Segmental Bronchi Research Articles

BRONCHOPLEURAL FISTULA? ENDOBRONCHIAL VALVES TO THE RESCUE

TOPIC: Procedures TYPE: Fellow Case Reports INTRODUCTION: Bronchopleural fistula (BPF) is a sinus tract between the main stem, lobar, or segmental bronchus and the pleural space. Most commonly seen as a complication of lung resection surgery with morbidity ranging from 25%-71%. Treatment of BPF primarily is surgical closure but might but bronchoscopic interventions can be considered in certain cases. Here we present a case of endobronchial valves (EBVs) being used as a bridge to surgery. CASE PRESENTATION: A 60-year-old man presented muscle weakness, anterior mediastinal mass and respiratory failure requiring intubation. Diagnosis of myasthenic crisis was made and he underwent three rounds of plasmapheresis. Subsequently, video assisted thoracoscopy with resection of the thymoma was done but the surgery was complicated with need for right pneumonectomy. On post-operative day 6, patient developed right sided tension pneumothorax requiring a 28 Fr chest tube placement resulting in continuous grade IV air leak. Chest CT scan revealed a right hydropneumothorax (Fig 1). Diagnostic bronchoscopy on day 10, showed absence of right main stem bronchus along with a 4mm bronchopleural fistula (Fig 2). Cultures from the bronchoscopy grew methicillin sensitive staphylococcus aureus and he was started on appropriate antibiotics. He continued to have PAL along with significant tidal volume loss which led to failed weaning on the ventilator. Unfortunately, he was deemed not a surgical candidate due to his ventilator dependence from pneumonia and poor nutritional status. On day 14, we repeated bronchoscopy and fibrin sealant was applied through a guide sheath, down the working channel which reduced the air leak but still persisted. Next day, bronchoscopy with deployment of size 5 spiration endobronchial valves was performed (Fig 3) which led to cessation of air leak and on day 20, patient was successfully weaned off ventilator support. Patient was treated for the empyema for 4 weeks and chest tubes were thereafter removed. He was then discharged to subacute rehabilitation after 57 days of hospitalization and 8 weeks later underwent surgical closure. DISCUSSION: BPF diagnosis and management requires a multidisciplinary approach. Patients with poor cardiopulmonary status, the risks of general anesthesia and surgical intervention pose a challenge. A variety of bronchoscopic options like EBVs, stents, ASD closure devices and occlusive material can be considered, primarily as temporizing measures. EBVs allow retrograde passage of air and infected secretions while blocking anterograde airflow. This reduces or stops the air leak and promotes healing. Their use in our patient allowed for weaning from high levels of oxygen support and liberation from mechanical ventilation. CONCLUSIONS: EBV placement is a minimally invasive procedure which can be performed to help with PAL associated with small BPF (<5mm) when surgery is not an option. REFERENCE #1: M. Lois, M. Noppen, Bronchopleural fistulas: an overview of the problem with special focus on endoscopic management, Chest 128 (2005) 3955–3965. REFERENCE #2: Giddings O, Kuhn J, Akulian J. Endobronchial valve placement for the treatment of bronchopleural fistula: a review of the current literature. Curr Opin Pulm Med. 2014 Jul;20(4):347-51. doi: 10.1097/MCP.0000000000000063. PMID: 24811833. REFERENCE #3: Mahajan AK, Verhoef P, Patel SB, Carr G, Kyle Hogarth D. Intrabronchial valves: a case series describing a minimally invasive approach to bronchopleural fistulas in medical intensive care unit patients. J Bronchology Interv Pulmonol. 2012;19(2):137-141. doi:10.1097/LBR.0b013e318251c897 DISCLOSURES: No relevant relationships by Tejaswi Nadig, source=Web Response

A modified system for classifying the bilateral superior pulmonary veins using three-dimensional computed tomography bronchography and angiography images.

BackgroundIdentifying the distribution of pulmonary veins with three-dimensional reconstruction images is of great significance for surgical guidance. Existing models neglect the consistency of the bilateral superior pulmonary veins (SPVs) and lack a simple unified classification pattern. This study aimed to analyze the distributional features of bilateral SPVs, based on a cohort of patients undergoing CT examination.MethodsThe three-dimensional computed tomography bronchography and angiography (3D-CTBA) images of 1,520 cases were retrospectively analyzed. The reconstructed images of the right upper lobes were read in 715 cases, and left upper lobes in 805 cases. Through symmetrical analysis, the circulation of main venous branches and the spatial relationships of confluences with adjacent bronchus were compared.ResultsThe SPVs of bilateral upper lobes showed common distributional features and were divided into three main types. The central vein type, the semi-central vein type, and the non-central vein type accounted for 83.35% [596], 7.84% [56], 8.11% [58] of the 715 cases with right scanning, and 25.71% [207], 62.61% [504], 10.81% [87] of the 805 cases with left scanning, respectively. There were 5 (0.70%) cases with rare variations in the right upper lobe and 7 (0.87%) in the left upper lobe. The attribution of intersubsegmental vein in the posterior segment (V2b) and its position relative to the anterior segmental bronchus (B3) was the basis of classification in the right upper lobe, and the attribution of intersubsegmental vein in the apicoposterior segment (V1+2c) and its position relative to B3 was the basis of classification in the left upper lobe. In this classification system, the branching pattern of the intersegmental vein between the apical segment and the anterior segment (V1b) in the right upper lobe, and the intersegmental vein between the apicoposterior segment and the anterior segment (V1+ 2a) in the left upper lobe were used for subdivision.ConclusionsOur modified system had a high degree of consistency in classifying SPVs in bilateral upper lobes, thus providing guidance for preoperative and intraoperative procedures.

Three-Dimensional Computed Tomography Bronchography and Angiography-Guided Thoracoscopic Segmentectomy for Pulmonary Nodules.

Three-dimensional computed tomography bronchography and angiography (3D-CTBA) provides detailed imaging information for pulmonary segmentectomy. This study was performed to verify the feasibility of 3D-CTBA-guided thoracoscopic segmentectomy for the treatment of pulmonary nodules. A retrospective analysis was performed on all patients who underwent 3D-CTBA-guided uniport thoracoscopic segmentectomies or subsegmentectomies for pulmonary nodules in the period from May 2019 to May 2020. All of the information related to perioperative management and surgical operations was retrieved from the medical records and operating notes for detailed analysis. A total of 104 eligible operations involving the resection of 110 nodules with diameters in the range of 5-20mm were included. Under 3D-CTBA guidance, the pulmonary nodules were located with an accuracy of 100% (110/110) and the median resection margin was 24.3mm (17-33mm). Additionally, the segmental (subsegmental) bronchi, arteries, and veins were identified with accuracy rates of 100% (104/104), 96.2% (100/104), and 94.2% (98/104), respectively. The postoperative complications consisted of 3 cases of pulmonary infection (2.9%), 6 cases of arrhythmia (5.8%), 2 cases of hemoptysis (1.9%), 4 cases of air leak (3.8%), and 2 cases of subcutaneous emphysema (1.9%). No perioperative death occurred. 3D-CTBA-guided thoracoscopic segmentectomy is an effective surgical approach for the management of pulmonary nodules.

Bronchoscopy and cricothyrotomy: results from cadavers embalmed with Thiel’s method compared to other embalming methods and living subjects

Purpose: Cricothyrotomy and bronchoscopy were performed on cadavers embalmed according to Thiel’s method, and the results compared with findings from other types of cadavers and living subjects, to assess the suitability of such specimens for medical teaching and research.&#x0D; Methods: Blind cricothyrotomy was performed in 40 cadavers using two different devices (Cook and Portex sets) on each of 20 cadavers and the procedures were recorded by a monitoring fibreoptic bronchoscope placed in the larynx. Bronchoscopy was performed on another 22 cadavers. All procedures were videotaped and evaluated by board certified anatomists and anaesthetists. Tissue behaviour, ligament resistance, palpability of anatomical structures, mucosal colour and cadaver flexibility, especially during jaw thrust and tongue lift, were evaluated and qualitatively compared to conditions found in the living and to reports of studies using specimens embalmed with the classic formalin method. Where the procedures caused mucosal lesions, the damaged was assessed during subsequent dissection.&#x0D; Results: The cadavers were life-like in all criteria evaluated. Portex and Cook cricothyrotomy was feasible in all cases. Bronchoscopy was feasible in all cadavers without difficulty. Jaw thrust and tongue lift was never limited and lobar bronchi were always reached. Further advancement was limited in half of the cases by either the preservation liquid or the diameter of the segmental bronchi; in the remaining half, advancement into the smaller airways was limited only by their diameter.&#x0D; Conclusion: Cadavers fixed according to Thiel’s method are highly useable, life-like specimens for teaching and researching cricothyrotomy and bronchoscopy. The data obtained are transferable to the living, so research findings should be valid and teaching effective.

Novel Treatment of Widespread Empyema Necessitatis

A 59-year-old man presented with high fever and tenderness extending from the left side of the chest to the flank. Computed tomography showed a large encapsulated pleural effusion in the left thoracic cavity with subfascial fluid extending from the left chest wall to the abdominal wall (Figure 1). He was diagnosed with empyema necessitatis. The patient developed septic shock and underwent urgent lavage and drainage of the abscess cavity. Because a large bronchopulmonary fistula was detected at the level of the segmental bronchus, temporary closure was considered difficult and fenestration was performed.

A Distinct Difference Between Air and Mucosal Temperatures in Human Respiratory Tract.

Extensive evidence indicates that several types of temperature-sensitive ion channels are abundantly expressed in the sensory nerves innervating airway mucosa. Indeed, airway temperature is known to play an important role in regulating respiratory functions. However, the actual airway mucosal temperature and its dynamic changes during the respiratory cycle have not been directly measured. In previous studies, airway tissue temperature was often estimated by indirect measurement of the peak exhaled breath temperature (PEBT). In view of the poor thermal conductivity of air, we believe that the airway tissue temperature cannot be accurately determined by the exhaled air temperature, and this study aimed to test this hypothesis. We applied a miniature rapid-response temperature probe to measure directly the mucosal temperatures of trachea, major, lobar, and segmental bronchi in eight human subjects during a bronchoscopy procedure. Unlike the air temperature in the airway lumen, the mucosal temperature in these airway segments remained relatively stable and did not exhibit the phasic changes synchronous with respiratory cycles. The airway mucosal temperature increased progressively from the extra-thoracic trachea (35.7 ± 0.2°C) toward the segmental bronchus (36.9 ± 0.2°C). Most importantly, the temperatures measured directly at the mucosa of all these airway segments were substantially higher than the PEBT (31.7 ± 0.8°C). The recent findings of a close association between an increased PEBT and airway tissue inflammation have revealed the implication and potential of incorporating the PEBT measurement in the future clinical diagnosis of airway inflammation. Therefore, it is imperative to recognize this distinct difference in temperature between airway mucosa and exhaled air.

Right apical-posterior segmentectomy with abnormal anterior segmental bronchus and artery: a case report

BackgroundDisplaced anterior segmental bronchus and pulmonary artery is extremely rare. A keen knowledge of such variations is required in the field of pulmonary segmentectomy, for unawareness of the structural variation could lead to intra- and postoperative complications.Case presentationA 50-year-old female presented to our department with suspected lung adenocarcinoma. Preoperative 3-dimensional computed tomographic bronchography and angiography revealed anterior segmental bronchus and anterior segmental pulmonary artery variation: the anterior segmental bronchus derived from the middle lobe bronchus, accompanied by a distally distributed anterior segmental pulmonary artery branch. A right apical-posterior segmentectomy using inflation-deflation technique was performed successfully.ConclusionsThe keen observation and proper application of modern imaging technology and operative technique could greatly aid segmentectomy, preventing intra- and postoperative complications from happening.

Predictors of failure of intersegmental line creation using bronchoscopic jet ventilation for thoracoscopic pulmonary segmentectomy

BackgroundDuring pulmonary segmentectomy, identification of the target segment is essential. We used bronchoscopic jet ventilation (BJV) to delineate the intersegmental plane by selectively sending air into the target segment. The purpose of this study was to investigate the factors associated with BJV failure.MethodsData were retrospectively collected from 48 patients who underwent pulmonary segmentectomy with BJV between March 2014 and May 2019 at a single center. Data were compared between BJV succeeded cases and failed cases.ResultsIn 13 cases (27%), BJV were unsuccessful. The Brinkman index was significantly higher in failed cases (962 ± 965 failed vs. 395 ± 415 successful, P = 0.0067). The success rate was significantly lower when BJV was applied to the posterior basal segmental bronchus (B10) (B10: 1/5 (20%) vs others: 34/43 (79%), P = 0.015).ConclusionLong-term smoking and the bronchus corresponding to the posterior basal segment might make successful performance of BJV difficult.

THE DEVELOPMENT OF BRONCHOPLEURAL FISTULA.

A 66-year-old male with an aspergiloma in the upper left lobe was submitted to a wedge resection in December 2019. Pneumostasis was performed using biological glue and afterward the test of submersion in water showed no significant alveolopleural leak. In the immediate postoperative period, the patient presented an expanded lung parenchyma and moderate alveolopleural leakage that gradually decreased. A month later the patient was readmitted in intensive care unit with an acute respiratory distress after a sudden episode of coughing with abundant and purulent sputum and significant increase in alveolopleural leakage. Intraoperatively it was found that the pulmonary parenchyma covering the segmental bronchi was necrotic.

Characteristics of the Computed Tomography Imaging Findings in 72 Patients with Airway-Invasive Pulmonary Aspergillosis.

BackgroundThis multiple-center retrospective study aimed to investigate computed tomography (CT) imaging findings in 72 patients with airway-invasive pulmonary aspergillosis.Material/MethodsSeventy-two patients with airway-invasive pulmonary aspergillosis confirmed by pathology results were divided into 3 types according to image characteristics. Type I involved the trachea or the main bronchus. Type II involved the lobular and segmental bronchi, which manifested early as bronchial wall thickening, and later development was divided into types IIa and IIb. Type IIa manifested as bronchiectasis, and type IIb manifested as consolidation around the bronchus. Type III involved the bronchioles and pulmonary parenchyma, with tree-in-bud sign and acinar nodules around. CT signs of the various types and their differentiation were investigated.ResultsThe main clinical manifestations of the 72 patients with airway-invasive pulmonary aspergillosis were shortness of breath (55/72, 76.4%), cough (40/72, 55.6%), expectoration (35/72, 48.6%), dyspnea (8/72, 11.1%), weight loss (2/72, 2.8%), and fever (30/72, 41.7%). CT typing identified 3 types: 2 patients (2.8%) had type I, presenting as thickening of trachea or main bronchial walls; 3 patients (4.2%) had early type II, manifesting as thickening of lobular or segmental bronchial walls; 27 patients (37.5%) developed type IIa, manifesting as bronchiectasis; 22 patients (30.6%) had type IIb, manifesting as consolidation around the bronchus; and 18 patients (25.0%) had type III, presenting as nodules and patchy shadows with small cavities in the periphery of the lung.ConclusionsAirway pulmonary aspergillosis has characteristic imaging findings, which can help early clinical diagnosis through classification according to CT imaging characteristics.

Effect of azithromycin on bronchial wall thickness in severe persistent asthma: A double-blind placebo-controlled randomized clinical trial

BackgroundAzithromycin reduced airway remodeling in animal models of asthma. However, its effect on human subjects has not been studied yet. This study aimed to investigate the effect of long-term treatment with azithromycin on airways wall thickness in patients with severe persistent asthma. MethodsIn this randomized, double-blind, placebo-controlled clinical trial, patients with severe persistent asthma received azithromycin (250 mg, BID, three days a week), prednisolone (5 mg, BID), or placebo for eight months in three separate groups in addition to the standard therapy. The improvement in right upper lobe apical segmental bronchus (RB1) wall thickness obtained by high resolution computed tomography was set as the primary outcome. Secondary outcomes included: cough severity, dyspnea severity, asthma control test (ACT) score, asthma exacerbation rate, pulmonary function tests, and fractional exhaled nitric oxide (FENO). ResultsSeventy-eight out of ninety randomized subjects completed eight months of treatment with azithromycin (n = 25), prednisolone (n = 27), or placebo (n = 26). Bronchial wall thickness percentage did not change significantly in any of the groups. However, the inner radius and lumen area of azithromycin and prednisolone-treated subjects increased significantly (p < 0.05 for both). Azithromycin also significantly improved the dyspnea severity, ACT score, FENO, and FEV1, FEF25-75, and FEV1/FVC (p < 0.05 for all). Cough severity or asthma exacerbation rate did not change significantly after eight months of treatment with azithromycin. ConclusionLong-term treatment with azithromycin increased lumen radius and lumen area in patients with severe persistent asthma. However, there was no significant change in wall thickness in any of the treatment groups. Trial registrationIRCT.com (IRCT20091111002695N8).

Radial endobronchial ultrasound-assisted transbronchial needle aspiration for pulmonary peripheral lesions in the segmental bronchi adjacent to the central airway.

BackgroundTissue samples from lesions located in the 3rd to 5th segmental bronchi are challenging to obtain. In this retrospective study, we aimed to evaluate the diagnostic rate of pulmonary peripheral lesions located in the 3rd to 5th segmental bronchi, near the inner field of lung on the computed tomography (CT) image and outside the bronchus, using radial endobronchial ultrasound (REBUS) followed by transbronchial needle aspiration (TBNA).MethodsThis retrospective study enrolled patients whose preoperative CT examinations showed a lesion located in the segmental bronchi (3rd to 5th), yet adjacent to the inner field of lung on the CT image. REBUS followed by TBNA was used to acquire tissue samples from these lesions. A bronchoscope was used to reach the bronchi surrounding the lesion, and an ultrasound probe was used to determine the lesion’s location. Then, the ultrasound probe was withdrawn, and puncture was performed at the location that was determined by ultrasound. The tissue specimens obtained were subjected to pathological examination.ResultsNineteen patients were enrolled in this study including 15 males and 4 females with an average age of 55 years old. Of the enrollees, 8 patients (42.1%) were successfully diagnosed with samples obtained through TBNA, including 6 cases of lung cancer, 1 case of non-specific inflammation, and 1 case of cryptococcal infection. The diagnostic rate was 42.1%. No post-procedural complications were observed among the patients. There was no significant difference in nodule diameter between patients with a diagnostic sample and those in whom TBNA failed to provide a diagnosis (2.99±0.96 vs. 2.26±1.27 cm, P=0.20).ConclusionsWith the assistance of REBUS, TBNA can acquire sufficient samples to achieve a reasonably diagnostic rate for parenchymal lung lesions located near the inner field of lung on the CT image without intrabronchial invasion.

Assessment of Airway Remodeling Using Endobronchial Ultrasound in Asthma-COPD Overlap.

PurposeThe aim of this study was to evaluate the structural changes of the airways using the endobronchial ultrasound (EBUS) in ACO patients compared to severe asthma and COPD patients.Patients and MethodsThe study included 17 patients with ACO, 17 patients with COPD and 33 patients with severe asthma. Detailed clinical data were obtained from all participants. Basic laboratory tests were performed, including measurement of eosinophil counts in blood and serum immunoglobulin E (IgE) concentrations. All patients underwent spirometry and bronchoscopy with EBUS (a 20‑MHz ultrasound probe) to measure the total thicknesses of the bronchial walls and their particular layers in segmental bronchi of the right lower lobe. EBUS allows to distinguish five layers of the bronchial wall. Layer 1 (L1) and layer 2 (L2) were analyzed separately, while the outer layers (layers 3–5 [L3–5]) that correspond to cartilage were assessed together.ResultsIn patients with ACO the thicknesses of the L1 and L2 layers, which are mainly responsible for remodeling, were significantly greater than in patients with COPD and significantly smaller than in patients with severe asthma (median L1= 0.17 mm vs 0.16 mm vs 0.18 mm, p<0.001; median L2= 0.18 mm vs 0.17 mm vs 0.20 mm, p<0.001, respectively). The thicknesses of the total bronchial walls (L1+L2+L3–5) and L3–5 were significantly smaller in ACO and COPD patients compared to asthma patients (median L1+L2+L3–5= 1.2 mm vs 1.14 mm vs 1.31 mm, p<0.001; median L3–5= 0.85 mm vs, 0.81 mm vs 0.92 mm, p=0.001, respectively).ConclusionThe process of structural changes in the airways assessed by EBUS is more advanced in individuals with ACO compared to patients with COPD, and less pronounced compared to patients with severe asthma. It seems that EBUS may provide useful information about differences in airway remodeling between ACO, COPD and severe asthma.

Bronchial Brushing and Diagnosis of Pulmonary Nontuberculous Mycobacteria Infection

Background: The optimal bronchoscopy procedure for diagnosis of pulmonary nontuberculous mycobacteria (NTM) infection is unclear. Objective: This study investigated the usefulness of bronchial brushing in bronchoscopy for diagnosis of pulmonary NTM infection in patients with suspected NTM lung disease and nodular bronchiectasis on chest computed tomography (CT) images. Methods: Bronchoscopy was prospectively performed for 69 patients with clinically suspected pulmonary NTM infection on chest CT from December 2017 through December 2019. Before and after bronchial brushing, bronchial washing was performed with 20 or 40 mL of normal sterile saline at the same segmental or subsegmental bronchi. Before and after bronchial brushing, samples of the washing fluid (pre- and postbrushing samples) and brush deposits (brush samples) were obtained and cultured separately. Results: NTM was detected in 37 of the 69 (53.6%) patients (Mycobacterium avium in 27, Mycobacterium intracellulare in 7, M. abscessus in 2, and M. kansasii in 2). NTM was detected in 34 (49.3%) prebrushing samples, in 27 (39.1%) postbrushing samples, and in 20 (29.0%) brush samples from the 69 patients. In 2 (2.9%) patients, NTM was detected only in postbrushing samples; in 1 (1.4%) patient, NTM was detected only in a brush sample. As compared with bronchial washing only, additional bronchial brushing increased the NTM culture-positive rate by 4.3% (3/69). Bronchial brushing caused bleeding, requiring hemostasis in 5 (7.2%) patients. Conclusion: Additional bronchial brushing increased the NTM culture-positive rate by only 4.3% (3/69), as compared with bronchial washing alone. Thus, the usefulness of brushing appears to be limited.

Multi-scaled Monte Carlo calculation for radon-induced cellular damage in the bronchial airway epithelium

Radon is a leading cause of lung cancer in indoor public and mining workers. Inhaled radon progeny releases alpha particles, which can damage cells in the airway epithelium. The extent and complexity of cellular damage vary depending on the alpha particle’s kinetic energy and cell characteristics. We developed a framework to quantitate the cellular damage on the nanometer and micrometer scales at different intensities of exposure to radon progenies Po-218 and Po-214. Energy depositions along the tracks of alpha particles that were slowing down were simulated on a nanometer scale using the Monte Carlo code Geant4-DNA. The nano-scaled track histories in a 5 μm radius and 1 μm-thick cylindrical volume were integrated into the tracking scheme of alpha trajectories in a micron-scale bronchial epithelium segment in the user-written SNU-CDS program. Damage distribution in cellular DNA was estimated for six cell types in the epithelium. Deep-sited cell nuclei in the epithelium would have less chance of being hit, but DNA damage from a single hit would be more serious, because low-energy alpha particles of high LET would hit the nuclei. The greater damage in deep-sited nuclei was due to the 7.69 MeV alpha particles emitted from Po-214. From daily work under 1 WL of radon concentration, basal cells would respond with the highest portion of complex DSBs among the suspected progenitor cells in the most exposed regions of the lung epithelium.

TGFβ1 Mediates Airway Remodeling Caused by Mechanical Stress during Inspiratory Resistive Breathing

Mechanical stress emerging in the airways during acute or persistent bronchoconstriction is considered to be one of the key mechanisms that may foster airway inflammation and remodeling. TGFβ1is a potent mediator of airway remodeling exerting its pro-fibrotic effect by stimulation of fibroblasts proliferation and enhanced deposition of extracellular matrix. The aim of this study was to investigate the association between airway response to inspiratory resistive breathing, TGFβ1production and severity of airway remodeling. A total of 212 subjects (mean age 47.4±1.10 years, 57% males) including 123 patients with asthma (mostly mild-to moderate) and 89 patients with COPD (GOLD stage II – 53%) were enrolled in the study. All the patients underwent a challenge test with 5-min isocapnic (5% CO2) inspiratory resistive breathing with load at 45% of maximum inspiratory pressure to induce mechanical stress in the airways. Lung function parameters including specific airway conductance (sGaw) were measured before and after the test by body plethysmography. Total TGFβ1was assayed by ELISA in exhaled breath condensate collected before and after the inspiratory resistive breathing. Wall thickness (WT) and area (WA) of the apical (b1) and posterior basal (b10) segmental bronchi were calculated automatically based on CT scans data. We found that 24% of patients responded to experimental mechanical stress by ≥20% reduction in sGaw (group I). At the same time, 18.4% of patients demonstrated ≥20% increase in sGaw after the test (group II). There was no difference in the ratio of high amplitude (≥20%) changes of sGaw between asthma and COPD. However, COPD patients more commonly had low amplitude (<20%) response as compared to asthma (66.3% vs. 51.2%, p=0.03). ΔsGaw negatively correlated with WTb1 (R=-0.16, p=0.04), WAb1 (R=-0.17, p=0.03) and WAb10 (R=-0.17, p=0.03). Group I patients had higher degree of airway remodeling than the patients in group II (WTb1 2.4 (2.1-3.1) mm vs. 2.1 (2.0-2.4) mm, p=0.02; WAb1 69.4 (63.7-75.6)% vs. 63.1 (60.4-67.7)%, p=0.01; WAb10 67.0 (56.0-71.8)% vs. 57.5 (54.9-63.6)%, p=0.03). The changes of TGFβ1level in response to mechanical stress (ΔTGFβ1) significantly correlated with ΔsGaw (R=-0.15, p=0.04). The patients from group I were predominantly characterized by increase in TGFβ1concentration after the test (ΔTGFβ1 8.6 (-13.2-29.8)%) while in group II the level of TGFβ1declined (-12.1 (-30.8-14.3)%, p=0.02). Moreover, the patients with ≥20% increase in TGFβ1after the resistive breathing had more pronounced signs of airway remodeling when compared to those with <20% TGFβ1dynamics (WTb10 2.5 (2.3-2.9) mm vs. 2.3 (2.1-2.7) mm, p=0.04; WAb10 65.7 (58.5-70.8)% vs. 60.2 (54.8-80.5)%, p=0.01). Thus, asthma and COPD patients with ≥20% drop in sGaw in response to 5-min test with inspiratory resistive breathing are more predisposed to airway remodeling. As suggested by the obtained results, this phenomenon is likely mediated by TGFβ1which production is associated both with the decrease in airway conductivity and development of the remodeling.

Demarcation of arteriopulmonary segments: a novel and effective method for the identification of pulmonary segments.

ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy.

Lung segmentectomy assisted by highly selective independent segmental ventilation: a series of three cases

BackgroundThe identification of targeted intersegmental planes and resection with adequate surgical margins are among the crucial steps in anatomical pulmonary segmentectomy, and technical improvements are still needed.Case presentationWe reported three cases of intersegmental plane identification using highly selective independent segmental ventilation during segmentectomy. All cases required cooperation with an anesthesiologist who was able to perform segmental ventilation and double confirmation of segmental bronchus branches by the surgeon. The surgical procedure provides a direct visualization of spare segment inflation and saves time in deflation over the conventional residual segment inflation method.ConclusionsHighly selective independent segmental ventilation could be considered a suitable option for pulmonary intersegmental plane identification and could be universally used for lung segmentectomy.

An intubation catheter integrated with flow sensors and smart actuators for characterizing airflow patterns in stenosed trachea: an objective guide for CAO management

Stenosis reduces the effective lumen area in the tracheal and bronchial segments of the airway anatomy. Loss in patency due to obstruction increases resistance to airflow; thus, severe narrowing is often associated with morbidity and mortality. Etiologies such as congenital tracheal stenosis, tracheomalacia, laryngeal and subglottic stenosis, atresia are few among the many pathologies causing major airway obstruction and respiratory distress. Diagnosis of such anomalies is usually based on clinical suspicion due to the non-specificity of the associated clinical symptoms. Visual assessment using conventional bronchoscopy or radiography images from CT scan for precisely locating obstruction site is highly subject to clinician’s expertise. Characterizing airflow patterns in stenosed airway calls for newer diagnostic tools that can effectively quantify changes in airflow due to construction sites. Our work presents a steerable intubation catheter that can quantitatively measure air velocity across various segments of the tracheobronchial tree. The catheter consists of a three-layer flexible printed circuit board integrated with micro-electro-mechanical system-based thermal flow sensors and a pair of sub-millimeter helical shape memory actuators. Flow distribution is measured in excised sheep tracheal tissues at 15, 30, 50, 65, and 80 l min−1 for normal and stenosed conditions. Even a 10% reduction in lumen area generated unique peaks corresponding to the obstruction site; thus, the catheter can locate stenosis at the precritical stage. For 50% tracheal obliteration, the sensor closest to stenosis showed a 2.4-fold increase in velocity when tested for reciprocating flows. Thus, flow rate scales quadratically with reducing cross-section area, contributing to increased airflow resistance.

Determining Tracheobronchial Tree with Anatomical Dissection: 204 Cases

There are various anatomic variations in the tracheobronchial system. The frequency in studies with bronchoscopy was contradictory. This study aimed to investigate the tracheobronchial tree of the deceased patients with anatomical dissection. We made anatomical dissections on 204 cases in the Council of Forensic Medicine, Ministry of Justice. The deceased patients who were older than 12 years of age and of Turkish origin were included in this study consecutively. Of the 204 cases, 161 (78.9%) were males and 43 (21.1%) were females. The mean age was 44.15±19.23 years. Anatomical variations were found to be present in 200 cases (98% of total). The highest degree of variation of the right upper lobe was noted to be 16.6% (34/204). An anomalous arrangement (with three segments or different placement) of the middle lobe was noted in 16.1% of cases. For the basal lower lobe, b8+(b9+b10) pattern and basal orifice with four segments were noted to be the most frequent anatomical variant in the right and left lungs, respectively. The most frequent tracheobronchial variations were as follows: apical basal lobe with two subsegments in the right and left (39.7%), left lower lobe basal orifice with four segments (34.8%), left upper lobe with three segments (25.5%), and right lower lobe basal orifice with three main segmental bronchi (21.1%). The tracheobronchial tree exhibits highly individualistic features. The knowledge of the frequency of different variations obtained in different studies and normal anatomic variants in return makes doing therapeutic or diagnostic interventions easier and more accurate.