[Management of Tracheobronchial Injuries due to Brunt Trauma].

BACKGROUND: Tracheobronchial injuries resulting from blunt trauma are relatively rare among chest injuries. However, if these injuries are not managed properly, they can be fatal. The prognosis is intricately linked to the precise diagnosis and treatment. We herein report three cases of tracheobronchial trauma that required surgical intervention. Case 1:A 17-year-old male sustained injuries when his torso became entangled in heavy machinery. The diagnosis revealed a tear in the right main bronchus, which required transportation with left single- lung ventilation. The patient was treated by tracheobronchial reconstruction. Case 2:A 71-year-old male experienced trauma when his car collided with a utility pole. He was transported to the hospital after tracheal intubation due to a laceration of the tracheal membranous area. The site of the injury was closed with sutures. Case 3:A 17-year-old female who had been struck by a train suffered acute respiratory failure and was transported to the hospital after intubation. Veno-venous extracorporeal membrane oxgenation (VV-ECMO) was initiated in response to poor oxygenation. Complete rupture of the right middle bronchial trunk and laceration of the right main bronchial membrane were observed, and bronchoplasty was performed. CONCLUSION: A swift and accurate diagnosis, coupled with timely and judicious therapeutic interventions, play a pivotal role in managing tracheal and bronchial injuries.

Fractured Metallic Tracheostomy Tube: A Rare Presentation of Bronchial Foreign Body.

BACKGROUND: Tracheostomy is an important life-saving surgical procedure that could be used to secure the lower airway. It can however serve as a source of airway compromise when fragments from it are deposited. This condition must be diagnosed early enough, and appropriate intervention should be done to forestall potential morbidity and mortality. CASE REPORT: A 56-year-old tracheostomized patient presented to the accident and emergency department with a 4-hour history of sudden onset choking cough and labored breathing. The shaft of his tracheostomy tube (TT) was fractured and subsequently aspirated while he was attempting to remove and clean the inner tube that morning. He has used the TT for about 6 years and lost to follow-up clinic visits. The chest radiograph showed the metallic foreign body lodged within the trachea. He had an emergency rigid bronchoscopy via the tracheostomy stoma, and the object was retrieved. All respiratory symptoms subsequently resolved, and a check radiograph showed normal findings. CONCLUSION: Tracheostomy tube fracture and aspiration should be ruled out in every tracheostomized patient with sudden onset acute respiratory symptoms. Otolaryngologists must always emphasize the need for proper handling of TT, regular follow-up, and tube replacement when due.

Primary repair of a completely ruptured intermediate bronchus after blunt chest trauma. Case report.

BACKGROUND: Tracheobronchial injury is rare and often has a fatal course. The incidence is estimated from 0.8% to 5% in the scenario of blunt or penetrating chest trauma. CASE PRESENTATION: A 54-year-old male was brought to the emergency department after falling off his bicycle, with impact on head and right shoulder. At pre-hospital assessment, the patient had a free airway, gasping respiration (oxygen saturation 92%) with reduced vesicular breathing. Multiple rib fractures are palpable bilaterally, with subcutaneous emphysema. Computed tomography (CT) showed a large right-sided pneumothorax and consolidated lung lobes. After insertion of two chest tubes on the right, a refractory pneumothorax with large air leakage remained present. Subsequently, a bronchoscopy was performed, confirming a complete rupture of the right intermediate bronchus. Urgent surgical debridement and primary repair with an end-to-end running suture was performed. Rib osteosynthesis was additionally performed bilaterally, because of a flail chest on the right side and penetrating bone fragment on the left side. Respiratory function recovered uneventfully. CONCLUSION: Airway injuries are uncommon but must always be suspected by the clinician during the early management of chest trauma. To prevent delayed diagnosis and potentially fatal outcome, low-threshold bronchoscopy is the diagnostic modality of choice to accurately confirm the lesion. Primary surgical repair remains the mainstay of the therapeutic management.

Emergency repair of blunt traumatic bronchus injury presenting with massive air leak.

Blunt traumatic tracheobronchial injury is rare, but can be potentially life-threatening. It accounts for only 0.5%-2% of all trauma cases. Patients may present with non-specific signs and symptoms, requiring a high index of suspicion with accurate diagnosis and prompt treatment. A 26-year-old female was brought into the emergency department after sustained a blunt trauma to the chest from a high impact motor vehicle accident. She presented with signs of respiratory distress and extensive subcutaneous emphysema from the chest up to the neck. Her airway was secured and chest drain was inserted for right sided pneumothorax. CT of the neck and thorax revealed a collapsed right middle lung lobe with a massive pneumothorax, raising the suspicion of a right middle lobe bronchus injury. Diagnosis was confirmed by bronchoscopy. In view of the difficulty in maintaining her ventilation and persistent pneumothorax with a massive air leak, immediate right thoracotomy via posterolateral approach was performed. The right middle lobar bronchus tear was repaired. There were no intra- or post-operative complications. She made an uneventful recovery. She was asymptomatic at her first month follow-up. A repeated chest X-ray showed expanded lungs. Details of the case including clinical presentation, imaging and management were discussed with an emphasis on the early uses of bronchoscopy in case of suspected blunt traumatic tracheobronchial injury. A review of the current literature of tracheobronchial injury management was presented.

Dynamic Expression of Transient Receptor Potential Vanilloid-3 and Integrated Signaling with Growth Factor Pathways during Lung Epithelial Wound Repair following Wood Smoke Particle and Other Forms of Lung Cell Injury.

Prior studies revealed increased expression of the transient receptor potential vanilloid-3 (TRPV3) ion channel after wood smoke particulate matter (WSPM) treatment of human bronchial epithelial cells (HBECs). TRPV3 attenuated pathologic endoplasmic reticulum stress and cytotoxicity mediated by transient receptor potential ankyrin-1. Here, the basis for how TRPV3 expression is regulated by cell injury and the effects this has on HBEC physiology and WSPM-induced airway remodeling in mice was investigated. TRPV3 mRNA was rapidly increased in HBECs treated with WSPM and after monolayer damage caused by tryptic disruption, scratch wounding, and cell passaging. TRPV3 mRNA abundance varied with time, and stimulated expression occurred independent of new protein synthesis. Overexpression of TRPV3 in HBECs reduced cell migration and wound repair while enhancing cell adhesion. This phenotype correlated with disrupted mRNA expression of ligands of the epidermal growth factor, tumor growth factor-ß, and frizzled receptors. Accordingly, delayed wound repair by TRPV3 overexpressing cells was reversed by growth factor supplementation. In normal HBECs, TRPV3 upregulation was triggered by exogenous growth factor supplementation and was attenuated by inhibitors of growth factor receptor signaling. In mice, subacute oropharyngeal instillation with WSPM also promoted TRPV3 mRNA expression and epithelial remodeling, which was attenuated by TRPV3 antagonist pre- and cotreatment. This latter effect may be the consequence of antagonist-induced TRPV3 expression. These findings provide insights into the roles of TRPV3 in lung epithelial cells under basal and dynamic states, as well as highlight potential roles for TRPV3 ligands in modulating epithelial damage/repair. SIGNIFICANCE STATEMENT: Coordinated epithelial repair is essential for the maintenance of the airways, with deficiencies and exaggerated repair associated with adverse consequences to respiratory health. This study shows that TRPV3, an ion channel, is involved in coordinating repair through integrated repair signaling pathways, wherein TRPV3 expression is upregulated immediately after injury and returns to basal levels as cells complete the repair process. TRPV3 may be a novel target for understanding and/or treating conditions in which airway/lung epithelial repair is not properly orchestrated.

Migration of ingested sharp foreign body into the bronchus: a case report and review of the literature.

BACKGROUND: Foreign body ingestion is a common emergence in gastroenterology. Foreign bodies are most likely to be embedded in the esophagus. The sharp ones may penetrate the esophageal wall and lead to serious complications. CASE PRESENTATION: A 72-year-old Chinese female was admitted to our hospital with a 4-day history of retrosternal pain and a growing cough after eating fish. Chest computed tomography scan indicated that a high-density foreign body (a fish bone) penetrated through the esophageal wall and inserted into the left main bronchus. First, we used a rigid esophagoscope to explore the esophagus under general anesthesia. However, the foreign body was invisible in the side of the esophagus. Then, the fiberoptic bronchoscopy was performed. We divided the fish bone, which traversed the left main bronchus, into two segments under holmium laser and removed the foreign body successfully. The operation time was short and there were no complications. The patient was discharged 1 week postoperatively and was symptom free even under a liquid diet. CONCLUSIONS: There are several challenges in the management of this rare condition. We applied the technique of interventional bronchoscopy to the management of esophageal foreign body flexibly in an emergency. A surgery was avoided, which was more invasive and costly.

Bronchial rupture following endobronchial blocker placement: a case report of a rare, unfortunate complication.

BACKGROUND: Lung separation may be achieved through the use of double lumen tubes or endobronchial blockers. The use of lung separation techniques carries the risk of airway injuries which range from minor complications like postoperative hoarseness and sore throat to rare and potentially devastating tracheobronchial mucosal injuries like bronchus perforation or rupture. With few case reports to date, bronchial rupture with the use of endobronchial blockers is indeed an overlooked complication. CASE PRESENTATION: A 78-year-old male patient with a left upper lobe lung adenocarcinoma underwent a left upper lobectomy with a Fuji Uniblocker® as the lung separation device. Despite an atraumatic insertion and endobronchial blocker balloon volume within manufacturer specifications, an intraoperative air leak developed, and the patient was found to have sustained a left mainstem bronchus rupture which was successfully repaired and the patient extubated uneventfully. Unfortunately, the patient passed on in-hospital from sepsis and other complications. CONCLUSION: Bronchial rupture is a serious complication of endobronchial blocker use that can carry significant morbidity, and due care should be exercised in its use and placement. Bronchoscopy should be used during insertion, and the volume and pressure of the balloon kept to the minimum required to prevent air leak. Bronchial injury should be considered as a differential in the presence of an unexplained air leak.

Tracheobronchial Slough, a Potential Pathology in Endotracheal Tube Obstruction in Patients With Coronavirus Disease 2019 (COVID-19) in the Intensive Care Setting.

BACKGROUND: A novel coronavirus (COVID-19) erupted in the latter part of 2019. The virus, SARS-CoV-2 can cause a range of symptoms ranging from mild through fulminant respiratory failure. Approximately 25% of hospitalized patients require admission to the intensive care unit, with the majority of those requiring mechanical ventilation. High density consolidations in the bronchial tree and in the pulmonary parenchyma have been described in the advanced phase of the disease. We noted a subset of patients who had a sudden, significant increase in peak airway, plateau and peak inspiratory pressures. Partial or complete ETT occlusion was noted to be the culprit in the majority of these patients. METHODS: With institutional IRB approval, we examined a subset of our mechanically ventilated COVID-19 patients. All of the patients were admitted to one of our COVID-19 ICUs. Each was staffed by a board certified intensivist. During multidisciplinary rounds, all arterial blood gas (ABG) results, ventilator settings and ventilator measurements are discussed and addressed. ARDSNet Protocols are employed. In patients with confirmed acute occlusion of the endotracheal tube (ETT), acute elevation in peak airway and peak inspiratory pressures are noted in conjunction with desaturation. Data was collected retrospectively and demographics, ventilatory settings and ABG results were recorded. RESULTS: Our team has observed impeded ventilation in intubated patients who are several days into the critical course. Pathologic evaluation of the removed endotracheal tube contents from one of our patients demonstrated a specimen consistent with sloughed tracheobronchial tissues and inflammatory cells in a background of dense mucin. Of 110 patients admitted to our adult COVID-19 ICUs, 28 patients required urgent exchange of their ETT. CONCLUSION: Caregivers need to be aware of this pathological finding, recognize, and to treat this aspect of the COVID-19 critical illness course, which is becoming more prevalent.

Imaging Evaluation of Tracheobronchial Injuries.

Tracheobronchial injuries are a rare but potentially life-threatening cause of respiratory insufficiency, with high mortality rates. For patients with potentially survivable tracheobronchial injuries, imaging in the acute setting plays a key role in demonstrating the injuries and associated complications. The radiologist can improve outcomes by understanding typical injury patterns according to injury mechanism and the influence that imaging findings may have on treatment decisions. Chest radiography and cervical and thoracic CT are the mainstays of imaging in the acute setting and in follow-up, often as part of a whole-body trauma imaging series. The authors first consider the influence of normal tracheobronchial anatomy with regard to protective features, such as cartilaginous rings. They also discuss inherent points of vulnerability, such as points of relative fixation at the carina. A framework is then provided for understanding the typical distribution and morphology of tracheobronchial injuries according to cause. This includes penetrating, iatrogenic, and blunt force mechanisms, with consideration of potential complications. The authors highlight treatment strategies that require multidisciplinary collaboration, such as ventilation, minimizing injuries, and defining optimal surgical or nonsurgical treatment. ©RSNA, 2020.

Steam induced by the activation of energy devices under a wet condition may cause thermal injury.

BACKGROUND: During esophagectomy for esophageal cancer, meticulous attention is needed to prevent thermal injury to the vital organs, such as the recurrent laryngeal nerve (RLN) and tracheobronchus. In order to clarify the novel mechanism behind thermal injury induced by energy devices, we investigated the temperature of steam with the use of two different devices under wet and dry conditions. METHODS: An ultrasonic device (Sonicision™) and a vessel sealing device (Ligasure™) were studied. We evaluated the temperature at the tip of the devices and the steam when the devices were activated under different grasping ranges, under four different combinations of device and muscle, and under four different wet/dry conditions (dry-dry, dry-wet, wet-dry, and wet-wet). RESULTS: Although the maximum temperature of the devices was significantly higher with Sonicision™ than with Ligasure™, the maximum temperature of the steam was significantly higher with Ligasure™ than with Sonicision™ in almost all situations. At 1 mm away from Sonicision™, the critical temperature more than 60 °C was observed only when used with one-third grasping range under the wet-dry or the wet-wet conditions. In case of Ligasure™, high-temperature steam was observed when used with one-third grasping under the wet-dry or the wet-wet condition and two-third grasping under the dry-wet, the wet-dry, or the wet-wet condition. Under the wet condition, the emission of steam from the non-grasping part of Ligasure™ caused a spike in temperature that exceeded the critical temperature. CONCLUSION: We demonstrated that the use of energy devices under a wet condition generates steam from the non-grasping part of the devices. The temperatures of steam from Ligasure™ were significantly higher than that from Sonicision™. To prevent thermal injury to the vital organs, a very attentive and meticulous surgical technique is imperative considering the characteristics of each device.

Occult foreign body aspirations in pediatric patients: 20-years of experience.

BACKGROUND: The purpose of our study was to assess the frequency of occult foreign body aspiration (FBA) and to evaluate the diagnostic difficulties and therapeutic methods for these patients. METHODS: Between May 2000 and May 2020, 3557 patients with the diagnosis of FBA were treated in our department. Thirty-five patients with occult FBA were included in this study. A retrospective analysis of medical records was performed. RESULTS: Twenty-three male patients (65.7%) and 12 female patients (34.3%) were hospitalized due to occult FBA. The average age was 3.60 years (range 9 months-12 years). Most of the patients were younger than 3 years old (n = 25, 71.4%). Coughing (n = 35, 100%) and wheezing (n = 18, 51.4%) were the main symptoms and signs. All the patients were found to have a FBA under the fiberoptic bronchoscope. The most common organic foreign bodies were peanuts (n = 10) and the most common inorganic foreign bodies were pen caps (n = 5). The extraction of foreign bodies under rigid bronchoscopy was applied successfully in 34 patients. Only one patient needed a surgical intervention. CONCLUSIONS: Occult FBA should always be considered in the differential diagnosis of chronic or recurrent respiratory diseases that are poorly explained, even in the absence of a previous history of aspiration.

Experience of diagnosis and treatment of traumatic bronchial rupture in children in a single clinical center.

PURPOSE: To examine the diagnosis and treatment of traumatic bronchial rupture in children at the Children's Hospital of Chongqing Medical University, Chongqing, China. METHODS: The diagnosis and treatment of eight cases of traumatic bronchial rupture were analyzed retrospectively from January 2014 to December 2019 in our hospital. RESULTS: Diagnosis of the eight patients was clear after a chest CT with three-dimensional reconstruction techniques and fiberoptic bronchoscopy; six of the patients had a delay in diagnosis of at least 2 weeks. Among the patients, six had left bronchus rupture, and the other two had right bronchus rupture. All eight patients received surgery; seven patients received a bronchial end-to-end valgus anastomosis, and one received right middle lobe lobectomy. There were no deaths in this group, and all patients were cured and discharged. Follow-up was conducted for 3 months to 2 years; the patients who received surgery showed mild bronchostenosis within 2 weeks after the trauma, and the other six patients showed moderate bronchostenosis upon CT examination. CONCLUSION: Being alert to bronchial rupture after trauma in children is helpful for diagnosis. Chest CT with three-dimensional reconstruction techniques and fiberoptic bronchoscopy are the most valuable diagnostic methods. The patients can show excellent results if the operation for a continuous valgus anastomosis of the posterior wall and interrupted end-to-end valgus anastomosis of the anterior wall on the ruptured side is performed in the early stage of traumatic bronchial rupture.

Intrathoracic shoulder dislocation causing rupture of the right main bronchus.

An intrathoracic shoulder dislocation is a rare injury, usually the result of high-energy trauma [Hawkes et al. in Am J Orthop 43(4):E74-E78, 2014; Tsai et al. in Ann Thorac Cardiovasc Surg 20:592-594, 2014, in Rupprecht et al. Bull Emerg Trauma 5(3):212-214, 2017; Abellan et al. J Orthop Surg (Hong Kong)18(2):254-257, 2010]. It often occurs in conjunction with thoracic, pelvic, and long bone injuries. In addition, there is often significant injuries to the shoulder girdle and chest wall associated with neurovascular compromise [Abellan et al. J Orthop Surg (Hong Kong)18(2):254-257, 2010; Lin et al. JBJS Case Connect 6(1):e61, 2016]. Following a literature review, it appears that no cases have been reported of an intrathoracic shoulder dislocation associated with a rupture of the ipsilateral main bronchus. We present a case of a rupture of the right main bronchus that occurred due to high-energy impact and an associated intrathoracic right-shoulder fracture dislocation. Computed tomography identified diastasis of the ipsilateral first intercostal space, humeral head indentation in the hilum of the lung, and a pneumoarthrogram of the right glenohumeral joint.

[Transsternal occlusion of main bronchi fistulae after pneumonectomy]. / Transsternal'naya okklyuziya svishcha glavnogo bronkha posle pnevmonektomii.

OBJECTIVE: To summarize our experience in transsternal occlusion of main bronchus fistula. MATERIAL AND METHODS: We have performed 146 transsternal occlusions of the main bronchi for the period from 1979 to 2018. There were 123 (84.2%) men and 23 (15.7%) women. Mean age of patients was 63 years. Lung tuberculosis was diagnosed in 36 (24.7%) patients, lung cancer - 91 (62.3%) patients, non-specific suppurative lung diseases - 14 (9.6%) patients, trauma - 5 (3.4%) patients. All patients underwent transsternal occlusion of the main bronchi fistulae with or without pericardial cavity dissection. Wedge-shaped bronchial resection or tracheal bifurcation resection were carried out for a short stump fistula. RESULTS: Perioperative complications occurred in 28 (19.2%) out of 146 patients. Intraoperative complications developed in 4 (2.6%) patients. Postoperative complications were observed in 25 (17.1%) patients. Intraoperative mortality rate was 1.4% (n=2), postoperative mortality - 6.2% (n=9). Thus, overall mortality rate was 7.6% (n=11 It should be noted that intraoperative complications were absent if dissection of the pericardium and pulmonary artery stump ligation were not performed. CONCLUSION: Transsternal occlusion of the main bronchi fistulae was successful in 80.8% of patients. In these cases, healing of fistulae was not associated with any complications. Thus, we believe that transsternal occlusion of the main bronchial stump fistula should be considered as preferable surgical strategy.

Nix/BNIP3L-dependent mitophagy accounts for airway epithelial cell injury induced by cigarette smoke.

Cigarette smoke-induced airway epithelial cell mitophagy is an important mechanism in the pathogenesis of chronic obstructive pulmonary disease (COPD). Mitochondrial protein Nix (also known as BNIP3L) is a selective autophagy receptor and participates in several human diseases. However, little is known about the role of Nix in airway epithelial cell injury during the development of COPD. The aim of the present study is to investigate the effects of Nix on mitophagy and mitochondrial function in airway epithelial cells exposed to cigarette smoke extract (CSE). Our present study has found that CSE could increase Nix protein expression and induce mitophagy in airway epithelial cells. And Nix siRNA significantly inhibited mitophagy and attenuated mitochondrial dysfunction and cell injury when airway epithelial cells were stimulated with 7.5% CSE. In contrast, Nix overexpression enhanced mitophagy and aggravated mitochondrial dysfunction and cell injury when airway epithelial cells were incubated with 7.5% CSE. These data suggest that Nix-dependent mitophagy promotes airway epithelial cell and mitochondria injury induced by cigarette smoke, and may be involved in the pathogenesis of COPD and other cigarette smoke-associated diseases.

Analysis of Related Factors for the Retention Time of Tracheobronchial Foreign Bodies in Pediatrics.

BACKGROUND: This study aims to investigate the related factors for the retention time of tracheobronchial foreign bodies in infants and children, to provide help for the assessment of the disease, surgical risk, and prognosis. MATERIALS AND METHODS: The clinical data of 1060 patients with tracheobronchial foreign bodies from January 2015 to December 2015 were retrospectively studied, and the correlation of the retention time of foreign bodies with age, gender, preoperative complications, granulation formation, operation time, and hospital stay was analyzed. RESULTS: The retention time of foreign bodies was not correlated with age (r = 0.041, P = 0.194) and gender (r = 0.039, P = 0.214) but was correlated with preoperative complications (r = 0.072, P = 0.023), granulation formation (r = 0.134, P < 0.001), operation time (r = 0.112, P < 0.001), and hospital stay (r = 0.189, P < 0.001). CONCLUSIONS: The retention time of foreign bodies was closely correlated with granulation formation, preoperative complications, operation time, and hospital stay.

miR-221 participates in the airway epithelial cells injury in asthma via targeting SIRT1.

AIM OF THE STUDY: To investigate the role of microRNA-221 (miR-221) in the airway epithelial cell injury in asthma and delineate the underlying mechanism that may involve with SIRT1. MATERIALS AND METHOD: Bronchial epithelial cells from asthma patients and healthy controls were obtained by bronchoscopic brushing. The miR-221 and SIRT1 mRNA level in collected cells were detected by qRT-CPR. BEAS2B cell lines were cultured in vitro. In order to up-regulate miR-221 and SIRT1, miR-221 mimic and pcDNA3.1-SIRT1 vector was transfected into BEAS2B cells, respectively. The expression changes of miR-221 and SIRT1 after transfection was observed by qRT-PCR and Western blot. The target relationship between miR-221 and SIRT1 was confirmed using dual-luciferase reporter assay.The cell viability changes after transfection was measured using cellTiter-blue reagent. The apoptosis rate was detected by flow cytometry. RESULT: Compared with healthy controls, miR-221 expression significantly increased in bronchial epithelial cells from patients subjects. In contrast, the level of SIRT1 mRNA reduced in the bronchial epithelial cell from asthma patients. In vitro, up-regulation of miR-221 could inhibit the expression of SIRT1 both at mRNA and protein level in BEAS2B cells. A negative correlation between miR-221 and SIRT1 mRNA in samples from patients was confirmed and dual-luciferase reporter assay showed that miR-221 directly binds to the 3'UTR of SIRT1 mRNA. Overexpression of miR-221 or SIRT1 knockdown could inhibit proliferation but induce apoptosis in BEAS2B cells. Moreover, up-regulation of SIRT1 could antagonize miR-221's inhibitory effect. CONCLUSION: miR-221 may participate in the airway epithelial cells injury in asthma via targeting SIRT1.

Tube tip and cuff position using different strategies for placement of currently available paediatric tracheal tubes.

BACKGROUND: Tracheal tube tip and cuff positions of different cuffed paediatric tracheal tube brands in the trachea can vary with design. METHODS: Data from three clinical studies with measured tracheal lengths were pooled in a database including 422 children aged from birth to 16 yr. Dimensional data of seven cuffed paediatric tracheal tube brands (ID 3.0-7.0 mm) were recorded. Positions of tracheal tube tip and upper cuff border were calculated for each of the 422 tracheas using depth mark based tracheal tube placement, placement of the tracheal tube tip at a calculated safety distance above the carina, and mid-tracheal tube placement. Percentage of accidental bronchial intubations and tracheal tube cuff positions in the subglottic or supraglottic region were calculated. RESULTS: Depth mark based tracheal tube placement resulted in accidental bronchial intubation of up to 18% of cases and tracheal tube cuffs being placed in the subglottic region in up to 91%. Tracheal tube tip placement at a calculated safety distance resulted in up to 54% of tube cuffs placed too high. Mid-tracheal tube placement led to 100% subglottic or supraglottic tracheal tube cuff positions. CONCLUSIONS: All studied cuffed paediatric tracheal tubes have major design flaws potentially leading to airway complications. Tracheal tube manufacturers are urgently asked to improve the design of cuffed paediatric tracheal tubes. Alternative strategies for tracheal tube placement can allow safe tracheal tube placement of uncuffed but not of cuffed tracheal tubes.

Toll-Like Receptor Agonists Modulate Wound Regeneration in Airway Epithelial Cells.

BACKGROUND: Impaired regeneration of airway epithelium may lead to persistence of inflammation and remodelling. Regeneration of injured epithelium is a complex phenomenon and the role of toll-like receptors (TLRs) in the stimulation of respiratory virus products in this process has not been established. OBJECTIVE: This study was undertaken to test the hypothesis that the wound repair process in airway epithelium is modulated by microbial products via toll-like receptors. METHODS: Injured and not-injured bronchial epithelial cells (ECs) (BEAS-2B line) were incubated with the TLR agonists poly(I:C), lipopolisacharide (LPS), allergen Der p1, and supernatants from virus-infected epithelial cells, either alone or in combination with TLR inhibitors. Regeneration and immune response in injured and not-injured cells were studied. RESULTS: Addition of either poly(I:C) or LPS to ECs induced a marked inhibition of wound repair. Supernatants from RV1b-infected cells also decreased regeneration. Preincubation of injured and not-injured ECs with TLR inhibitors decreased LPS and poly(I:C)-induced repair inhibition. TGF-ß and RANTES mRNA expression was higher in injured ECs and IFN-α, IFN-ß, IL-8, and VEGF mRNA expression was lower in damaged epithelium as compared to not-injured. Stimulation with poly(I:C) increased IFN-α and IFN-ß mRNA expression in injured cells, and LPS stimulation decreased interferons mRNA expression both in not-injured and injured ECs. CONCLUSION: Regeneration of the airway epithelium is modulated by microbial products via toll-like receptors.