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The reader will come to appreciate: • Many adults who were born extremely preterm in the 1980s and 1990s, and who did not develop bronchopulmonary dysplasia, have lung function in the low normal range. • Extremely preterm born infants with a history of bronchopulmonary dysplasia may be at increased risk of a chronic obstructive pulmonary disease in middle age and older years based on the trajectory of their lung function. • Despite improved neonatal care and the advent of surfactant therapy, the rate of bronchopulmonary dysplasia has not decreased. Extreme preterm (EP) birth, denoting delivery before the onset of the third trimester, interrupts intrauterine development and causes significant early-life pulmonary trauma, thereby posing a lifelong risk to respiratory health. We conducted a systematic review and meta -analysis to investigate adult lung function following EP birth (gestational age <28 weeks); comparing forced expiratory volume in first second (FEV 1), forced vital capacity (FVC), and FEV 1 /FVC to reference values. Subgroup differences were explored based on timing of birth relative to surfactant use (1991) and bronchopulmonary dysplasia (BPD) status. Systematic searches were performed in Medline, EMBASE, Web of Science and Cochrane Central. Quality assessments were carried out using a modified Newcastle-Ottawa Scale for cohort studies. Sixteen studies encompassing 1036 EP-born adults were included, with 14 studies (n = 787) reporting data as %predicted, and 11 (n = 879) as z-score (not mutually exclusive). Overall mean [95 % confidence interval (CI)] %FEV 1 was 85.30 (82.51; 88.09), %FVC was 94.33 (91.74; 96.91), and FEV 1 /FVC was 79.54 (77.71 to 81.38), all three with high heterogeneity. Overall mean (95 %CI) zFEV 1 was −1.05 (-1.21; −0.90) and zFVC was. −0.45 (-0.59; −0.31), both with moderate heterogeneity. Subgroup analyses revealed no difference in FEV 1 before versus after widespread use of surfactant, but more impairments after neonatal BPD. This meta -analysis revealed significant airflow limitation in EP-born adults, mostly explained by those with neonatal BPD. FEV 1 was more reduced than FVC, and FEV 1 /FVC was at the lower limit of normal. Although at a group level, most adult EP-born individuals do not meet COPD criteria, these findings are concerning. [ABSTRACT FROM AUTHOR]

Many survivors of preterm birth will have abnormal lung development, reduced peak lung function and, potentially, an increased rate of physiological lung function decline, each of which places them at increased risk of chronic obstructive pulmonary disease across the lifespan. Current rates of preterm birth indicate that by the year 2040, around 50 years since the introduction of surfactant therapy, more than 700 million individuals will have been born prematurely—a number that will continue to increase by about 15 million annually. In this Personal View, we describe current understanding of the impact of preterm birth on lung function through the life course, with the aim of putting this emerging health crisis on the radar for the respiratory community. We detail the potential underlying mechanisms of prematurity-associated lung disease and review current approaches to prevention and management. Furthermore, we propose a novel way of considering lung disease after preterm birth, using a multidimensional model to determine individual phenotypes of lung disease—a first step towards optimising management approaches for prematurity-associated lung disease. [ABSTRACT FROM AUTHOR]

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. We sought to establish consensus-based diagnostic criteria and methods for VCD/ILO. 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. 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. This Delphi study reached consensus on multiple aspects of VCD/ILO diagnosis and can inform clinical practice and facilitate research. [ABSTRACT FROM AUTHOR]

The authors comment on a study published within the issue which analyzed flow and pressure graphs generated by mechanical insufflation-exsufflation (MI-E) treatment to detect unwanted upper-airway responses and how this could aid in choosing the right treatment parameters for amyotrophic lateral sclerosis (ALS). Topics covered include the strengths and limitations of the study, and the important contribution of the study to the field of laryngeal involvement in respiratory care.

When the ability to cough is impaired, secretion clearance may be assisted and augmented with mechanical insufflation-exsufflation (MI-E). In some individuals, the efficacy of MI-E may be hampered by counterproductive upper airway reactions, where the airways close in response to positive pressures. To fully utilize the therapeutic potential inherent in the MI-E technology, we need a better understanding of the pathophysiology behind these untoward reactions. There is increasing interest in monitoring and measuring upper airway responses to MI-E and how such information can be used to optimize MI-E settings. The purpose of this narrative review is to increase the theoretical understanding of the larynx as a respiratory organ, summarize the current literature in the area, and provide insight into how this knowledge can affect current clinical practice [ABSTRACT FROM AUTHOR]

Maximal expiratory airflow peaks early in the third decade of life, then gradually declines with age. The pattern of airflow through adulthood for individuals born very preterm (at <32 weeks' gestation) or with very low birthweight (<1501 g) is unknown. We aimed to compare maximal expiratory airflow in these individuals during late adolescence and early adulthood with that of control individuals born with normal birthweight (>2499 g) or at term. We did a meta-analysis of individual participant data from cohort studies, mostly from the pre-surfactant era. Studies were identified through the Adults born Preterm International Collaboration and by searching PubMed and Embase (search date May 25, 2016). Studies were eligible if they reported on expiratory flow rates beyond 16 years of age in individuals born very preterm or with very low birthweight, as well as controls born at term or with normal birthweight. Studies with highly selected cohorts (eg, only participants with bronchopulmonary dysplasia) or in which few participants were born very preterm or with very low birthweight were excluded. De-identified individual participant data from each cohort were provided by the holders of the original data to a central site, where all the data were pooled into one data file. Any data inconsistencies were resolved by discussion with the individual sites concerned. Individual participant data on expiratory flow variables (FEV 1 , forced vital capacity [FVC], FEV 1 /FVC ratio, and forced expiratory flow at 25–75% of FVC [FEF 25–75% ]) were converted to Z scores and analysed with use of generalised linear mixed models in a one-step approach. Of the 381 studies identified, 11 studies, comprising a total of 935 participants born very preterm or with very low birthweight and 722 controls, were eligible and included in the analysis. Mean age at testing was 21 years (SD 3·4; range 16–33). Mean Z scores were close to zero (as expected) in the control group, but were reduced in the very preterm or very low birthweight group for FEV 1 (−0·06 [SD 1·03] vs −0·81 [1·33], mean difference −0·78 [95% CI −0·96 to −0·61], p<0·0001), FVC (−0·15 [0·98] vs −0·38 [1·18], −0·25 [–0·40 to −0·10], p=0·0012), FEV 1 /FVC ratio (0·14 [1·10] vs −0·64 [1·35], −0·74 [–0·85 to −0·64], p<0·0001), and FEF 25–75% (−0·04 [1·10] vs −0·95 [1·47], −0·88 [–1·12 to −0·65], p<0·0001). Similar patterns were observed when we compared the proportions of individuals with values below the fifth percentile. Individuals born very preterm or with very low birthweight are at risk of not reaching their full airway growth potential in adolescence and early adulthood, suggesting an increased risk of chronic obstructive pulmonary disease in later adulthood. National Health and Medical Research Council (Australia), University of Bergen, Western Norway Regional Authority, National Institute for Health Research (UK), Stichting Astmabestrijding, St Olav's Hospital's Research Fund, Academy of Finland, European Commission, National Institute of Child Health and Human Development (USA), Victorian Government's Operational Infrastructure Support Program. [ABSTRACT FROM AUTHOR]

The article discusses a study that formed an in vitro model to explore the role played by the upper airways while using the mechanical insufflation-exsufflation cough-enhancement technique. Highlights include the role of the larynx in controlling air-flow resistance during exercise, the use of several resistance-compliance models to imitate conditions in the respiratory system, and a new geometry generated by the structural changes caused by the air-flow.

BACKGROUND: Respiratory complications represent the major cause of death in amyotrophic lateral sclerosis (ALS). Noninvasive respiratory support is the mainstay therapy, but treatment becomes challenging as the disease progresses, possibly due to a malfunctioning larynx, which is the entrance to the airways. We studied laryngeal response patterns to mechanically assisted cough (mechanical insufflation-exsufflation) as ALS progresses. METHODS: This prospective longitudinal study of 13 consecutively included subjects with ALS were followed up during 2011-2016 with repeated tests of lung function, neurological status, and laryngeal responses to mechanical insufflation-exsufflation using video-recorded flexible transnasal fiberoptic laryngoscopy. RESULTS: Follow-up time was median 17 (range 6-59) months. In total, 751 laryngoscopy recordings from 67 individual examinations (median 4 per subject, range 2-11 per subject) were analyzed. Adverse laryngeal events that developed with disease progression during insufflation included adduction of true vocal folds in 8 of 9 spinal-onset subjects and adduction of aryepiglottic folds in all subjects, initially at the highest positive pressure and prior to onset of other bulbar symptoms in spinal-onset subjects. As cough became less expulsive with disease progression, laryngeal adduction occurred at lower insufflation pressures. Retroflex movement of the epiglottis was observed in 7 of 13 subjects regardless of insufflation pressures and independent of bulbar involvements. Backward movement of the tongue base occurred regardless of insufflation pressures in all but 1 subject. During exsufflation, constriction of the hypopharynx was observed in all subjects regardless of the presence of bulbar symptoms, after the adverse events that occurred during insufflation. CONCLUSIONS: Applying high insufflation pressures during mechanically assisted cough in ALS can become counterproductive as the disease progresses as well as prior to the onset of bulbar symptoms. The application of positive inspiratory pressures should be tailored to the individual patient, and laryngoscopy during ongoing treatment appears to be a feasible tool. [ABSTRACT FROM AUTHOR]

Being born preterm often adversely affects later lung function. Airway obstruction and bronchial hyperresponsiveness (BHR) are common findings. Respiratory symptoms in asthma and in lung disease after preterm birth might appear similar, but clinical experience and studies indicate that symptoms secondary to preterm birth reflect a separate disease entity. BHR is a defining feature of asthma, but can also be found in other lung disorders and in subjects without respiratory symptoms. We review different methods to assess BHR, and findings reported from studies that have investigated BHR after preterm birth. The area appeared understudied with relatively few and heterogeneous articles identified, and lack of a pervasive understanding. BHR seemed related to low gestational age at delivery and a neonatal history of bronchopulmonary dysplasia. No studies reported associations between BHR after preterm birth and the markers of eosinophilic inflammatory airway responses typically found in asthma. This should be borne in mind when treating preterm born individuals with BHR and airway symptoms. [ABSTRACT FROM AUTHOR]

Obstruction of the central airways is an important cause of exercise-induced inspiratory symptoms (EIIS) in young and otherwise healthy individuals. This is a large, heterogeneous and vastly understudied group of patients. The symptoms are too often confused with those of asthma. Laryngoscopy performed as symptoms evolve during increasing exercise is pivotal, since the larynx plays an important role in symptomatology for the majority. Abnormalities vary between patients, and laryngoscopic findings are important for correct treatment and handling. The simplistic view that all EIIS is due to vocal cord dysfunction [VCD] still hampers science and patient management. Causal mechanisms are poorly understood. Most treatment options are based on weak evidence, but most patients seem to benefit from individualised information and guidance. The place of surgery has not been settled, but supraglottoplasty may cure well-defined severe cases. A systematic clinical approach, more and better research and randomised controlled treatment trials are of utmost importance in this field of respiratory medicine. [ABSTRACT FROM AUTHOR]

When the ability to cough is impaired, secretion clearance may be assisted and augmented by Mechanical Insufflation-Exsufflation (MI-E) treatment. In patients with Amyotrophic Lateral Sclerosis, the efficacy of MI-E may be hampered by counterproductive upper airway responses. Careful adjustment of MI-E settings can be beneficial. During the disease progression, a 41-year-old woman with bulbar Amyotrophic Lateral Sclerosis experienced that treatment with MI-E was exhausting and inefficient. Despite adjustments of settings, all treatment led to retching. A change of MI-E device led to more effective treatment. A bench test revealed variations in flow and pressure waveforms in the two devices. When MI-E treatment fails, differences in equipment delivery need to be considered in addition to the adjustment of MI-E settings. • Effective airway clearance and subjective tolerance must be targeted to maintain compliance with MI-E therapy in ALS. • Examination of MI-E waveforms may provide clinically relevant information. • Skillful adjustment of MI-E settings and knowledge of performance between devices may be important with challenging patients. [ABSTRACT FROM AUTHOR]