Lung function trajectories in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease characterised by decline in lung function. We evaluated trajectories of forced vital capacity (FVC) and diffusing capacity (DLco) in a cohort of patients with IPF. METHODS: Patients with IPF that was diagnosed or confirmed at the enrolling centre in the previous 6 months were enrolled into the IPF-PRO Registry between June 2014 and October 2018. Patients were followed prospectively, with lung function data collected as part of routine clinical care. Mean trajectories of FVC and DLco % predicted in all patients and in subgroups by characteristics assessed at enrolment were estimated using a joint model that accounted for factors such as disease severity and visit patterns. RESULTS: Of 1002 patients in the registry, 941 had ≥ 1 FVC and/or DLco measurement after enrolment. The median (Q1, Q3) follow-up period was 35.1 (18.9, 47.2) months. Overall, mean estimated declines in FVC and DLco % predicted were 2.8% and 2.9% per year, respectively. There was no evidence that the mean trajectories of FVC or DLco had a non-linear relationship with time at the population level. Patients who were male, white, had a family history of ILD, were using oxygen, or had prior/current use of antifibrotic therapy at enrolment had greater rates of decline in FVC % predicted. Patients who were male or white had greater rates of decline in DLco % predicted. CONCLUSIONS: Data from the IPF-PRO Registry suggest a constant rate of decline in lung function over a prolonged period, supporting the inexorably progressive nature of IPF. A graphical abstract summarising the data in this manuscript is available at: https://www.usscicomms.com/respiratory/IPF-PRORegistry_LungFunctionTrajectories . TRIAL REGISTRATION: NCT01915511.

Dose-dependent impact of human milk feeding on tidal breathing flow-volume loop parameters across the first 2 years of life in extremely low-birth-weight infants: a cohort study.

The purpose of this study is to test the hypothesis that higher consumption of human milk (HM) in preterm infants with birth weight (BW) <1000 g is associated with improved lung function in a dose-dependent manner over the first 2 years of corrected age (CA). This retrospective study at an academic medical center included infants with BW <1000g. They had lung function assessment by the tidal breathing flow-volume loop (TBFVL) follow-up visits at 0-3-, 3-6-, 6-12-, 12-18-, and 18-24-month CA. One hundred eighty infants were included in the study with a mean (SD) gestational age 26.5 (1.90) weeks and BW 772.4 (147.0) g, 50% were female, and 60% developed BPD. 62.8% of infants received HM during the NICU stay. According to a general linear model (including GA, being small for GA (SGA), sex, human milk percentage, sepsis, and BPD), on average, each week of GA resulted in a higher tPTEF/tE of 1.24 (p = 0.039) and being SGA in a lower tPTEF/tE of 5.75 (p = 0.013) at 0-3-month CA. A higher percentage of human milk out of the total enteral intake was associated with better tPTEF/tE z-scores at 0-3 months (p = 0.004) and 18-24 months of CA (p = 0.041). BPD diagnosis was associated with a relevantly worse tPTEF/tE z-score at 6-12 months of CA (p = 0.003). CONCLUSION: Preterm infants with higher consumption of HM had significantly less airway obstruction across the first 2 years, suggesting that human milk may contribute in a dose-dependent manner to improve lung function in early childhood in former preterm infants born ELBW. WHAT IS KNOWN: • Human milk feeding reduces the risk of prematurity-related morbidities, including necrotizing enterocolitis, sepsis, lower respiratory tract infections, and BPD. Both exclusive and partial human milk feeding appear to be associated with a lower risk of BPD in preterm infants. WHAT IS NEW: • This cohort study of 180 preterm infants with birth weight < 1000 g found that exposure to human milk during hospitalization improves airway obstruction markers tPTEF/tE z-score over the first 2 years of corrected age in a dose-dependent manner.

Re-opening the pediatric pulmonary function laboratory during the ongoing COVID-19 pandemic.

The COVID-19 pandemic continues with new waves of intensification. This review provides an update based on international recommendations concerning the conduct of pulmonary function testing in a manner to limit risk to both patient and tester.

The role of impulse oscillometry in the management of asthma when forced expiratory maneuvers are contraindicated: case series and literature review.

Objectives: The impulse oscillometry system (IOS) provides an alternative method of lung function testing for patients in whom forced expiratory manoeuvres are contraindicated, such as those with inherited vascular connective tissue disorders. Here we examine the role of IOS in the diagnosis and monitoring of asthma in such patients through a clinical case series and literature review.Methods: The clinical case series comprised of data from 12 patients with inherited connective tissue disorders representing 32 clinical encounters. Of these, 11 encounters were for asthma diagnosis and 21 were for asthma monitoring. Symptoms, exhaled nitric oxide (FeNO) and IOS were assessed at each encounter.Results: In the clinical case series, 5 of 6 patients with likely asthma (as determined by physician review and exhaled nitric oxide testing) had abnormal IOS parameters compared with 0 of 5 of those with unlikely asthma. In the monitoring group, 11 encounters resulted in treatment escalation (demonstrating suboptimal control), and 8 resulted in no change to treatment (good control). Six of 11 of those with suboptimal control had abnormalities in ≥3 IOS parameters, with R5 and R5-20 most frequently affected. Only 1 of 8 of those with good control had abnormalities in ≥3 IOS parameters.Conclusions: IOS can be used as an alternative to conventional lung function testing to support the diagnosis and monitoring of asthma when forced expiratory manoeuvres are contraindicated. Larger studies are required to establish severity and treatment escalation thresholds and provide clearer comparisons with spirometry values.

Phrenic nerve conduction study to diagnose unilateral diaphragmatic paralysis.

BACKGROUND: Unilateral diaphragmatic paralysis (UDP) has major clinical and etiological implications and, therefore, is important to diagnose. Lung function tests and invasive transdiaphragmatic pressure (Pdi) measurements are widely used to this end but, contrary to phrenic nerve conduction study (NCS), they require volitional maneuvers and/or may be poorly tolerated by patients. The purpose of this study was to compare the diagnostic accuracy of Pdi and phrenic NCS for UDP. METHODS: We retrospectively reviewed 28 patients with suspected UDP. The diagnosis established during a multidisciplinary meeting was the reference standard. RESULTS: Phrenic NCS correlated well with Pdi (r = 0.82, P < .005), and the two tests showed good agreement (κ = 0.82, P < .005). Phrenic NCS and Pdi measurements both had 95% sensitivity, 87.5% specificity, 95% positive predictive, and 87.5% negative predictive values. CONCLUSIONS: Both tests were highly sensitive and specific. Phrenic NCS measurement is a simple, reproducible, noninvasive method whose results correlate well with Pdi and provide insight into the UDP mechanism. In the most difficult cases, combining lung function tests, respiratory muscle assessments, and phrenic NCS can help to establish the diagnosis.

Whole-Body Lung Function Test-Derived Outcome Predictors in Allogenic Stem Cell Transplantation.

Despite clinical advances, late onset pulmonary complications in adult recipients of allogenic stem cell transplantation are a major cause of morbidity and mortality. Reported incidence and risk factors in the literature vary broadly and are partly contradictory. Identification of pretransplant factors associated with major complications would be helpful to define individual treatment strategies and early initiation of preventive measures. To evaluate incidence and risk factors of late onset noninfectious pulmonary complications, with special regard to small airways disease (SAD) and bronchiolitis obliterans syndrome (BOS), indicating graft-versus-host disease, following myeloablative versus nonmyeloablative allogenic stem cell transplantation. We reviewed the clinical records and assessed the course of lung function and pulmonary complications in adults who underwent allogenic stem cell transplantation for hematological malignancies between 1999 and 2015 using nonmyeloablative (n = 179) or myeloablative (n = 130) conditioning at the Division of Hematology of the Medical University of Graz. All patients underwent body plethysmography pulmonary function test (PFT), diffusion capacity for carbon monoxide, and arterial blood gas analysis before and repeatedly after transplant. SAD was defined as maximal expiratory flow at 50% and 25% of forced vital capacity <70% predicted. Ventilatory disorders and gas transfer abnormalities were common before and after allogenic stem cell transplantation, independent of conditioning regimen. SAD was common in the nonmyeloablative (34%) and myeloablative (29%) groups. The 100-day post-transplant mortality was significantly associated with reduced pretransplant total lung capacity <80%. Mortality 100 days post-transplant was significantly associated with pretransplant SAD and a pretransplant smoking history. In this subset, a smoking history was independently associated with increased mortality, with a 5-year mortality of 45% compared with 26% in never-smokers. Pretransplant SAD was not predictive for the later development of BOS. Smoking history, pretransplant restrictive PFT, and pre-existing SAD are important risk factors for death following allogenic stem cell transplantation. However, pretransplant SAD is not a predictor of long-term complications, including BOS.

Lung Function Changes are More Common in Marfan Patients Who Need Major Thoracic Surgery.

INTRODUCTION: Marfan syndrome is a genetic disorder affecting the connective tissue. Changes in lung tissue might influence respiratory function; however, a detailed respiratory functional assessment according to the need for major thoracic surgery is missing. METHODS: Comprehensive pulmonary examinations were performed in 55 Marfan patients including respiratory symptoms, lung function (LF) testing using European Coal and Steel Community (ECSC) reference values, TLCO and quality of life measurements. Groups included patients who did not need surgery (Mf, n = 32) and those who underwent major thoracic surgery (Mfop, n = 23). RESULTS: Respiratory symptoms affected 20% of patients. Scoliosis was significantly more frequent in the Mfop group. LF demonstrated in all Marfan patients a tendency towards airway obstruction (FEV1/FVC = 0.77 ± 0.10), more prominent in Mfop patients (0.74 ± 0.08 vs. Mf: 0.80 ± 0.11; p = 0.03). Correction of LF values using a standing height modification by arm span (Hcorrected) revealed additional changes in FVC and FEV1. TLCO and quality of life did not differ between groups. CONCLUSIONS: Marfan syndrome is associated with airway obstruction, especially in patients who have undergone major thoracic surgery, indicative of more severe connective tissue malfunction. The use of arm span for height correction is suitable to evaluate LF changes in this special patient group including patients with significant scoliosis.

Long-term sequelae after lung abscess in children - Two tertiary centers' experience.

AIM: The aim of the study was to describe the epidemiology and clinical characteristic of children hospitalized with pneumonia complicated by lung abscess, as well as to evaluate the long-term sequelae of the disease. METHODS: A retrospective review of medical records of all patients treated for pulmonary abscess in two tertiary centers was undertaken. Pulmonary function tests and lung ultrasound were performed at a follow-up. RESULTS: During the study period, 5151 children with pneumonia were admitted, and 49 (0.95%) cases were complicated with lung abscess. In 38 (77.5%) patients, lung abscess was treated solely with antibiotics, and in nine cases (16.3%) surgically. In 21 (51.21%) children complete radiological regression was documented. The mean time for radiological abnormalities regression was 84.14 ± 51.57 days, regardless of the treatment mode. Fifteen patients were followed up at 61.6 ± 28.3 months after discharge. Lung ultrasound revealed minor residual abnormalities: pleural thickening, subpleural consolidations and line B artefacts in 11 (73.3%) children. Pulmonary function tests results were abnormal in eight (53.3%) patients, the most frequent abnormality being hyperinflation. We did not find a restrictive disorder in any of the children. There were no deaths in our study. CONCLUSIONS: Lung abscess is a rare but severe complication of pneumonia in children. Most children recover uneventfully with no significant long-term pulmonary sequelae.

Relationship between pulmonary hyperinflation and dyspnoea severity during acute exacerbations of cystic fibrosis.

BACKGROUND AND OBJECTIVE: Acute exacerbations of cystic fibrosis (CF) occur frequently throughout the course of the disease. Dyspnoea is the most common and distressing symptom experienced by patients during these episodes. We tested the hypothesis that pulmonary hyperinflation is an important determinant of dyspnoea severity during acute exacerbations. METHODS: We studied patients during an acute exacerbation of CF. Lung volumes, spirometry and dyspnoea scores were measured at Day 0, Day 7, at the end of treatment (EOT) and 14 days following the EOT. RESULTS: At the start of treatment, mean residual volume (RV)/total lung capacity (TLC) was 54.9%, which decreased significantly with treatment, as did vital capacity (VC), inspiratory capacity (IC) and dyspnoea scores. IC was the only independent predictor of dyspnoea severity. CONCLUSION: Our study demonstrates significant improvements in hyperinflation, spirometry and dyspnoea scores with treatment of acute exacerbations of CF. Hyperinflation, rather than airflow limitation, may contribute towards the increased dyspnoea during exacerbations.

An approach to interpreting restrictive spirometric pattern results in occupational settings.

OBJECTIVES: The aim of this review is to provide an updated overview of definition, epidemiology, diagnostic algorithm and occupational exposures related to abnormal restrictive spirometrical pattern (RSP) in order to improve the correct interpretation of spirometry test results by occupational healthcare providers. METHODS: A review of the scientific English literature of the last 25 years was carried out with MEDLINE and related keywords [(restricti* AND spirometr*) AND occupational]. The first step analysis covered 40 studies and the second step the reference list. Results are presented in four major aims and subquestions. RESULTS: A spirometrical pattern of reduced VC (Vital Capacity), together with a normal FEV1 (Forced Expiratory Volume in 1 Second)/VC ratio, is suggestive, though not diagnostic of restrictive ventilatory defect (RVD). The prevalence of RSP is high in some studies, comparable to obstructive pattern, and could be associated to chronic medical conditions (diabetes, congestive heart failure, obesity, hypertension) as well as to increased risk of mortality and lung cancer. In order to predict true restrictive defect [TLC-(Total Lung Capacity)

Asthma, respiratory symptoms and lung function in children living near a petrochemical site.

Residential proximity to environmental hazards has been related to adverse health outcomes. Respiratory health and allergies in children living near petrochemical sites have not been extensively studied. We evaluated the association between residential proximity to the petrochemical site of Tarragona (Catalonia, Spain) and the prevalence of asthma, respiratory symptoms and lung function in children. Children aged 6-7 (n=2672) and adolescents aged 13-14 (n=2524) residing near two large petrochemical sites and those living in a city with medium vehicular traffic were cross-sectionally compared with children from an area with low vehicular traffic and without industry. The prevalence of symptoms was measured using the International Study of Asthma and Allergies in Childhood written and video questionnaires. Lung function measurements were done in a subsample of 959 adolescents in the four areas. Multivariable analyses were done to estimate the effects of the residential area on symptoms and lung function adjusted for potential confounders. Crude prevalence of symptoms was similar across the studied areas. After adjustment, children and adolescents living near a petrochemical site had a statistically significant higher prevalence of respiratory hospitalizations in the previous year (Prevalence Ratio (PR)=1.49; 95%CI, 1.06-2.09) and of nocturnal cough (PR=1.29; 95%CI 1.05-1.57), respectively. Reduced lung function values among adolescents residing near the petrochemical areas were not observed. Although a higher prevalence of asthma in children and adolescents living near the petrochemical sites could not be demonstrated, as described in other studies, respiratory hospitalizations and nocturnal cough could be related to short-term exposures to pollutants. Other clinical and sub-clinical respiratory health effects in the petrochemical industry areas should be investigated.

Evaluation of Stress Scores of Healthy Adult Cats during Barometric Whole-Body Plethysmography and Its Correlation with Measurement Parameters.

Barometric whole-body plethysmography (BWBP) is considered to be a particularly gentle method of assessing lung function in cats. However, there have been no studies to date investigating the stress experienced by cats during measurements. The prospective study included 48 healthy adult cats. Each cat was measured in the plethysmographic chamber for a total of 30 min and stress levels were determined every 10 min using a stress ethogram. At the beginning of measurements, 75% of cats were assessed as tense. Over the three time periods, a significant (p < 0.001) reduction in the total stress score was observed. In addition, all measurement parameters correlated significantly with the stress score, with the exception of enhanced pause and tidal volume. It can therefore be assumed that cats will initially experience stress during examination in the plethysmographic chamber, but stress will decrease significantly over time. As the stress level correlates with many measurement parameters, this should be taken into account when interpreting the results.

[Respiratory oscillometry: Theoretical foundations and clinical applications]. / L'oscillométrie respiratoire : théorie et applications cliniques.

Oscillometry measures the mechanical properties of the respiratory system. As they are carried out during spontaneous breathing, oscillometry measurements do not require forced breathing maneuvers or the patient's active cooperation. The technique is complementary to conventional pulmonary function testing methods for the investigation of respiratory function, diagnosis and monitoring of respiratory diseases, and assessment of response to treatment. The present review aims to describe the theoretical foundations and practical methodology of oscillometry. It describes the gaps in scientific evidence regarding its clinical utility, and provides examples of current research and clinical applications.

Oscillatory mechanics in very preterm infants on continuous positive airway pressure support: Reference values.

OBJECTIVE: To create reference values for respiratory system resistance (Rrs) and reactance (Xrs) measured by the forced oscillation technique (FOT) in nonintubated very preterm infants. DESIGN: Retrospective analysis of data collected as part of prospective observational studies in two centers. SETTING: Tertiary neonatal intensive care units. PATIENTS: Non-intubated infants below 32 weeks' gestation age who did not develop bronchopulmonary dysplasia. INTERVENTIONS: We applied FOT using a mechanical ventilator (Fabian HFOi; Vyaire) that superimposed small-amplitude oscillations (10 Hz) on a continuous positive airway pressure of 3 and 5 cmH2 O. Measurements were performed during regular tidal breathing using a face mask. MAIN OUTCOME MEASURES: We analyzed 198 measurements performed between 7 postnatal days and 40 weeks postmenstrual age (PMA) in 85 infants, with a median (Q1, Q3) gestational age of 30.43 (29.14, 31.18) weeks. Logarithmic transformations were applied to Rrs and Xrs, and the relationship between transformed impedance values and demographic factors was examined by backwards stepwise linear regression. RESULTS: In univariable analysis, transformed Xrs was significantly associated with PMA, postnatal age, weight, and length, while Rrs was not. The best multivariable regression model estimating transformed Xrs (cmH2 O*s/L) at continuous positive airway pressure (CPAP) = 5 cmH2 O was: Ln(50 - Xrs) = 4.536 - 0.009 x PMA - 0.014 x weight z-score. SEE = 0.053, R2 = 0.36. The mean (SD) Rrs at CPAP = 5 cmH2 O was 33.63 (5.28) cmH2 O*s/L. CONCLUSION: We have established reference values for Rrs and Xrs at 10 Hz in nonintubated preterm neonates on continuous positive airway pressure support.

A Longitudinal Analysis of Equine Asthma Presentation and Response to Treatment Using Lung Function Testing and BAL Cytology Analysis in Combination with Owner Perception.

(1) Background: Equine asthma (EA) is a pervasive and important cause of poor performance and respiratory morbidity in horses. Diagnosis of EA includes an owner complaint, clinical scoring, lung function testing, and cytological analysis of bronchoalveolar lavage (BAL) cytology. There is a paucity of information about the longitudinal course of the disease using these outcome assessments; thus, this study sought to describe and quantify, in horses with more than one visit to a specialty pulmonary clinic in New England, the type and range of clinical presentations with an eventual diagnosis of EA. It also aimed to develop and compare the outcomes of scoring systems for owner complaints and veterinary assessments, document and assess the diagnostic methods used, and evaluate the response of the horses to treatment and time. (2) Methods: This study was a retrospective, cross-sectional, STROBE-compliant observational analysis of equine patients who visited the Tufts Cummings Hospital for Large Animals (HLA) for evaluation of equine asthma (EA) from 1999-2023. The horses were categorized as having mild-moderate (mEA) or severe EA (sEA) using the ACVIM consensus statement guidelines. After excluding those with inadequate documentation or only one visit (n = 936), a total of 76 horses were included in the study. Of the 197 visits, 138 (70.0%) resulted in a diagnosis of mEA and 45 (22.8%) resulted in a diagnosis of sEA. Demographic information, owner complaints, clinical examination and scoring, lung function testing, BAL cytology, and recommendations for environmental remediation and pharmacologic treatment were recorded for all the visits. The data were analyzed for agreement between owner complaints (complaint score, CS) and clinical examination findings (examination score, ES), changes in CS and ES, lung function testing, and BAL cytology over time, with 197 visits recorded. (3) Results: A comparison between the CS and ES showed that the owners were more likely than veterinarians to detect cough, and a decrease in cough was the most common owner observation after treatment. The response to the histamine challenge, used to detect airway hyperreactivity, was significantly improved with treatment or time in the horses with mEA, whereas baseline lung function did not significantly change in mEA or sEA. (4) Conclusions: Owners can be astute observers of clinical signs, especially cough, in EA. Tests of airway hyperreactivity are more successful in detecting changes in mEA than are baseline lung function testing and assessment of BAL cytology.

Computed cardiopulmonography and the idealized lung clearance index, iLCI2.5, in early-stage cystic fibrosis.

This study explored the use of computed cardiopulmonography (CCP) to assess lung function in early-stage cystic fibrosis (CF). CCP has two components. The first is a particularly accurate technique for measuring gas exchange. The second is a computational cardiopulmonary model where patient-specific parameters can be estimated from the measurements of gas exchange. Twenty-five participants (14 healthy controls, 11 early-stage CF) were studied with CCP. They were also studied with a standard clinical protocol to measure the lung clearance index (LCI2.5). Ventilation inhomogeneity, as quantified through CCP parameter σlnCl, was significantly greater (P < 0.005) in CF than in controls, and anatomical deadspace relative to predicted functional residual capacity (DS/FRCpred) was significantly more variable (P < 0.002). Participant-specific parameters were used with the CCP model to calculate idealized values for LCI2.5 (iLCI2.5) where extrapulmonary influences on the LCI2.5, such as breathing pattern, had all been standardized. Both LCI2.5 and iLCI2.5 distinguished clearly between CF and control participants. LCI2.5 values were mostly higher than iLCI2.5 values in a manner dependent on the participant's respiratory rate (r = 0.46, P < 0.05). The within-participant reproducibility for iLCI2.5 appeared better than for LCI2.5, but this did not reach statistical significance (F ratio = 2.2, P = 0.056). Both a sensitivity analysis on iLCI2.5 and a regression analysis on LCI2.5 revealed that these depended primarily on an interactive term between CCP parameters of the form σlnCL*(DS/FRC). In conclusion, the LCI2.5 (or iLCI2.5) probably reflects an amalgam of different underlying lung changes in early-stage CF that would require a multiparameter approach, such as potentially CCP, to resolve.NEW & NOTEWORTHY Computed cardiopulmonography is a new technique comprising a highly accurate sensor for measuring respiratory gas exchange coupled with a cardiopulmonary model that is used to identify a set of patient-specific characteristics of the lung. Here, we show that this technique can improve on a standard clinical approach for lung function testing in cystic fibrosis. Most particularly, an approach incorporating multiple model parameters can potentially separate different aspects of pathological change in this disease.

Migration is not the perfect answer: How the cross-talk error correction for multiple breath nitrogen washout (MBWN2 ) parameters differs on directly collected vs. legacy data.

Recently, a cross-talk error with commercial multiple breath nitrogen washout (MBWN2 ) software was discovered, which produced an absolute over-reading of N2 of approximately 1%, i.e., 2% N2 read as 3%. This caused an extended tail to the washout, and over-estimated lung clearance index (LCI2.5 ) values. Subsequently an updated and corrected software version has been released. Within the field there have been discussions on how to correct legacy data, whether to migrate or completely "rerun" raw data A-files from the old software into the new corrected software. To our knowledge, no research has been published assessing whether either method is equivalent to directly collecting data in the new corrected software. We prospectively recruited 19 participants, 10 adult healthy controls and 9 people with cystic fibrosis (CF). MBWN2 was performed using the Exhalyzer® D first on the old 3.1.6 software and next, directly on corrected 3.3.1 software. Multiple breath washout (MBW) data directly collected in 3.3.1 was significantly different from both migrated and rerun data. A total of 7 of the 19 participants (37%; 4 CF) had a relative difference in LCI2.5 > 10% for both migrated and rerun data compared to 3.3.1 collected data. Our findings have implications for the Global Lung Initiative MBW project, which is accepting a combination of directly collected, A-file reruns and migrated data to establish normative values. Further, caution must be used in clinical practice when comparing corrected legacy data versus 3.3.1 collected data for clinical interpretation. We recommend that a new baseline is collected directly on 3.3.1. before clinical interpretation and decisions are determined when comparing consecutive MBW tests.

Improving Access and Guideline Adherence in Pulmonary Care in Patients With Duchenne Muscular Dystrophy.

BACKGROUND: Duchenne muscular dystrophy (DMD) is a devastating, progressive neuromuscular disease that results in cardiopulmonary failure and death. In 2018, the DMD Care Considerations guidelines were updated to improve the multidisciplinary approach to care and promote early respiratory management. We sought to evaluate the impact of a multidisciplinary clinic on access to pulmonary care and adherence to respiratory care guidelines. METHODS: Utilizing retrospective data, we assessed for pulmonary care between 2016-2019 and congruence with guidelines from March 2018-February 2019. Using a standardized visit protocol, subjects were monitored for adherence to pulmonary function testing (PFT) and polysomnography (PSG) recommendations. RESULTS: Of the 84 subjects with DMD, only 51.2% had prior pulmonary involvement, and approximately one-third were seen in the year prior to clinic onset. Only 23% of subjects with a pulmonary referral completed this visit. After clinic initiation, the average age of a subject's first pulmonary contact decreased from 11.8 y to 7.9 y (P < .001), and 45% of the 77 unique clinic subjects had no previous pulmonary encounter. Adherence to PFT guidelines increased in both ambulatory (8.7% to 86.1%) and non-ambulatory subjects (25.9% to 90.1%). Approximately 79% of subjects seen in clinic either completed or had an order for PSG in the last 12 months. CONCLUSIONS: Development of a multispecialty clinic expanded access to pulmonary care and evaluation in subjects with DMD. Continued care in this clinic will allow a better understanding of barriers to access and the opportunity to monitor long-term pulmonary health.

Myocardial strain in newborn infants with tracheomalacia due to vascular rings, a pilot study.

BACKGROUND: Vascular rings (VR) may cause severe tracheomalacia and upper airway obstruction (UAO). Increased pulmonary artery pressure and cardiac dysfunction have been described in patients with chronic UAO, but has not been investigated in infants with obstruction associated with VR. The aim of this study is to evaluate myocardial strain in infants with UAO due to VR. METHOD: Demographic characteristics, respiratory symptoms, percentage of tracheal obstruction measured and classified using Computer Tomography, and lung function testing (LFT) were collected. Left (LV) and right ventricle (RV) systolic functions were measured using speckle tracking echocardiography longitudinal strain analysis (LS). Pulmonary artery pressure was evaluated using maximal tricuspid regurgitation jet velocity (TR) and LV end-systolic eccentricity index (EI). RESULTS: Fifteen cases were included in the study, six had mild tracheal obstruction (<50%), nine moderate-severe obstruction (≥50%). LV LS and RV LS were significantly reduced in cases with moderate to severe airway obstruction cases compared to those with mild airway obstruction (LV LS -15.9 versus -19.9%; RV LS -15.7 versus -20.5%, p = .04 and p = .02, respectively). Respiratory symptoms were more pronounced in moderate-severe cases. No significant differences in TR, EI, and LFT were observed. CONCLUSIONS: In cases of VR with severe tracheomalacia RV and LV myocardial strain is reduced, suggesting secondary cardiac dysfunction.

Heterogenous Disease Course and Long-Term Outcome of Children's Interstitial Lung Disease Related to Filamin A Gene Variants.

Rationale: Variable disease course and outcomes have been reported in children's interstitial lung disease associated with FLNA (Filamin A gene) variants. Objectives: To further delineate long-term respiratory outcomes and identify potential contributing factors to severe disease course. Methods: We retrospectively collected longitudinal data from three centers on nine cases (one male) with FLNA variants and early respiratory disease onset (within the first 24 mo of life). Clinical, radiographic, and histopathologic data were analyzed, focusing on cardiorespiratory disease course. Results: All required early respiratory support (three invasive ventilation, three noninvasive ventilation, three supplemental oxygen), and all experienced frequent severe infective respiratory exacerbations. Three died in infancy from refractory respiratory failure and pulmonary hypertension (PH). The six surviving individuals were 3, 10, 11, 15, 18, and 33 years old at time of reporting. The extent of functional respiratory impairment decreased with age; at last follow-up, there were no individuals on home invasive ventilation, one on nocturnal noninvasive ventilation, four on oxygen, and one on no respiratory support. Spirometry consistently demonstrated moderate to severe obstructive defects (forced expiratory volume in 1 s/forced vital capacity [FVC] z-score, -3.76 to -1.77; percent predicted FVC, 31.5% to 92.1%). Seven required PH treatment in early childhood (7/9), and three of the survivors (3/6) still receive treatment. Radiologic and histopathologic findings were consistent among cases. Conclusions: Early mortality was common, but many survivors stabilized even after severe symptoms in infancy. All survivors had persistent obstructive defects on spirometry, and half have persistent or recurrent PH. These typical findings are suggestive of this rare diagnosis and should prompt consideration of genetic testing.