Prevalence of airway patency and air pocket in critically buried avalanche victims - a scoping review.

INTRODUCTION: Survival of critically buried avalanche victims is directly dependent on the patency of the airway and the victims' ability to breathe. While guidelines and avalanche research have consistently emphasized on the importance of airway patency, there is a notable lack of evidence regarding its prevalence. OBJECTIVE: The aim of this review is to provide insight into the prevalence of airway patency and air pocket in critically buried avalanche victims. METHODS: A scoping review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline extension for scoping reviews. MEDLINE and Cochrane databases, as well as additional manual searching was performed to identify literature reporting data on airway patency and the presence of an air pocket in critically buried avalanche victims. After eliminating duplicates, we screened abstracts and main texts to identify eligible studies. RESULTS: Of 4,109 studies identified 154 were eligible for further screening. Twenty-four publications and three additional data sources with a total number of 566 cases were included in this review. The proportion of short-term (< 35 min) to long-term burial (≥ 35 min) in the analysed studies was 19% and 66%, respectively. The burial duration remained unknown in 12% of cases. The prevalence of airway patency in critically buried avalanche victims was 41% while that of airway obstruction was 12%, with an overall rate of reporting as low as 50%. An air pocket was present in 19% of cases, absent in 46% and unknown in 35% of the cases. CONCLUSION: The present study found that in critically buried avalanche victims patent airways were more than three times more prevalent than obstructed, with the airway status reported only in half of the cases. This high rate of airway patency supports the ongoing development and the effectiveness of avalanche rescue systems which oppose asphyxiation in critically buried avalanche victims. Further effort should be done to improve the documentation of airway patency and the presence of an air pocket in avalanche victims and to identify factors affecting the rate of airway obstruction.

A New Distal Pharyngeal Airway Device Associated with a Reduced Need for Chin-Lift and Jaw-Thrust Maneuvers in Sedated Patients.

Oropharyngeal airways (OPA) or nasopharyngeal airways (NPA) sometimes require chin-lift or jaw-thrust (CLJT) maneuvers to relieve airway obstruction which creates the burden of continuous hands-on care by the anesthesia provider. A new distal pharyngeal airway device (DPA) was used on 63 successive ambulatory surgery patients to assess the frequency of patients requiring manual CLJT maneuvers to prevent airway obstruction. Results were then compared with a contemporaneous group of patients who had used OPA or NPA devices for similar procedures. Patients using the DPA had a 38.5% lower rate of CLJT maneuvers compared with the combined OPA/NPA groups (22.2% of 63 vs. 60.7% of 163, P ≤ .001). Moreover, the results for the DPA group were close to those of the natural airway group (22.2% of 62 vs. 24.8% of 233, P = .66) Results were similar for a sub-set of the above groups who required deep sedation or deep extubation. CLJT maneuvers were common in this ambulatory surgery setting. The new DPA device was associated with a reduced need for such manual maneuvers when compared with similar patients who received OPA or NPA devices and is comparable with the rate for natural airways.

Treatment of malignant airway obstruction with Y-shape sigma stent loaded with I125 seeds installed via rigid bronchoscopy.

PURPOSE: To summarize and analyze the safety and efficacy of a Y-shape Sigma stent loaded with I125 in patients with inoperable malignant main airway obstruction. METHODS: This study was approved by the Institutional Ethics Committee, and a written informed consent was obtained from each participant. A Y-shape Sigma stent loaded with I125 was placed under vision from rigid bronchoscopy. The primary endpoint was alleviation of symptoms and improvement of Karnofsky Performance Status (KPS) score, and the secondary endpoint was complications and technical success. RESULTS: From November 2018 through June 2023, total 33 patients with malignant airway obstruction were palliatively treated by installing Y-shape Sigma stents loaded with I125. The airway lumen was immediately restored and the average airway opening significantly increased to 70 ± 9.4% after the procedure from baseline 30.2 ± 10.5% (p < 0.05). Average KPS score was improved from baseline 30.0 ± 10.0 to 70.0 ± 10.0 (p < 0.05) as well as PaO2 from baseline 50.1 ± 15.4 mmHg to 89.3 ± 8.6 mmHg (p < 0.05). The technical success rate of placing the stent in this study was 73%, and adverse events or complications including bleeding, I125 loss, and airway infection occurred during or after the procedure. CONCLUSION: Placement of Y-shape Sigma stents under vision from rigid bronchoscopy in the patients with malignant airway obstruction is feasible and it immediately alleviates dyspnea and significantly improves quality of life.

Benign multinodular goitre presenting as acute decompensated type two respiratory failure.

Acute airway obstruction is a life-threatening complication of benign goitre mostly occurring in cases of known progressing goitres. The index presentation of goitre with decompensated type two respiratory failure is an exceedingly rare and a diagnostically challenging presentation. We discuss the case of a woman in her 50 s, who had been diagnosed with asthma by her general practitioner, but during admission was found to have a large goitre with retrosternal extension causing critical tracheal compression. She presented with acute decompensated type two respiratory failure. We explore the diagnostic confounding posed by the patient's background of asthma and describe the initial management of the patient with non-invasive ventilation by the emergency department. The diagnosis of upper airway obstruction was not apparent which is an interesting anomaly in this case. She underwent an emergency hemithyroidectomy and recovered with a resolution of her respiratory symptoms. Histology confirmed benign multinodular hyperplasia.

Airway obstruction in two children with congenital central hypoventilation syndrome and review of the literature.

Congenital central hypoventilation syndrome (CCHS) is an autosomal dominant disease that is caused by heterozygous mutations in the paired-like homeobox 2B gene (PHOX2B). Madani et al. described an abnormally high degree of not only central apnea but also obstructive and mixed apnea in Phox2b27Ala/+newborn mice. Newborns with CCHS must undergo polysomnography for obstructive respiratory events in order to guide the optimal ventilation strategy if oxygen desaturation, bradycardia, and malaise persist under noninvasive ventilation. Newborns and infants with CCHS must be systematically tested for obstructive apnea, especially in cases of inefficient noninvasive ventilation.

Endobronchial silicone spigot in prolonged air leaks: Nationwide study on outcomes and risk factors for treatment failure.

BACKGROUND: The endobronchial silicone spigot, also known as the endobronchial Watanabe spigot, is used in bronchoscopic interventions to manage prolonged pulmonary air leakage. However, the outcomes of this procedure have not been thoroughly investigated. METHODS: Using a Japanese national inpatient database from April 2014 to March 2022, we assessed the clinical characteristics and outcomes of all eligible patients who received the endobronchial spigot. We also investigated risk factors associated with treatment failure. Treatment failure was defined as in-hospital death or the need for surgery after bronchial occlusion. RESULTS: We analyzed data of 1095 patients who underwent bronchial occlusion using the endobronchial spigot. Among them, 252 patients (23.0%) died during hospitalization, and 403 patients (36.8%) experienced treatment failure. Factors associated with treatment failure included age between 85 and 94 years (odds ratio [OR] 1.83; 95% confidence intervals [CI], 1.04-3.21); male sex (OR 2.43; 95% CI, 1.44-4.11); low Barthel index score; comorbidities of interstitial pneumonia (OR 1.71; 95% CI, 1.18-2.48); antibiotics treatment (OR 1.45; 95% CI, 1.02-2.07); steroids treatment (OR 1.59; 95% CI, 1.07-2.36); and surgery prior to bronchial occlusion (OR 2.08; 95% CI, 1.29-3.35). In contrast, pleurodesis after bronchial occlusion (OR 0.49; 95% CI, 0.32-0.75), and admission to high-volume hospitals were inversely associated with treatment failure (OR 0.58; 95% CI, 0.37-0.90). CONCLUSIONS: The endobronchial Watanabe spigot could be a nonsurgical treatment option for patients with prolonged pulmonary air leaks. Our findings will help identify patients who may benefit from such bronchial interventions.

Minimally-invasive airway management and early cleft palate repair in infants born with Robin sequence.

The objective of this study was to report outcomes of early cleft palate repair in infants born with Robin sequence (RS). A retrospective case series in a tertiary referral paediatric hospital was carried out, examining a consecutive series of 69 infants born with RS and cleft palate. A minimally invasive approach was taken to upper airway obstruction, with liberal nasopharyngeal airway (NPA) and non-invasive ventilation (NIV) use, guided by sleep studies. The palate was repaired between 6 and 9 months with a modified Malek technique. The most frequently used airway adjunct (59.4% of patients) was an NPA and the median duration of use was 5.6 months. All patients underwent a modified Malek cleft palate repair at a median of 7 months of age. Overnight oximetry demonstrated higher mean oxygen saturation (SpO2) across the group from initial neonatal admission to discharge (median 96.5% (interquartile range [IQR] 95-98%) vs 97.45% (IQR 96.5-98%) (P = 0.2, N = 34). Of those with a cardiorespiratory polysomnogram, the obstructive apnoea-hypopnea index (OAHI) was significantly lower postoperatively (5.9 vs 2.8, P = 0.028). This study supports the use of non-surgical airway strategies and early cleft palate repair in infants born with RS and cleft palate.

Airway stenting for liberation from positive pressure ventilation in patients with central airway obstruction presenting with acute respiratory failure.

BACKGROUND: Central airway obstruction (CAO) can lead to acute respiratory failure (RF) necessitating positive pressure ventilation (PPV). The efficacy of airway stenting to aid liberation from PPV in patients with severe acute RF has been scarcely published. We present a systematic review and our recent experience. METHODS: A systematic review of PubMed was performed, and a retrospective review of cases performed at our two institutions from 2018 to 2022 in adult patients who needed stent insertion for extrinsic or mixed CAO complicated by RF necessitating PPV. RESULTS: Fifteen studies were identified with a total of 156 patients. The weighted mean of successful liberation from PPV post-stenting was 84.5% and the median survival was 127.9 days. Our retrospective series included a total of 24 patients. The most common etiology was malignant CAO (83%). The types of PPV used included high-flow nasal cannula (HFNC) (21%), non-invasive ventilation (NIV) (17%) and Invasive Mechanical Ventilation (62%). The overall rate of successful liberation from PPV was 79%, with 55% of HFNC and NIV cases being liberated immediately post-procedure. The median survival of the patients with MCAO that were successfully liberated from PPV was 74 days (n = 16, range 3-893 days), and for those with that failed to be liberated from PPV, it was 22 days (n = 4, range 9-26 days). CONCLUSION: In patients presenting with acute RF from extrinsic or mixed morphology CAO requiring PPV, airway stenting can successfully liberate most from the PPV. This may allow patients to receive pathology-directed treatment and better end-of-life care.

Effective Differences between 2D and 3D Planned Brachytherapy in Lung Cancer: An Institutional Retrospective Study.

Background and Objectives: Advanced lung cancer is usually manifested by endoluminal tumor propagation, resulting in central airway obstruction. The objective of this study is to compare the high dose rate brachytherapy treatment outcomes in non-small-cell lung cancer (NSCLC) depending on the treatment planning pattern-two-dimension (2D) or three-dimension (3D) treatment planning. Materials and Methods: The study was retrospective and two groups of patients were compared in it (a group of 101 patients who underwent 2D planned high-dose-rate endobronchial brachytherapy (HDR-EBBT) in 2017/18 and a group of 83 patients who underwent 3D planned HDR-EBBT between January 2021 and June 2023). Results: In the group of 3D planned brachytherapy patients, there was a significant improvement in terms of loss of symptoms of bronchial obstruction (p = 0.038), but no improvement in terms of ECOG PS (European Cooperative Oncology Group Performance Status) of the patient (p = 0.847) and loss of lung atelectasis (if there was any at the beginning of the disease) (p = 0.781). Two-year overall survival and time-to-progression periods were similar for both groups of patients (p = 0.110 and 0.154). Fewer treatment complications were observed, and 91.4% were in 3D planned brachytherapy (BT) patients. Conclusions: Three-dimensionally planned HDR-EBBT is a suggestive, effective palliative method for the disobstruction of large airways caused by endobronchial lung tumor growth. Independent or more often combined with other types of specific oncological treatment, it certainly leads to the loss of symptoms caused by bronchial obstruction and the improvement of the quality of life of patients with advanced NSCLC. Complications of the procedure with 3D planning are less compared to 2D planned HDR-EBBT.

Aryepiglottic Cyst Developed Hours After Tracheal Intubation Causing Acute Upper Airway Ball-Valve Obstruction: A Case Report.

This is the first case report describing an aryepiglottic cyst resulting in critical airway compromise after an uneventful tracheal intubation. We present the case of a 55-year-old woman who developed acute dyspnea and stridor several hours after the surgery. She was found to have significant upper airway obstruction owing to a large left aryepiglottic cyst with a ball-valve effect.

Airway necrosis and granulation tissue formation caused by Rhizopus oryzae leading to severe upper airway obstruction: a case report.

Pulmonary Mucormycosis is a fatal infectious disease with high mortality rate. The occurrence of Mucormycosis is commonly related to the fungal virulence and the host's immunological defenses against pathogens. Mucormycosis infection and granulation tissue formation occurred in the upper airway was rarely reported. This patient was a 60-year-old male with diabetes mellitus, who was admitted to hospital due to progressive cough, sputum and dyspnea. High-resolution computed tomography (HRCT) and bronchoscopy revealed extensive tracheal mucosal necrosis, granulation tissue proliferation, and severe airway stenosis. The mucosal necrotic tissue was induced by the infection of Rhizopus Oryzae, confirmed by metagenomic next-generation sequencing (mNGS) in tissue biopsy. This patient was treated with the placement of a covered stent and local instillation of amphotericin B via bronchoscope. The tracheal mucosal necrosis was markedly alleviated, the symptoms of cough, shortness of breath, as well as exercise tolerance were significantly improved. The placement of airway stent and transbronchial microtube drip of amphotericin B could conduce to rapidly relieve the severe airway obstruction due to Mucormycosis infection.

Negative pressure pulmonary edema after laparoscopic cholecystectomy: A case report and literature review.

RATIONALE: Negative pressure pulmonary edema (NPPE) is an acute onset of non-cardiogenic interstitial pulmonary edema, commonly seen among surgical patients after extubation from general aneasthesia. It is mainly caused by rapid inspiration with acute upper airway obstruction resulting in significant negative thoracic pressure. PATIENT CONCERNS: A 24-year-old female patient who underwent laparoscopic cholecystectomy under general anesthesia and developed NPPE postoperatively. DIAGNOSES: Her main clinical manifestation was coughing up pink foamy sputum; postoperative CT showed increased texture in both lungs and bilateral ground glass opacities. INTERVENTIONS: Diuretics and steroids were used, and symptomatic supportive treatments such as oxygen were given. OUTCOMES: After treatment, on the fourth post-operative day, her symptoms were relieved and her vital signs were stable enough for her to be discharged. LESSONS: Although this is a rare and severe complication, the prognosis of NPPE is good when it is managed with proper diagnosis and treatment.

Early respiratory interventional therapy combined with antifungal agent for endobronchial cryptococcosis: A case report and literature review.

RATIONALE: Cryptococcosis presenting as endobronchial obstruction and lung collapse is an extremely rare occurrence. While these patients were treated with antifungal agents, unfortunately, half of them showed a suboptimal response. PATIENT CONCERNS: A 45-year-old immunocompetent male was admitted to the hospital due to a cough, yellow phlegm, and dyspnea persisting for 5 months. Chest computer tomography revealed a mass in the right main bronchus accompanied by right lower lobe atelectasis. DIAGNOSES: Endobronchial cryptococcosis presenting as endobronchial obstruction and lung collapse. INTERVENTIONS: Early rigid bronchoscopic therapy was performed to resect endobronchial obstruction, which combined with antifungal agent. OUTCOMES: The patient recovered well with completely clinical and radiologic resolution at 1 year follow-up. LESSONS: This case provides a good example of successful utilization of the early respiratory interventional therapy combined with antifungal agent in obstructive endobronchial cryptococcosis.

Association between heated tobacco product use and airway obstruction: a single-centre observational study, Japan.

BACKGROUND: While heated tobacco products (HTPs) may affect pulmonary function, the evidence supporting the utility of screening for HTP use in clinical settings is insufficient. We examined the association between HTP use and airway obstruction after switching from cigarettes. METHOD: The study subjects were patients aged ≥20 years undergoing surgery from December 2021 to September 2022 who completed spirometry and reported tobacco (cigarette and HTP) use status during the preoperative assessment. Airway obstruction was defined as forced expiratory volume in 1 s to forced vital capacity ratio below the lower limit of normal. Current tobacco use was defined as past-30-day use. Multivariable Poisson regression analysis was performed to examine the associations between HTP use and airway obstruction by adjusting for demographic characteristics, lifetime cigarette smoking (pack-year) and duration of smoking cessation. RESULTS: Overall (N=2850, 55.4% women, mean age 62.4), 4.6% and 10.7% reported current HTP use and cigarette smoking, respectively. 16.8% had airway obstruction. Airway obstruction was more common among current HTP-only users (adjusted prevalence ratio (APR)=2.32), current cigarette-only smokers (APR=2.57) and current dual users (APR=2.82) than never-tobacco users. Among current tobacco users (N=398), the prevalence of airway obstruction was not significantly different between HTP-only users and cigarette-only smokers. Among former cigarette smokers (>30-day cigarette quitters) (N=1077), current HTP users had 1.42 times the increased prevalence of airway obstruction than never-HTP users after adjusting for cigarette pack-year; a stronger association was observed when the analysis was restricted to ≥5-year cigarette quitters (N=772) (APR=1.96, vs never HTP users). CONCLUSION: Current HTP use was associated with airway obstruction among patients with cancer who had completely switched from cigarettes even after quitting smoking for a long period. Patients should be routinely screened for HTP use and advised to quit any tobacco.

miR-34c-5p inhibited fibroblast proliferation, differentiation and epithelial-mesenchymal transition in benign airway stenosis via MDMX/p53 pathway.

Benign airway stenosis (BAS) means airway stenosis or obstruction that results from a variety of non-malignant factors, including tuberculosis, trauma, benign tumors, etc. In consideration of the currently limited research on microRNAs in BAS, this study aimed to explore the role and mechanism of miR-34c-5p in BAS. The expression of miR-34c-5p in BAS granulation tissues showed a significant down-regulation compared with the normal control group. Moreover, miR-34c-5p mimics suppressed the proliferation and differentiation of human bronchial fibroblasts (HBFs) and the epithelial-mesenchymal transition (EMT) of human bronchial epithelial cells (HBE). Conversely, miR-34c-5p inhibitors aggravated those effects. A dual-luciferase reporter assay confirmed that miR-34c-5p can target MDMX rather than Notch1. The over-expression of MDMX can reverse the inhibiting effect of miR-34c-5p on HBFs proliferation, differentiation and EMT. Furthermore, the expressions of tumor protein (p53) and PTEN were down-regulated following the over-expression of MDMX. In addition, the expressions of PI3K and AKT showed an up-regulation. In conclusion, miR-34c-5p was down-regulated in BAS and may inhibit fibroblast proliferation differentiation and EMT in BAS via the MDMX/p53 signaling axis. These findings expand the understanding of the role of miR-34c-5p and will help develop new treatment strategies for BAS.

Long-range optical coherence tomography of pediatric airway during drug induced sleep endoscopy: A preliminary report.

OBJECTIVE: Drug induced sleep endoscopy (DISE) is often performed for pediatric obstructive sleep apnea (OSA) when initial diagnostic studies do not provide adequate information for therapy. However, DISE scoring is subjective and with limitations. This proof-of-concept study demonstrates the use of a novel long-range optical coherence tomography (LR-OCT) system during DISE of two pediatric patients. METHODS: LR-OCT was used to visualize the airway of pediatric patients during DISE. At the conclusion of DISE, the OCT probe was guided in the airway under endoscopic visual guidance, and cross-sectional images were acquired at the four VOTE locations. Data processing involved image resizing and alignment, followed by rendering of three-dimensional (3D) volumetric models of the airways. RESULTS: Two patients were included in this study. Patient one had 18.4%, 20.9%, 72.3%, and 97.3% maximal obstruction at velum, oropharynx, tongue base, and epiglottis, while patient two had 40.2%, 41.4%, 8.0%, and 17.5% maximal obstruction at these regions, respectively. Three-dimensional reconstructions of patients' airways were also constructed from the OCT images. CONCLUSION: This proof-of-concept study demonstrates the successful evaluation of pediatric airway during DISE using LR-OCT, which accurately identified sites and degrees of obstruction with respective 3D airway reconstruction.

Ventilatory capacity in CLAD is driven by dysfunctional airway structure.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) encompasses three main phenotypes: bronchiolitis obliterans syndrome (BOS), restrictive allograft syndrome (RAS) and a Mixed phenotype combining both pathologies. How the airway structure in its entirety is affected in these phenotypes is still poorly understood. METHODS: A detailed analysis of airway morphometry was applied to gain insights on the effects of airway remodelling on the distribution of alveolar ventilation in end-stage CLAD. Ex vivo whole lung µCT and tissue-core µCT scanning of six control, six BOS, three RAS and three Mixed explant lung grafts (9 male, 9 female, 2014-2021, Leuven, Belgium) were used for digital airway reconstruction and calculation of airway dimensions in relation to luminal obstructions. FINDINGS: BOS and Mixed explants demonstrated airway obstructions of proximal bronchioles (starting at generation five), while RAS explants particularly had airway obstructions in the most distal bronchioles (generation >12). In BOS and Mixed explants 76% and 84% of bronchioles were obstructed, respectively, while this was 22% in RAS. Bronchiolar obstructions were mainly caused by lymphocytic inflammation of the airway wall or fibrotic remodelling, i.e. constrictive bronchiolitis. Proximal bronchiolectasis and imbalance in distal lung ventilation were present in all CLAD phenotypes and explain poor lung function and deterioration of specific lung function parameters. INTERPRETATION: Alterations in the structure of conducting bronchioles revealed CLAD to affect alveolar ventilatory distribution in a regional fashion. The significance of various obstructions, particularly those associated with mucus, is highlighted. FUNDING: This research was funded with the National research fund Flanders (G060322N), received by R.V.

How should one intervene when a foreign body is blocking a child's oral cavity?

BACKGROUND: Foreign bodies lodged in the oral cavity can be life-threatening. Their removal should be determined on the basis of the patient's condition, the type of object, the removal techniques available, the appropriate medication available and the potential complications. CASE REPORT: A 9-month-old girl was brought to the emergency room by ambulance after a part of a toy became stuck in her oral cavity. Her father had unsuccessfully attempted to remove it at home. A blue cylindrical, rigid plastic toy part was seen during examination of her oral cavity and her tongue was trapped inside it. On initial assessment, her vital signs were within the normal range. She was agitated, a small amount of saliva mixed with blood was coming out of her mouth and she could not swallow her spittle. She was treated in the resuscitation room by an otorhinolaryngologist and a paediatric emergency team, and the foreign body was removed using bayonet forceps inside the mouth. The child was monitored in the paediatric emergency observation unit for 6 hours for signs of asphyxia and aspiration, and she was discharged without complications. CONCLUSION: Foreign bodies in the oral cavity can cause serious complications, including injury, bleeding and sudden airway obstruction. Experienced healthcare professionals, especially those skilled in airway management, should handle these cases using a multidisciplinary approach to ensure respiratory safety.Abbreviations: LMA: laryngeal mask airway; PED: paediatric emergency department.