Airway Abnormalities Research Articles

Antenatal Endotoxin Induces Dysanapsis in Experimental Bronchopulmonary Dysplasia.

Bronchopulmonary dysplasia (BPD), the chronic lung disease of prematurity, is characterized by impaired lung development with sustained functional abnormalities due to alterations of airways and the distal lung. Although clinical studies have shown striking associations between antenatal stress and BPD, little is known about the underlying pathogenetic mechanisms. Whether dysanapsis, the concept of discordant growth of the airways and parenchyma, contributes to late respiratory disease as a result of antenatal stress is unknown. We hypothesized that antenatal endotoxin (ETX) impairs juvenile lung function as a result of altered central airway and distal lung structure, suggesting the presence of dysanapsis in this preclinical BPD model. Fetal rats were exposed to intraamniotic ETX (10 μg) or saline solution (control) 2 days before term. We performed extensive structural and functional evaluation of the proximal airways and distal lung in 2-week-old rats. Distal lung structure was quantified by stereology. Conducting airway diameters were measured using micro-computed tomography. Lung function was assessed during invasive ventilation to quantify baseline mechanics, response to methacholine challenge, and spirometry. ETX-exposed pups exhibited distal lung simplification, decreased alveolar surface area, and decreased parenchyma-airway attachments. ETX-exposed pups exhibited decreased tracheal and second- and third-generation airway diameters. ETX increased respiratory system resistance and decreased lung compliance at baseline. Only Newtonian resistance, specific to large airways, exhibited increased methacholine reactivity in ETX-exposed pups compared with controls. ETX-exposed pups had a decreased ratio of FEV in 0.1 second to FVC and a normal FEV in 0.1 second, paralleling the clinical definition of dysanapsis. Antenatal ETX causes abnormalities of the central airways and distal lung growth, suggesting that dysanapsis contributes to abnormal lung function in juvenile rats.

Physiological Characterization of Preserved Ratio Impaired Spirometry in the CanCOLD Study: Implications for Exertional Dyspnea and Exercise Intolerance.

Rationale: It is increasingly recognized that adults with preserved ratio impaired spirometry (PRISm) are prone to increased morbidity. However, the underlying pathophysiological mechanisms are unknown. Objectives: Evaluate the mechanisms of increased dyspnea and reduced exercise capacity in PRISm. Methods: We completed a cross-sectional analysis of the CanCOLD (Canadian Cohort Obstructive Lung Disease) population-based study. We compared physiological responses in 59 participants meeting PRISm spirometric criteria (post-bronchodilator FEV1 < 80% predicted and FEV1/FVC ⩾ 0.7), 264 control participants, and 170 ever-smokers with chronic obstructive pulmonary disease (COPD), at rest and during cardiopulmonary exercise testing. Measurements and Main Results: Individuals with PRISm had lower total lung, vital, and inspiratory capacities than healthy controls (all P < 0.05) and minimal small airway, pulmonary gas exchange, and radiographic parenchymal lung abnormalities. Compared with healthy controls, individuals with PRISm had higher dyspnea/[Formula: see text]o2 ratio at peak exercise (4.0 ± 2.2 vs. 2.9 ± 1.9 Borg units/L/min; P < 0.001) and lower [Formula: see text]o2peak (74 ± 22% predicted vs. 96 ± 25% predicted; P < 0.001). At standardized submaximal work rates, individuals with PRISm had greater Vt/inspiratory capacity (Vt%IC; P < 0.001), reflecting inspiratory mechanical constraint. In contrast to participants with PRISm, those with COPD had characteristic small airways dysfunction, dynamic hyperinflation, and pulmonary gas exchange abnormalities. Despite these physiological differences among the three groups, the relationship between increasing dyspnea and Vt%IC during cardiopulmonary exercise testing was similar. Resting IC significantly correlated with [Formula: see text]o2peak (r = 0.65; P < 0.001) in the entire sample, even after adjusting for airflow limitation, gas trapping, and diffusing capacity. Conclusions: In individuals with PRISm, lower exercise capacity and higher exertional dyspnea than healthy controls were mainly explained by lower resting lung volumes and earlier onset of dynamic inspiratory mechanical constraints at relatively low work rates. Clinical trial registered with www.clinicaltrials.gov (NCT00920348).

Difficult intubation in syndromic versus nonsyndromic forms of micrognathia in children.

We investigated how syndromic versus nonsyndromic forms of micrognathia impacted difficult intubation outcomes in children. Primary outcome was the first-attempt success rate of tracheal intubation, secondary outcomes were number of intubation attempts and complications. We hypothesized that syndromic micrognathia would be associated with lower first-attempt success rate. In micrognathic patients enrolled in the Pediatric Difficult Intubation Registry (08/2012-03/2019) we retrospectively compared demographic and clinical characteristics between children with nonsyndromic and syndromic micrognathia using standardized mean differences (SMD) and assessed the association of the presence of syndrome with the primary and secondary outcomes using propensity score matching analysis with and without matching for airway assessment findings. Nonsyndromic patients (628) were less likely to have additional airway abnormalities. Syndromic patients (216) were less likely to have unanticipated difficult intubation (2% vs. 20%, SMD 0.59). First-attempt success rates of intubation were: 38% in the syndromic versus 34% in the nonsyndromic group (odds ratio [OR] 1.18; 95% confidence intervals [95% CI] 0.74, 1.89; p = .478), and 37% versus 37% (OR 0.99; 95% CI 0.66, 1.48; p = .959). Median number of intubation attempts were 2 (interquartile range [IQR]: 1, 3; range: 1, 8) versus 2 (IQR: 1, 3; range 1, 12) (median regression coefficient = 0; 95% CI: -0.7, 0.7; p = .999) and 2 (IQR: 1, 3; range: 1, 12) versus 2 (IQR: 1, 3; range 1, 8) (median regression coefficient = 0; 95% CI: -0.5, 0.5; p = .999). Complication rates were 14% versus 22% (OR 0.6; 95% CI 0.34, 1.04; p = .07) and 16% versus 21% (OR 0.71; 95% CI 0.43, 1.17; p = .185). Presence of syndrome was not associated with lower first-attempt success rate on intubation, number of intubation attempts, or complication rate among micrognathic patients difficult to intubate, despite more associated craniofacial abnormalities. Nonsyndromic patients were more likely to have unanticipated difficult intubations, first attempt with direct laryngoscopy.

Inadequate (Ax) Transbronchial Lung Transplant Biopsies—Scope and the Potential Contributing Factors

Transbronchial biopsy is the cornerstone for the evaluation of graft function after lung transplant and a standard of care to diagnose acute cellular rejection. However, the yield from these biopsies is variable, with about 15% to 50% of samples being judged as nondiagnostic, leading to additional procedures. The factors contributing to the nondiagnostic sampling have not been delineated, and the discordance in sample assessment between the bronchoscopist and pathologist has not been quantified. A retrospective cohort of patients who had bronchoscopies with biopsies for surveillance and graft assessment at a large-volume transplant center was studied. The occurrence of nondiagnostic alveolar sampling was assessed, and the patient demographics and procedural characteristics were compared with the diagnostic group. We included 128 patients in our study and found the inadequacy rate for alveolar tissue sampling to be 15.5%. The median number of passes made by the bronchoscopist was 9, and the number of samples assessed by the bronchoscopist was 8, with a median of 6 adequate samples identified by the pathologist. The frequency of previous biopsies, history of prior inadequate samples, need for a higher number of pass attempts, presence of airway abnormalities, and the use of general anesthesia increased the odds of inadequate sampling. Patients with the identified factors may be at risk of inadequate sampling on transbronchial biopsies. The bronchoscopist could consider getting additional samples to avoid a nondiagnostic alveolar sample. Further multicenter studies would help to elucidate other contributing factors.

Impulse oscillometry in patients with pulmonary arterial hypertension: an exploratory study

IntroductionStudies suggest peripheral airway abnormalities in Pulmonary Arterial Hypertension (PAH). Impulse Oscillometry (IOS) is a noninvasive and sensitive technique for assessing the small airways. It evaluates the impedance of the respiratory system ‒ Resistance (R) and reactance (X) ‒ to a pulse of sound waves sent to the lungs, in a range of frequencies (5‒20 Hz). MethodResistance variables: R5, R20, R5-R20 and reactance variables: AX (reactance area) and Fres (resonance frequency). The aim is to evaluate R and X in patients with idiopathic PAH (IPAH) and to investigate whether there is a correlation between IOS and spirometry. ResultsThirteen IPAH patients and 11 healthy subjects matched for sex and age underwent IOS and spirometry. IPAH patients had lower FVC and FEV1 values (p < 0.001), VEF1/CVF (p = 0.049) and FEF 25-75 (p = 0.006) than healthy patients. At IOS, IPAH patients showed lower tidal volumes and higher AX (p < 0.05) compared to healthy individuals, and 53.8 of patients had R5-R20 values ≥ 0.07 kPa/L/s. Correlation analysis: X5, AX, R5-R20 and Fres showed moderate correlation with FVC (p = 0.036 r = 0.585, p = 0.001 r = -0.687, p = 0.005 r = -0.726 and p = 0.027 r = -0.610); Fres (p = 0.012 r = -0.669) and AX (p = 0.006 r = -0.711) correlated with FEV1; [R5 and R20, (R5-R20)] also correlated with FEV1 (p < 0.001 r = -0.573, p = 0.020 r = -0.634 and p = 0.010 r = -0.683, respectively) in the IPAH group. There were also moderate correlations of FEF 25–75 % with Z5 (p = 0.041), R5 (p = 0.018), Fres (p = 0.043) and AX (p = 0.023). DiscussionPatients showed changes suggestive of increased resistance and reactance in the IOS compared to healthy individuals, and the IOS findings showed a good correlation with spirometry variables.

Goldenhar syndrome: An ephialte for the anesthesiologist – What we saw was just the tip of the iceberg

Goldenhar syndrome, also called oculoauriculovertebral dysplasia, is characterized by craniofacial, central nervous system, cardiac, renal, and vertebral anomalies. It occurs due to the faulty unilateral development of vertebral arches. Patients presenting for surgery are usually in the pediatric age group. General anesthesia is the preferred mode of anesthesia considering the type of surgery, age of the patient, and vertebral anomaly in this patient group. The first and foremost consideration while anesthetizing these patients is the anticipated difficult airway. Frequently encountered airway abnormalities in these patients are micrognathia, retrognathia, mandibular dysplasia, craniovertebral anomalies leading to limited neck flexion and cervical spine instability, decreased thyromental distance, fascial asymmetry, cleft lip and palate, high arched palate, dental abnormalities, and temporomandibular joint abnormalities. Difficult airways often come disguised as syndromes, and thorough pre-operative evaluation along with preparation for the worst scenarios is a must. We have a myriad of alternative airway management equipment at our disposal. Adequate knowledge is a must for their best use.

Noninvasive Positive Airway Pressure Management for Post-extubation Support in Preterm Infants: Observational Cohort Study with Overlap Weighting Analysis.

Nasal continuous positive airway pressure (NCPAP), nasal intermittent positive pressure ventilation (NIPPV), and high-flow nasal cannula (HFNC) are often used after initial extubation in preterm infants. However, data regarding the choice between NCPAP/NIPPV and HFNC are limited. This study examined which therapy was more effective as post-extubation support. This is a retrospective, cohort study that used the Diagnosis Procedure Combination database in Japan, 2011-2021. Propensity score overlap weighting analyses were performed to compare the composite outcomes of in-hospital death and reintubation in preterm infants who received NCPAP/NIPPV and HFNC. We identified infants born at gestational age 22-36 weeks who were intubated within 1 day of birth. We included patients who underwent NCPAP/NIPPV or HFNC after initial extubation. Patients with airway obstruction or congenital airway abnormalities were excluded. We identified 1,203 preterm infants treated with NCPAP/NIPPV (n = 525) or HFNC (n = 678). The median (interquartile range) gestational age at delivery was 30 (27-33) weeks, and birth weight was 1296 (884-1,802) g. Compared with the HFNC group, the NCPAP/NIPPV group had a significantly lower proportion of the composite outcome after the overlap weighting analysis (risk ratio, 0.62; 95% confidence interval, 0.47 to 0.83; p = 0.001). This significant difference was also observed in infants born at gestational age 22-31 weeks, whereas no significant difference was observed in infants born at gestational age 32-36 weeks. NCPAP/NIPPV may be a superior post-extubation support than HFNC in preterm infants, especially in those born at gestational age of 22-31 weeks.

The Evaluation of Sleep Activity of an Intensive Care Patient Diagnosed with Chronic Obstructive Pulmonary Disease in accordance with NANDA, NIC and NOC : A Case Report

Kronik Obstrüktif Akciğer Hastalığı (KOAH), genellikle zararlı partiküllere maruz kalmakla&#x0D; oluşan havayolu anormalliklerine bağlı kalıcı hava akımı kısıtlaması ve solunumu etkileyen,&#x0D; yaygın, önlenebilir, tedavi edilebilir bir hastalıktır. Morbiditesi ve mortalitesi yüksek düzeyde&#x0D; olan KOAH, dünyada ölüm nedeni sıralamasında 4. sıradadır. KOAH dispne, öksürük,&#x0D; balgam, iştahsızlık, kilo kaybı, halsizlik, uyku sorunları, göğüs ağrısı, anksiyete gibi belirtiler ile&#x0D; yaşam aktivitelerinin kısıtlanmasına neden olmaktadır. KOAH’lı hastalarda solunum aktivitesi&#x0D; sorunları ile birlikte uyku aktivitesi etkilenmekte, uykusuzluk, uykunun bölünmesi gibi&#x0D; problemler ortaya çıkmaktadır. Uyku bozuklukları hastaların yaşam kalitelerinin düşmesine ve&#x0D; hastalık yükünün artmasına neden olmaktadır. İstenen hasta sonuçlarına ulaşmak ve iyileşme&#x0D; süreçlerinin devamlılığı için hemşirelik bakımına olan gereksinimi artıran bu tip karmaşık&#x0D; hastalıkların bakımında, en etkili olan hemşirelik girişimlerinin seçilmesi, uygulanması,&#x0D; değerlendirilmesi hemşirelere klinik karar vermede rehberlik etmektedir. Bu bağlamda, bu&#x0D; olgu sunumunda KOAH hastasının uyku aktivitesine yönelik bakımının NANDA, NIC ve NOC&#x0D; rehberleri doğrultusunda değerlendirilmesi ele alınmıştır.

Predictive value of NLRC3 levels for pulmonary hypertension in patients with chronic obstructive pulmonary disease

Objectives: Chronic obstructive pulmonary disease (COPD) is a medical condition defined by persistent airflow limitation and respiratory symptoms caused by airway and/or alveolar abnormalities. Pulmonary hypertension (PH) is one of the cardiovascular comorbidities associated with COPD. We investigated the correlation of NLRC3 levels in patients with COPD with prognostic and surrogate parameters of PH on echocardiography and examined whether it could be used to predict PH in this patient population. Methods: A total of 80 patients diagnosed with COPD and 40 healthy volunteers as the control group were included in the study. The COPD group was further divided into two subgroups according to the systolic pulmonary artery pressure (sPAP) as follows: sPAP&amp;lt;35 mmHg and sPAP≥35 mmHg. The enzyme-linked immunosorbent assay (ELISA) method was used to determine the levels of NLRC3 in peripheral blood. Results: Patients with sPAP≥35 mmHg had a lower mean NLRC3 level than those with sPAP&amp;lt;35 mmHg (P=0.006). The NLRC3 levels showed a significant negative correlation with sPAP, tricuspid regurgitation velocity, right atrium, and pulmonary artery diameter. For NLRC3, the cut-off value was found to be 271,486 ng/L, with a sensitivity of 74%, and specificity of 63% in distinguishing patients with sPAP≥35 mmHg from all patients with sPAP&amp;lt;35 mmHg. Conclusions: Our study results suggest that NLRC3 levels measured from peripheral blood are predictive of PH in patients with COPD. Although the exact function of NLRC3 in the lungs, COPD, and PH have not been completely understood, we believe these findings will serve as a model for future studies.

Clinical phenotype of FOXP1 syndrome: parent-reported medical signs and symptoms in 40 individuals

BackgroundThe first studies on patients with forkhead-box protein P1 (FOXP1) syndrome reported associated global neurodevelopmental delay, autism symptomatology, dysmorphic features and cardiac and urogenital malformations. The aim of this study...

Children with severe asthma have substantial structural airway changes on computed tomography.

In adults with severe asthma (SA) bronchial wall thickening, bronchiectasis and low attenuation regions (LAR) have been described on chest computed tomography (CT) scans. The extent to which these structural abnormalities are present in children with SA is largely unknown. Our aim was to study the presence and extent of airway abnormalities on chest CT of children with SA. 161 inspiratory and expiratory CT scans, either spirometer-controlled or technician-controlled, obtained in 131 children with SA (mean±SD age 11.0±3.8 years) were collected retrospectively. Inspiratory scans were analysed manually using a semi-quantitative score and automatically using LungQ (v2.1.0.1; Thirona B.V., Nijmegen, the Netherlands). LungQ segments the bronchial tree, identifies the generation for each bronchus-artery (BA) pair and measures the following BA dimensions: outer bronchial wall diameter (Bout), adjacent artery diameter (A) and bronchial wall thickness (Bwt). Bronchiectasis was defined as Bout/A ≥1.1, bronchial wall thickening as Bwt/A ≥0.14. LAR, reflecting small airways disease (SAD), was measured automatically on inspiratory and expiratory scans and manually on expiratory scans. Functional SAD was defined as FEF25-75 and/or FEF75 z-scores <-1.645. Results are shown as median and interquartile range. Bronchiectasis was present on 95.8% and bronchial wall thickening on all CTs using the automated method. Bronchiectasis was present on 28% and bronchial wall thickening on 88.8% of the CTs using the manual semi-quantitative analysis. The percentage of BA pairs defined as bronchiectasis was 24.62% (12.7-39.3%) and bronchial wall thickening was 41.7% (24.0-79.8%) per CT using the automated method. LAR was observed on all CTs using the automatic analysis and on 82.9% using the manual semi-quantitative analysis. Patients with LAR or functional SAD had more thickened bronchi than patients without. Despite a large discrepancy between the automated and the manual semi-quantitative analysis, bronchiectasis and bronchial wall thickening are present on most CT scans of children with SA. SAD is related to bronchial wall thickening.

Incidentally discovered tracheal bronchus.

Congenital anomalies of the large airways are occasionally asymptomatic and are incidentally discovered through radiography, often using computed tomography. Bronchoscopy can aid in the direct visual examination of the large airway abnormalities detected on radiography.

Nager Syndrome Co-Harboring Mutation Consistent with Stickler Syndrome: A Rare Case Report

Nager syndrome, or preaxial acrofacial dysostosis, is a rare malformation characterized by abnormalities of the craniofacial skeleton and limbs. Although most cases are sporadic and some cases have been demonstrated to have an autosomal dominant or recessive mode of inheritance, SF3B4 haploinsufficiency is the most common genetic abnormality identified in this, of which only around 100 cases have been reported so far in the literature. Classically characterized by ante-mongoloid slant, retrognathia, midface retrusion and proximal limb abnormalities like thumb aplasia or hypoplasia, arachnodactyly and radioulnar synostosis, the significant morbidity and mortality in this challenging condition is primarily due to airway abnormalities causing respiratory obstruction. We report a case of genetically confirmed Nager syndrome simultaneously harbouring a mutation consistent with Stickler syndrome type II.

Repurposing catheter ablation work-up to detect expiratory airflow limitation in patients with atrial fibrillation

BackgroundIn atrial fibrillation (AF) patients, presence of expiratory airflow limitation may negatively impact treatment outcomes. AF patients are not routinely screened for expiratory airflow limitation, but existing examinations can help identify at-risk individuals. We aimed to assess the diagnostic value of repurposing existing assessments from the pre-ablation work-up to identify and understand the characteristics of affected patients. MethodsWe screened 110 consecutive AF patients scheduled for catheter ablation with handheld spirometry. Routine pre-ablation work-up included cardiac computed tomographic angiography (CCTA), transthoracic echocardiography and polygraphy. CCTA was analyzed qualitatively for emphysema and airway abnormalities. Multivariate logistic regression analysis was performed to determine predictors of expiratory airflow limitation. ResultsWe found that 25 % of patients had expiratory airflow limitation, which was undiagnosed in 86 % of these patients. These patients were more likely to have pulmonary abnormalities on CCTA, including emphysema (odds ratio [OR] 4.2, 95 % confidence interval [CI] 1.12–15.1, p < 0.05) and bronchial wall thickening (OR 2.6, 95 % CI 1.0–6.5, p < 0.05). The absence of pulmonary abnormalities on CCTA accurately distinguished patients with normal lung function from those with airflow limitation (negative predictive value: 85 %). Echocardiography and polygraphy did not contribute significantly to identifying airflow limitation. ConclusionsIn conclusion, routine pre-ablation CCTA can detect pulmonary abnormalities in AF patients with airflow limitation, guiding further pulmonary assessment. Future studies should investigate its impact on ablation procedure success.

Findings on drug-induced sleep endoscopy in infants with laryngomalacia

IntroductionObstructive sleep apnea (OSA) is highly prevalent in infants with laryngomalacia (LM). Previous studies have reported high rates of persistent OSA following supraglottoplasty (SGP). The objective of this study is to describe the findings on drug-induced sleep endoscopy (DISE) in infants with LM. MethodsA retrospective review was performed including infants (12.5 months of age or less) with LM who underwent DISE along with direct laryngoscopy and bronchoscopy (DLB). Data collected included clinical presentation, swallow study results, sleep study results, past medical and surgical history, and postoperative outcomes when follow-up data was available. The findings on DISE as well as DLB were reviewed and described. ResultsThirty-five infants were included in the study with a mean age of 0.42 years (range 0.04–1.04). Obstructive sleep-disordered breathing (oSDB) and/or OSA were identified in 26 patients (74.3%) in addition to 7 patients (20%) with noisy breathing during sleep. DISE demonstrated LM in 31 patients (89%). DISE identified 12 patients (34%) with partial or complete obstruction at the level of the tongue base. DLB identified 14 patients (40%) with a secondary airway abnormality including 7 patients (20%) with type 1 laryngeal cleft and 4 patients (11%) with grade 1 subglottic stenosis. Eighteen patients (51%) underwent SGP. ConclusionDISE at the time of airway endoscopy for infants with LM can be helpful in identifying additional sites of obstruction including the tongue base. Glossoptosis may explain and/or predict the previously reported persistence of OSA following SGP. Additionally, DISE can complement awake flexible laryngoscopy in the assessment of severity of LM.

Incidence of Airway Abnormalities in Children With Craniosynostosis.

Children with syndromic craniosynostosis are known to have a high propensity for associated airway abnormalities. However, this has not been investigated using a large-scale national database. For this retrospective cohort study, the 2016 Healthcare Cost and Utilization Project Kid's Inpatient Database was queried for craniosynostosis patients. Data on demographics, airway diagnoses, and comorbidities were analyzed. Four thousand nine hundred fourteen children with craniosynostosis with a mean age of 1.7±3.6 years were identified. Of these, 51% were female and 136 children had an associated syndrome. Choanal atresia was present in 31% of patients with an associated syndrome versus 2.5% without. Syndromic patients are 4.59 times more likely (95% CI 2.65-7.94) to have airway anomalies than nonsyndromic patients. After age and sex adjustment, craniosynostosis patients have higher likelihoods of presenting with other anomalies, with syndromic having higher incidences: 5.23 times (95% CI 2.63-10.39) more likely to have laryngomalacia, 18.30 times (95% CI 3.27-102.36) more likely to have tracheal stenosis, and 4.58 times (95% CI 1.36- 15.43) more likely to have tracheomalacia. Incidence of tracheostomy was 5.84 times (95% CI 3.77-9.04) higher in syndromic patients with craniosynostosis. Tracheostomy rates were 28.4% and 4.6% in craniosynostosis patients with and without associated syndrome, respectively. Syndromic craniosynostosis patients had significantly higher incidences of choanal atresia and other airway anomalies. Given a high incidence of airway anomalies, syndromic craniosynostosis patients likely warrant routine airway evaluation. Providers should also be vigilant about airway evaluation in patients with nonsyndromic craniosynostosis when aerodigestive symptoms arise.

An ex vivo rat trachea model reveals abnormal airway physiology and a gland secretion defect in cystic fibrosis.

Cystic fibrosis (CF) is a genetic disease hallmarked by aberrant ion transport that results in delayed mucus clearance, chronic infection, and progressive lung function decline. Several animal models have been developed to study the airway anatomy and mucus physiology in CF, but they are costly and difficult to maintain, making them less accessible for many applications. A more available CFTR-/- rat model has been developed and characterized to develop CF airway abnormalities, but consistent dosing of pharmacologic agents and longitudinal evaluation remain a challenge. In this study, we report the development and characterization of a novel ex vivo trachea model that utilizes both wild type (WT) and CFTR-/- rat tracheae cultured on a porcine gelatin matrix. Here we show that the ex vivo tracheae remain viable for weeks, maintain a CF disease phenotype that can be readily quantified, and respond to stimulation of mucus and fluid secretion by cholinergic stimulation. Furthermore, we show that ex vivo tracheae may be used for well-controlled pharmacological treatments, which are difficult to perform on freshly excised trachea or in vivo models with this degree of scrutiny. With improved interrogation possible with a durable trachea, we also established firm evidence of a gland secretion defect in CFTR-/- rat tracheae compared to WT controls. Finally, we demonstrate that the ex vivo tracheae can be used to generate high mucus protein yields for subsequent studies, which are currently limited by in vivo mucus collection techniques. Overall, this study suggests that the ex vivo trachea model is an effective, easy to set up culture model to study airway and mucus physiology.

Risk of dysphagia in a population of infants born pre-term: characteristic risk factors in a tertiary NICU

ObjectiveTo examine the prevalence and characteristics of dysphagia and suck-swallow-breath incoordination as phenotypes of oral feeding difficulties. MethodA cross-sectional study with secondary data collected consecutively over 2 years from October 2020 to October 2022 to measure the prevalence of swallowing and oral feeding difficulty in preterm infants using Flexible endoscopic evaluation of swallowing examination at the tertiary Integrated Dysphagia Clinic. ResultsThe prevalence of swallowing disorders was 25 % and the prevalence of suck-swallow-breath incoordination was 62.5 %. The significant risk factor that may show a possible correlation with oral feeding difficulty was mature post-menstrual age (p = 0.006) and longer length of stay (p = 0.004). The dominant percentage of upper airway abnormality and disorder were retropalatal collapse (40 %), laryngomalacia (42.5 %), paradoxical vocal cord movement (12.5 %), and gastroesophageal reflux disease (60 %). The dominant characteristic of oral motor examination and flexible endoscopic evaluation of swallowing examination was inadequate non-nutritive sucking (45 %), inadequate postural tone (35 %), and inadequate nutritive sucking (65 %). ConclusionDysphagia in preterm infants is mostly observed in those with mature post-menstrual age, longer length of stay, and the presence of gastroesophageal reflux disease with inadequate non-nutritive sucking and nutritive sucking abilities. Suck-swallow-breath incoordination is primarily observed in those with immature post-menstrual age, a higher prevalence of cardiopulmonary comorbidity, and a higher prevalence of upper airway pathologies (laryngomalacia, paradoxical vocal cord movement) with inadequate nutritive sucking ability.

Factors Associated With Post-Extubation Stridor in Infants Intubated in the Pediatric ICU.

Post-extubation stridor (PES) is a common problem in the pediatric intensive care unit (PICU) and is associated with extubation failure, longer length of stay, and increased mortality. Infants represent a large proportion of PICU admissions and are at higher risk for PES, making identification and mitigation of factors associated with PES important in this age group. What factors are associated with PES in infants (age less than 1 year) intubated in the PICU? The primary outcome was PES as defined by the need for racemic epinephrine within 6 h of extubation. Secondary outcomes were heliox administration and reintubation. Statistical analyses were performed with Fisher's exact test for univariate analyses and multivariate logistic regression. 518 patient charts were retrospectively reviewed. 24.1% of patients developed PES. Duration of mechanical ventilation greater than 48 h was associated with increased risk of PES (odds ratio [OR] = 1.75, 95% confidence interval [CI] 1.13-2.71, P = .01), as was nonelective intubation (OR = 2.92, 95% CI 1.91-4.46, P < .01). The presence of a cuff, gastroesophageal reflux disease, prematurity, and known upper airway abnormality had no association with PES. 4.0 endotracheal tubes (ETTs) had an increased association with PES compared to 3.5 ETTs (OR = 1.96, 95% CI 1.18-3.27, P < .01). There was no difference in risk of PES between 3.5 and 3.0 ETTs. In infants intubated in the PICU, mechanical ventilation greater than 48 h and nonelective intubation were associated with PES. 4.0 ETTs were associated with higher risk of PES compared to 3.5 ETTs. These findings may help providers in ETT selection and to identify infants that may be at increased risk of PES.

Automated detection of abnormal respiratory sound from electronic stethoscope and mobile phone using MobileNetV2

Auscultation, a traditional clinical examination method using a stethoscope to quickly assess airway abnormalities, remains valuable due to its real-time, non-invasive, and easy-to-perform nature. Recent advancements in computerized respiratory sound analysis (CRSA) have provided a quantifiable approach for recording, editing, and comparing respiratory sounds, also enabling the training of artificial intelligence models to fully excavate the potential of auscultation. However, existing sound analysis models often require complex computations, leading to prolonged processing times and high calculation and memory requirements. Moreover, the limited diversity and scope of available databases limits reproducibility and robustness, mainly relying on small sample datasets primarily collected from Caucasians. In order to overcome these limitations, we developed a new Chinese adult respiratory sound database, LD-DF RSdb, using an electronic stethoscope and mobile phone. By enrolling 145 participants, 9,584 high quality recordings were collected, containing 6,435 normal sounds, 2,782 crackles, 208 wheezes, and 159 combined sounds. Subsequently, we utilized a lightweight neural network architecture, MobileNetV2, for automated categorization of the four types of respiratory sounds, achieving an appreciable overall performance with an AUC of 0.8923. This study demonstrates the feasibility and potential of using mobile phones, electronic stethoscopes, and MobileNetV2 in CRSA. The proposed method offers a convenient and promising approach to enhance overall respiratory disease management and may help address healthcare resource disparities.