Dynamic airway computed tomography and flexible bronchoscopy for diagnosis of tracheomalacia in children: A comparison study.

INTRODUCTION: Tracheomalacia (TM) is an important cause of respiratory morbidity. Dynamic flexible bronchoscopy is considered the gold standard for diagnosis. Dynamic airway computed tomography (DACT) is a low radiation, noninvasive diagnostic tool utilizing images obtained continuously over several respiratory cycles. We aimed to assess the accuracy of DACT in TM diagnosis. METHODS: Retrospective analysis of all patients who underwent both DACT and flexible bronchoscopy within 6 months. Airway anterior-posterior (AP) diameter was measured on multiplanar reconstructions CT in both the inspiratory and expiratory phases. Using still images from the bronchoscopy videos, the AP diameter of the trachea was measured at points of maximal and minimal diameter during tidal breathing. Degree of TM on both DACT and flexible bronchoscopy were graded using a scaling system of 50%-74%, 75%-89%, and 90%-100% as described by the European Respiratory Society. RESULTS: Twenty-four patients met inclusion criteria with an average time of 19.5 days between CT and bronchoscopy. The specificity and sensitivity of DACT for the overall diagnosis of TM was 100% and 68%, respectively, with a positive predictive value of 100% and a negative predictive value of 62%. There was a strong positive correlation between DACT and flexible bronchoscopy in the measurement of tracheal AP diameter changes (ρ = 0.773, R2 0.597, p = 0.00001). Mean effective radiation dose for DACT was 0.1 mSv. CONCLUSION: Ultralow dose DACT has excellent specificity and positive predictive value for both detection of TM and categorizing severity of tracheal collapse but is not sufficiently sensitive to rule it out.

Diagnostic yield of endobronchial ultrasound and virtual CT navigational bronchoscopy for biopsy of pulmonary nodules, mediastinal lymph nodes, and thoracic tumors in children.

OBJECTIVE: Endobronchial ultrasound-guided transbronchial biopsy and needle aspiration (EBUS-TBB/EBUS-TBNA) are first line investigative modalities for lung and mediastinal pathology in adults. We aimed to characterize and assess the diagnostic yield of EBUS and virtual CT navigation guided biopsies in children. STUDY DESIGN: This single center, retrospective cohort study included patients who underwent radial or linear EBUS procedures (+/- CT navigation) for biopsy of mediastinal lymph nodes, tumors, and pulmonary nodules. Demographic, procedural, and outcome were collected. RESULTS: Sixty procedures were performed in 56 patients aged 2-22 years of age between January 2015 and May 2023. The most common indications for biopsy were pulmonary nodules (45%) and hilar/mediastinal lymphadenopathy (33%). For cases in which a final diagnosis was ascertained by any means, the diagnostic yield for linear EBUS (mediastinal pathology) was 76% and the diagnostic yield from radial EBUS (pulmonary nodules and lung masses) was 85%. The most common diagnoses were infection (45%), malignancy (17%), and sarcoidosis (11%). Among patients in whom infection was the final diagnosis, a total of 31 pathogens were identified. Eighteen were identified on bronchoalveolar lavage and an additional 14 pathogens identified on EBUS-TBB, representing an increase of 77% (p < .005). The sensitivity, specificity, negative and positive predictive values for malignancy detection were 73%, 100%, 94%, and 100%, respectively. CONCLUSION: EBUS-TBB/TBNA is a safe and effective way to diagnose lung and mediastinal pathology in children. Pediatric interventional pulmonology is a growing field offering minimally-invasive diagnostic opportunities for children in whom more invasive procedures were previously the only option.

Eosinophilic plastic bronchitis: Case series and review of the literature.

Plastic bronchitis is a term used to describe group of life-threatening disorders characterized by the presence of large obstructing casts in the airways. Eosinophilic plastic bronchitis is a subtype of plastic bronchitis that occurs mainly in children and has not been well-described in the literature. Patients may have a history of asthma or atopy, but many do not. They often present with cough and wheezing, and frequently have complete collapse of one lung seen on imaging. The severity of presentation varies depending on the location of the casts, ranging from mild symptoms to severe airway obstruction and death. Bronchoscopy is often required to both diagnose and treat this condition. A variety of medical therapies have been used, although no formal studies have evaluated their efficacy. Symptoms may resolve after initial cast removal, but in some patients, cast formation recurs. Here, we report a case series of nine patients with eosinophilic plastic bronchitis and review the existing literature of this condition.

A multicenter study analyzing the impact of pre-existing comorbidities on laryngotracheal reconstruction (LTR) outcomes.

INTRODUCTION: Comorbidities such as chronic lung disease and gastroesophageal reflux (GERD), prematurity, and numerous other conditions may impact the success of LTR. Single-center studies are limited in terms of patient numbers and may be underpowered. OBJECTIVES: To analyze the impact of specific comorbidities on the operation-specific and overall surgical success of LTR in a large multicenter cohort and validate a predictive model for surgical success. METHODS: A large retrospective multicenter 10-year review was undertaken to validate the data of a previous single-center study (Wertz et al. Laryngoscope 2020) which identified specific predictive comorbidities which impacted LTR outcomes. A Monte Carlo simulation based on the previous data set suggested that 300-400 cases would be needed to optimize the statistical power of a Bayesian model developed from the single-center data to predict surgical success. An IRB-approved data-sharing agreement was executed for 4 large U.S. CENTERS: A virtual REDCap® data entry form inquired about patient characteristics that best predicted surgical success in the single-center model. These included demographics, surgical approaches, cardiac, airway, genetic, endocrine, musculoskeletal, gastrointestinal, and pulmonary comorbidities; details of the surgical procedures, and results of esophagogastroduodenoscopy (EGD), esophageal pH/impedance and flexible bronchoscopy with bronchioalveolar lavage (BAL) were included. Surgical success defined as successful decannulation or resolution of airway symptoms was recorded as single surgery success and overall success following open surgical revision surgery. Multivariate Bayesian analysis, logistical regression, and Kaplan-Meier analysis were performed. RESULTS: 542 patients were identified, including 165 from the single-center study and an additional 377 patients from the multicenter group. The median age was 36 months at the time of the most recent surgery. 70.9% of the LTRs were double-staged procedures. The overall success rate was 86.4% and operation-specific success rate was 69.2%. The specific comorbidities and aerodigestive test results that impacted success based on univariate analysis included staging, bronchiectasis, pulmonary hypertension, GERD, ASD, PDA, grade of stenosis, advanced levels of stenosis, Trisomy 21, MRSA, prior open surgery at another hospital, and gross appearance on EGD. Bayesian model averaging with backward selection was used to validate and refine a predictive model for surgical success with favorable receiver operating curve characteristics - AUC values of 0.827 for single surgery success and 0.797 for overall success. DISCUSSION: With over 500 patients reviewed, this was the largest multicenter study of LTR to date, which elucidated the impact of comorbidities on success with LTR and was able to improve upon the predictive modeling based on single-center data. Patient factors are most critical in the outcome of LTR. Stage and levels of stenosis, as well as pulmonary and GI conditions most strongly impact the likelihood of success. Future prospective case-control studies will be performed to further optimize the current model for outcome prediction and patient management.

Rare airway tumor in a previously healthy adolescent successfully treated with endoscopic resection and oral propranolol.

Airway tumors are rare in children. Pyogenic granuloma (PG), also known as lobular capillary hemangioma, is a benign vascular tumor usually found on the skin or in the oral cavity. Rarely, these lesions occur in the airway and cause significant hemoptysis. Most reported airway PGs have occurred in the trachea of adults. Here, we present a case of an adolescent female who presented with hemoptysis and was found to have a PG in the right lower lobe. Per institutional guidelines, this case report was exempt from institutional review board approval.

Mixed-methods process evaluation of a respiratory-culture diagnostic stewardship intervention.

OBJECTIVE: To conduct a process evaluation of a respiratory culture diagnostic stewardship intervention. DESIGN: Mixed-methods study. SETTING: Tertiary-care pediatric intensive care unit (PICU). PARTICIPANTS: Critical care, infectious diseases, and pulmonary attending physicians and fellows; PICU nurse practitioners and hospitalist physicians; pediatric residents; and PICU nurses and respiratory therapists. METHODS: This mixed-methods study was conducted concurrently with a diagnostic stewardship intervention to reduce the inappropriate collection of respiratory cultures in mechanically ventilated children. We quantified baseline respiratory culture utilization and indications for ordering using quantitative methods. Semistructured interviews informed by these data and the Consolidated Framework for Implementation Research (CFIR) were then performed, recorded, transcribed, and coded to identify salient themes. Finally, themes identified in these interviews were used to create a cross-sectional survey. RESULTS: The number of cultures collected per day of service varied between attending physicians (range, 2.2-27 cultures per 100 days). In total, 14 interviews were performed, and 87 clinicians completed the survey (response rate, 47%) and 77 nurses or respiratory therapists completed the survey (response rate, 17%). Clinicians varied in their stated practices regarding culture ordering, and these differences both clustered by specialty and were associated with perceived utility of the respiratory culture. Furthermore, group "default" practices, fear, and hierarchy were drivers of culture orders. Barriers to standardization included fear of a missed diagnosis and tension between practice standardization and individual decision making. CONCLUSIONS: We identified significant variation in utilization and perceptions of respiratory cultures as well as several key barriers to implementation of this diagnostic test stewardship intervention.

Hemosiderin-Laden Macrophages in Bronchoalveolar Lavage Samples of Children with Bronchopulmonary Dysplasia.

OBJECTIVES: To evaluate the prevalence of hemosiderin-laden macrophages in children with bronchopulmonary dysplasia (BPD) and assess for an association between hemosiderin-laden macrophages and pulmonary arterial hypertension. STUDY DESIGN: Retrospective case-control study of infants and children with and without BPD who underwent bronchoscopy with bronchoalveolar lavage (BAL) the at Children's Hospital of Philadelphia between 2012 and 2021. RESULTS: BAL from 205 children with BPD and 106 controls without BPD matched for tracheostomy, infection, and age were reviewed for hemosiderin-laden macrophages. Seventy-one individuals (34.6%) with BPD had a BAL with 10% or more hemosiderin-laden macrophages compared with 3 (2.8%) controls (P < .0001; OR, 18.19; 95% CI, 5.57-59.41). Patients with pulmonary hypertension by echocardiogram (P = .04; OR, 3.69; 95% CI, 1.05-12.96) or an elevated mean pulmonary artery pressure during cardiac catheterization, rs (14) = 0.56, P = .04, were more likely to have elevated hemosiderin-laden macrophages on BAL samples less than 60 days from bronchoscopy. After adjusting for birth weight, gestational age, BPD grade, and age at the time of bronchoscopy using logistic regression, pulmonary hypertension was associated with a higher odds of hemosiderin-laden macrophages of 10% or more (P = .02; OR, 6.37; 95% CI, 1.28-31.87). No association was observed between hemosiderin-laden macrophages and sex, race, gestational age, birth weight, tracheostomy, or infectious studies. CONCLUSIONS: This retrospective study revealed increased hemosiderin-laden macrophages in BAL samples from patients with BPD and a significant association with pulmonary arterial hypertension. It is unclear whether elevated hemosiderin-laden macrophages within BPD contributes to the pathogenesis of lung and pulmonary vascular disease or is simply a biomarker of pulmonary arterial hypertension.

Comparison of tracheal aspirate and bronchoalveolar lavage samples in the microbiological diagnosis of lower respiratory tract infection in pediatric patients.

BACKGROUND: Bacterial cultures from tracheal aspirates (TA) and bronchoalveolar lavage (BAL) specimens can be used to assess patients with artificial airways for lower respiratory tract infections (LRTI). TA collection may be advantageous in situations of limited resources or critical illness. Literature comparing these diagnostic modalities in pediatric populations is scarce. METHODS: Single-center, retrospective analysis of 52 pediatric patients with an artificial airway undergoing evaluation for LRTI. All patients had a TA specimen collected for semiquantitative Gram stain and culture followed by BAL within 48 h. Microbiologic diagnosis of LRTI was defined as a BAL sample with >25% neutrophils and growth of >104 colony-forming units/ml of one or more bacterial species. The test characteristics of TA were compared with these BAL results as the reference standard. Concordance in microorganism identification was also assessed. RESULTS: Overall, 24 patients (47%) met criteria for LRTI using BAL as the diagnostic standard. TA samples positive for an isolated organism had poor sensitivity for acute LRTI when compared with BAL, regardless of semiquantitative white blood cell (WBC) count by Gram stain. Using a TA diagnostic threshold of organism growth and at least "moderate" WBC yielded a specificity of 93%. Positive predictive value was highest when an organism was identified by TA. Negative predictive value was >70% for TA samples with no WBC by semiquantitative analysis, with or without growth of an organism. Complete concordance of cultured species was 58% for all patients, with a higher rate seen among those with endotracheal tubes. CONCLUSIONS: The role of cultures obtained by TA remains limited for the diagnosis of acute LRTI as demonstrated by the poor correlation to BAL results within our cohort. Optimal strategies for diagnosing LRTI across patient populations and airway types remain elusive.

Consensus on Triple Endoscopy Data Elements Preparatory to Development of an Aerodigestive Registry.

OBJECTIVES/HYPOTHESIS: This study defines essential data elements to be recorded during an aerodigestive "triple endoscopy" to form the foundation of a standardized multicenter registry and to clearly define measurement of each consensus item. STUDY DESIGN: Modified Delphi process. METHODS: Modified Delphi consensus with six survey rounds. Twenty-four expert pediatric otolaryngology, pulmonology, and gastroenterology aerodigestive clinicians from eight large academic pediatric aerodigestive programs formed the Delphi panel. After achieving consensus through the Delphi process, outside validation was performed at 2019 national Aerodigestive Society conference. Consensus, near-consensus, or exclusion was obtained for each proposed data element. Concordance was then measured between expert panel conclusions and validation group conclusions. RESULTS: Overall response rate was 94.4%. 73/167 proposed items reached consensus in six domains (flexible bronchoscopy, bronchoalveolar lavage, microdirect laryngoscopy and bronchoscopy, esophagogastroduodenoscopy with biopsies, and esophageal impedance and pH probe). Measurement of all items was defined; classification/grading systems were selected for 11 items. Validation group endorsed importance of 82/167 data items; compared to expert consensus, overall, inclusion, and exclusion concordance rates were 94.5%, 98.7%, and 90.9%. CONCLUSION: Triple endoscopy is a central component of aerodigestive care. This study identifies and defines data elements to be recorded for all triple endoscopy procedures. The list is of usable length, and clear definitions were created for all items, with explicit classification/grading systems selected for 11 items. Face validity was confirmed with an independent multispecialty sample of aerodigestive providers. This consensus provides the foundation for a triple endoscopy registry but also is immediately applicable to standardize clinical documentation in aerodigestive care. LEVEL OF EVIDENCE: 5 Laryngoscope, 132:2251-2258, 2022.

Successful whole lung lavage in a child with pulmonary alveolar proteinosis secondary to hematologic malignancy.

Pulmonary alveolar proteinosis (PAP) describes the accumulation of surfactant in the alveolar space. Secondary PAP has been reported in a variety of diseases, and in rare cases has been associated with hematologic malignancy. Treatment for PAP is based on the underlying disease process, and may include whole lung lavage, inhaled or subcutaneous granulocyte-macrophage colony-stimulating factor, or statins. PAP secondary to hematologic malignancy has been reported to demonstrate poor response to whole lung lavage. We report a case of successful treatment of a pediatric patient with acute myeloid leukemia and secondary PAP using whole lung lavage.

Pilot study for comparative assessment of dual-energy computed tomography and single-photon emission computed tomography V/Q scanning for lung perfusion evaluation in infants.

OBJECTIVE: To evaluate clinical applications of dual-energy computed tomography (DECT) in pediatric-specific lung diseases and compare ventilation and perfusion findings with those from single-photon emission computed tomography (SPECT-CT) V/Q. METHODS: All patients at our institution who underwent exams using both techniques within a 3-month period were included in this study. Two readers independently described findings for DECT, and two other readers independently analyzed the SPECT-CT V/Q scan data. All findings were compared between readers and disagreements were reassessed and resolved by consensus. Inter-modality agreements are described throughout this study. RESULTS: Eight patients were included for evaluation. The median age for DECT scanning was 3.5 months (IQR = 2). Five of these patients were scanned for both DECT and SPECT-CT V/Q studies the same day, and three had a time gap of 7, 65, and 94 days between studies. The most common indications were chronic lung disease (5/8; 63%) and pulmonary hypertension (6/8; 75%). DECT and SPECT-CT V/Q identified perfusion abnormalities in concordant lobes in most patients (7/8; 88%). In one case, atelectasis limited DECT perfusion assessment. Three patients ultimately underwent lobectomy with corresponding perfusion abnormalities identified by all reviewers on both DECT and SPECT-CT V/Q in all resected lobes. CONCLUSION: DECT is a feasible technique that could be considered as an alternative for SPECT-CT V/Q for lung perfusion evaluation in infants.

Clinical predictors of laryngotracheoesophageal clefts and tracheoesophageal fistulae in children with dysphagia.

Laryngotracheoesophageal clefts (LTECs) and tracheoesophageal fistulae (TEF) are important structural causes of aspiration requiring bronchoscopy for diagnosis. Determining which children are at greatest risk for LTEC and TEF would enable clinicians to be more selective in performing bronchoscopy. METHODS: Medical records of children aged 0-18 years who underwent flexible and rigid bronchoscopy for evaluation of dysphagia with aspiration were collected and analyzed to identify predictors of LTEC and TEF. RESULTS: Seventy-two children age 2 months to 9 years were identified. LTEC was identified in 19 (26%) and TEF was identified in 1 (1.3%). One-third of the cohort was born preterm (median gestational age 34 weeks). The proportion of LTEC in those born preterm was lower than that of those born full-term (12% vs. 34%, p = .03). There was no statistically significant difference in LTEC prevalence based on age, midline defects, laryngomalacia, tracheomalacia, history of TEF repair, silent aspiration, or viscosity of barium aspirated during videofluoroscopic swallowing studies. Bronchoalveolar lavage fluid cytology, lipid-laden macrophage proportions, and culture results were similar among those with and without LTEC. CONCLUSION: Children with dysphagia and tracheal aspiration born full-term are three times more likely to have LTEC than those born preterm. Dysphagia in children with a history of preterm birth is more likely to be functional as opposed to structural, however, LTEC was identified in approximately 10% of these children and must be considered. These results support the role of bronchoscopy in children with dysphagia with tracheal aspiration.

Three-dimensional printed realistic pediatric static and dynamic airway models for bronchoscopy and foreign body removal training.

For mastering bronchoscope handling, positioning, and directing of the bronchoscope in response to the intraluminal view provided by the bronchoscope camera, sufficient training is necessary, especially in infants and toddlers who have smaller airways, faster respiratory rates, and higher airway collapsibility. With the use of three-dimensional printing, we aimed to develop a set of anatomically accurate and low-cost airway models for teaching and training of bronchoscopy technique and foreign body removal: a translucent airway box model, a static airway model, and a dynamic airway model consisting of a flexible tree model connected to a pump that allows simulation of airway collapsibility during breathing. Computed tomography (CT) patient data of three different ages (1, 5, and 18 years of age) was imported into Materialise Mimics, segmented, and printed using VisoClear and soft Tango+ material. The models were evaluated by three pediatric pulmonology attendings for anatomical accuracy and usefulness for teaching and training. The translucent airway box model was preferred for the initial presentation of bronchoscope handling and learning anatomy in three dimensions. The static and flexible tree models were used to train bronchoscope handling and foreign body removal. The dynamic model provided the most realistic representation of a pediatric airway throughout the respiratory cycle with increased patency during inspiration and relative collapse during exhalation. Objective verification of anatomical accuracy and physiology of breathing motion was obtained by comparing CT scans of the model with original images and by application of 4D dynamic CT airway imaging protocols, respectively.

Impact of Pre-operative Multidisciplinary Evaluation on Laryngotracheal Reconstruction Outcomes.

OBJECTIVE/HYPOTHESIS: Determine if diagnostic findings from pre-operative multidisciplinary evaluations are associated with single surgery or overall success rates in pediatric laryngotracheal reconstruction (LTR). STUDY DESIGN: Retrospective cohort. METHODS: Retrospective cohort study of patients undergoing LTR at a tertiary care children's hospital between January 01, 2008 and December 31, 2017. Success is defined as decannulation rate if tracheostomy present, and resolution of symptoms if tracheostomy not present. Cohorts compared were those who did and did not receive pulmonary and gastrointestinal preoperative testing. Multivariate, logistic regression, and Kaplan Meier analyses performed. RESULTS: About 165 children were included in the study. Median age was 3 years at the time of surgery; 73% of LTRs were double-stage procedures. Single surgery and overall success rates were 75% and 87%, respectively. After adjusting for severity of stenosis and surgical approach, performing esophagogastroduodenoscopy (EGD) and normal gross appearance on EGD were associated with increased single surgery (P = .01, .005) and overall success (P = .005, .0003). Performing pH probe and normal EGD biopsy results was associated with increased overall success (P = .03, .007). Asthma and musculoskeletal comorbidities, postoperative complications, and need for postoperative balloon dilation were associated with decreased success. No other comorbidities evaluated impacted success. CONCLUSIONS: Aerodigestive comorbidities are common in children undergoing LTR, and preoperative multidisciplinary workup often results in changes in management. After adjusting for grade and level of stenosis and staged approach, performing EGD and pH/impedance probe as well as normal gross and microscopic EGD findings was independently associated with increased LTR surgical success. LEVEL OF EVIDENCE: 4 (retrospective cohort study) Laryngoscope, 131:E2356-E2362, 2021.

Innovating and adapting in pediatric pulmonology and sleep medicine during the COVID-19 pandemic: ATS pediatric assembly web committee consensus statement for initial COVID-19 virtual response.

Coronavirus disease 2019 (COVID-19) has been an unprecedented and continuously evolving healthcare crisis. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) spread rapidly and initially little was known about the virus or the clinical course for infected children. In the United States of America, the medical response has been regionalized, based on variation in community transmission of the virus and localized outbreaks. Pediatric pulmonary and sleep divisions evolved in response to administrative and clinical challenges. As the workforce transitioned to working remotely, video conferencing technology and multicenter collaborative efforts were implemented to create clinical protocols. The COVID-19 pandemic challenges the framework of current medical practice but also highlights the dynamic and cooperative nature of pediatric pulmonology and sleep medicine. Our response to this pandemic has laid the groundwork for future challenges.

Clinical Factors Influencing Time to Decannulation in Children with Tracheostomy and Ventilator Dependence Secondary to Bronchopulmonary Dysplasia.

OBJECTIVE: To determine whether demographic or clinical factors affected the time to tracheostomy decannulation for patients with severe bronchopulmonary dysplasia (BPD). STUDY DESIGN: We retrospectively abstracted information from the electronic medical record for 93 patients with BPD or chronic lung disease of prematurity with tracheostomy and ventilator dependence cared for in our Pulmonary Clinic between January 1, 2006, and December 31, 2015. Univariable and multivariable models controlling for sex, race, ethnicity, and gestational age assessed the impact of cohort demographics, comorbid medical conditions, and physician factors on time to decannulation. RESULTS: The mean age of the 66 patients who were decannulated was 3.3 ± 1.12 years. Having a chronic neurologic condition was associated with a prolonged time to tracheostomy decannulation (hazard ratio, 0.3; 95% CI, 0.1-0.9), particularly if the patient was not decannulated by 3 years of age. Individuals who had only pulmonary hypertension, required airway reconstruction, or had none of the identified risk factors had similar rates of tracheostomy decannulation. Race, ethnicity, and provider clinical volume were not significantly associated with time to decannulation. CONCLUSIONS: A chronic neurologic condition was the sole factor significantly associated with time to tracheostomy decannulation in our patients with severe BPD. Further work to understand the driving factors for this association will allow clinicians to provide families with more informed guidance as they navigate the complex process of long-term mechanical ventilation.