for somatic complaints revealed weekly or more often occurrence of headache in 42%, abdominal pain in 30%, backache in 31%, and dizziness in 32%. For psychological complaints, corresponding figures were 26% for feeling low, 43% for irritability or bad mood, 33% for feeling nervous, and 38% for sleep problems. Mean (range) GSE score was 3.13 (2.2-4.0), and reports suggesting anxiety symptoms were rare. The outcomes were in line with normative data from comparable unselected populations. Self-rated health, and scores obtained for HBSC-SCL, GSE, and SCARED were similarly distributed across EILO subtypes and severity. Conclusion: Self-reported health, self-efficacy, and level of anxiety symptoms in adolescents with laryngoscopically confirmed EILO were similar to data obtained in comparable unselected populations, irrespective of EILO subtype and severity. The findings challenge the notion that pediatric EILO is causally related to psychological problems.

The interest of rehabilitation of respiratory disorders in athletes: Myth or reality?

BACKGROUND

Healthy trained athletes generally have an "overbuilt" respiratory system in order to face the huge ventilation and gas-exchange demand imposed by strenuous exercise. Athletes frequently complain of respiratory symptoms regardless of whether they have a diagnosed respiratory disease, therefore evoking a kind of respiratory limitation during exercise. Some respiratory pathologies athletes present are closely linked to exercise and include asthma, exercise-induced bronchoconstriction (EIB) or exercise-induced laryngeal obstruction. Management of asthma and EIB are mainly based on pharmacological treatments. However, many athletes still complain of respiratory symptoms despite optimal pharmacological treatments, which highlights the need for non-pharmacological approaches including breathing retraining, inspiratory muscle training and/or laryngeal exercise performed under the guidance of a physiotherapist in this specific population.

OBJECTIVES

With this literature overview, we aimed to report evidence supporting the interest of rehabilitation for athletes with respiratory disorders and discuss whether inspiratory muscle training programs can improve performance in healthy athletes.

METHODS

We searched MEDLINE and Cochrane databases for trials, reviews and meta-analyses assessing respiratory rehabilitation and muscle training programs in athletes by using the MesH terms "athletes", "asthma", "dyspnea", "rehabilitation" and "education" published from January 2010 to March 2020. The selection of articles was based on the author's expertise to elaborate this review of the literature.

RESULTS

Major findings suggest that breathing retraining may help asthmatic athletes better control their respiratory symptoms and that inspiratory muscle training may improve respiratory symptoms of exercise-induced laryngeal obstruction in athletes. Improvement of performance by respiratory muscle training still remains controversial.

CONCLUSIONS

Respiratory rehabilitation could be of interest in the specific population of athletes but should be further evaluated to improve the level of evidence of such strategies.

Exercise-induced laryngeal obstruction (EILO) in children and young adults: From referral to diagnosis

OBJECTIVE

To identify different presentations, referral patterns, comorbidities, and laryngoscopy findings in children and young adults with exercise-induced laryngeal obstruction (EILO).

METHODS

We performed a retrospective chart review of 112 patients, age <26 years, with EILO between 2013 and 2016.

RESULTS

Of the 112 patients who met criteria, 91 were female and 21 were male. Patients were most frequently referred by pulmonologists (60.7%). The majority of patients (93%) participated in organized sports, most of them at a competitive level. The mean age at symptom onset was 13.8 ± 3.3 years, and the mean age of diagnosis was 15.4 ± 3.0 years. Sixty-seven (59.8%) patients presented with a prior diagnosis of asthma, the majority of whom had failed asthma treatment. The most common symptoms reported were dyspnea (93.8%), wheezing/stridor (78.6%), and throat tightness (48.2%). Ninety-one (81.3%) patients had spirometry performed, with 46 (51.1%) showing inspiratory loop flattening. On flexible laryngoscopy, 87 (78.4%) of 111 patients had paradoxical vocal fold motion. Supraglottic involvement was observed to obstruct the airway in 26 (23.9%) patients, with patterns of obstruction similar to those observed in children with laryngomalacia.

CONCLUSION

Most patients participated in competitive sports, were female, and presented with exertional dyspnea. Most patients were diagnosed with exercise-induced asthma but treated unsuccessfully. Almost one-quarter of our patients showed supraglottic collapse obstructing the airway. Exercise-induced laryngeal obstruction is a more descriptive term than paradoxical vocal fold motion or vocal cord dysfunction, which only describe vocal fold involvement. The time to diagnosis of EILO was shorter than previously reported, suggesting that awareness of this condition is increasing.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:E400-E406, 2020.

Feasibility and tolerability of measuring translaryngeal pressure during exercise

Objectives/Hypothesis

To determine if simultaneous tracheal and supraglottic pressure measurement performed during a continuous laryngoscopy exercise (CLE) test is possible, tolerable, and feasible, and if so, whether measurements can be used to determined airflow resistance over the larynx, thus providing an objective outcome measure for the CLE test, the gold standard for diagnosing exercise‐induced laryngeal obstruction.

Study Design

Explorative descriptive clinical study.

Methods

A CLE test was performed with the addition of two pressure sensors (Mikro‐Cath 825‐0101; Millar, Houston, TX) placed at the epiglottic tip and at the fifth tracheal ring. To place sensors, laryngeal anesthesia and a channel scope were required. Tolerability and feasibility was determined by a Likert score and subjective indication from subjects and operators. Adjustments to the technique were made to increase tolerability. The pressure data were continuously collected and analyzed for artifacts, drifts, frequency response, and used with flow data to calculate translaryngeal resistance.

Results

All subjects (n = 7) completed all procedures. Two main areas of concern were identified regarding tolerability: application of topical anesthesia to the larynx and nasal discomfort due to the added diameter of the laryngoscope. Protocol adjustments improved both. Pressure data were obtained from all procedures in all subjects, were consistent, and followed physiological trends.

Conclusions

Continuous measurement of the translaryngeal pressure gradient during a CLE test is possible, feasible, and tolerable. A CLE test with direct measurement of the translaryngeal pressure gradient might become a valuable tool in the objective assessment of respiratory function, and normal values should be established in health and disease.

Level of Evidence

NA Laryngoscope, 129:2748–2753, 2019

Therapeutic laryngoscopy during exercise: A novel non-surgical therapy for refractory EILO

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) may affect as many as 6% of the adolescent population, with some patients experiencing symptoms refractory to conservative interventions.

OBJECTIVES

This report describes therapeutic laryngoscopy during exercise, a novel, non-surgical intervention that harnesses real-time laryngoscopy video as biofeedback to control laryngeal aperture during high-intensity exercise. Additionally, we quantitate patient-reported perceptions of procedure safety, tolerability, learning value, and effectiveness.

METHODS

Clinical EILO patients with symptoms refractory to conventional respiratory retraining and other therapies were referred for the procedure which features laryngoscopy video as biofeedback during serial physician-guided 1-min exercise sprints. We quantify perceptions of procedure safety, tolerability, learning value, and effectiveness through questionnaires offered to all patients as well as observers of the procedure.

RESULTS

Forty-one patients and 37 parent observers were approached for feedback; 88% of patients and 95% of observers consented to participation. Patients and observers reported perceptions of safety and tolerability (81% and 86%, respectively), learning value (78% and 91%, respectively), and effectiveness (58% and 80%, respectively) with patient age predicting some responses. Seventy-five percent of patients noted that "Since the procedure, my breathing during exercise has improved," and 85% of this group noted that therapeutic laryngoscopy during exercise was "the most important therapy leading to my breathing improvement." The procedure also provided insight into the psychological experience of patients, a domain not clinically apparent prior to the procedure.

CONCLUSIONS

Our data support further study of therapeutic laryngoscopy during exercise as a possible intervention for patients with refractory EILO. Pediatr Pulmonol. 2017;52:813-819. © 2016 Wiley Periodicals, Inc.

Severe asthma in children

Most children with asthma have their disease easily controlled if low-dose inhaled corticosteroids (ICSs) are regularly and correctly administered. If a child presents with asthma which is apparently resistant to therapy with high-dose ICS and other controllers, then they have problematic severe asthma. However, in light of the UK National Review of Asthma Deaths, definitions of severe asthma based solely on the levels of prescribed treatment are too narrow. A detailed assessment of all such children should be performed. First, the diagnosis of asthma should be confirmed, then co-morbidities assessed. Next, a nurse-led assessment further characterizes the problem, conventionally categorizing the child as either having difficult asthma or severe therapy-resistant asthma. Here, we reassess in particular the interactions between, and management of, these two categories, highlighting that this dichotomous classification may need reconsideration. We use bronchoscopy and an intramuscular steroid injection to determine if the child has steroid-resistant asthma, using a novel, multidomain approach because the adult definition does not apply to around half the children we see. Finally, we highlight some mechanistic data which have emerged from this protocol such as the absence of T-helper 2 (TH2) cytokines even in eosinophilic severe asthma and the potential role of the innate epithelial cytokine IL-33, novel data on lineage negative innate lymphoid cells, which we can measure in induced sputum, and demonstrating that intraepithelial neutrophils are associated with better, not worse asthma outcomes. Severe paediatric asthma is very different from severe asthma in adults, and approaches must not be uncritically extrapolated from adult disease to children.

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

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