Tracheomalacia is a condition where the tracheal wall is abnormally soft and prone to collapse during increased respiratory efforts. Airway malacia can manifest as segmental conditions like laryngomalacia, tracheomalacia and bronchomalacia, or as diffuse conditions such as tracheobronchomalacia (TBM). Unlike long-segment congenital tracheal stenosis, where surgery may be the preferred treatment, the management of long-segment TBM remains controversial.

UNASSIGNED: This present study evaluated the effect of combination therapy with stromal cell-derived factor 1α (SDF-1α) and high-mobility group box 1 (HMGB1) peptide on the regeneration of tracheal injury in a rat model.
UNASSIGNED: To improve this effect, SDF-1α was incorporated into a gelatin hydrogel, which was then applied to the damaged tracheal cartilage of rats for local release. Furthermore, HMGB1 peptide was repeatedly administered intravenously. Regeneration of damaged tracheal cartilage was evaluated in terms of cell recruitment.
UNASSIGNED: Mesenchymal stem cells (MSC) with C-X-C motif chemokine receptor 4 (CXCR4) were mobilized more into the injured area, and consequently the fastest tracheal cartilage regeneration was observed in the combination therapy group eight weeks after injury.
UNASSIGNED: The present study demonstrated that combination therapy with gelatin hydrogel incorporating SDF-1α and HMGB1 peptide injected intravenously can enhance the recruitment of CXCR4-positive MSC, promoting the regeneration of damaged tracheal cartilage.

In tracheobronchomalacia, the structural weakening of the airway results in altered ventilatory mechanics. This case report describes a patient with known tracheobronchomalacia who experienced expiratory central airway collapse and dynamic pulmonary hyperinflation during peroral endoscopic myotomy (POEM) to treat symptomatic achalasia. We discuss the physiological considerations and potential complications of a POEM procedure with superimposed tracheobronchomalacia and present perioperative strategies for the prevention and management of this potentially deleterious combination. Although tracheobronchomalacia was a known condition in our patient, it is likely an underdiagnosed condition that may first present intraoperatively.

Introduction: Lower airway malacia (LAM) is characterized by a reduction in the cross-sectional luminal area during quiet respiration. There is no gold standard diagnostic test; however, flexible fiberoptic bronchoscopy (FFB) is most frequently utilized. The exact prevalence and incidence of LAM are unknown. This study aimed to determine the prevalence rates of pediatric patients diagnosed with LAM, offer a detailed understanding of their demographic and clinical characteristics, and investigate distinctions between two specific types of LAM, namely, tracheomalacia (TM) and bronchomalacia (BM). Materials and Methods: Patients younger than 18 years diagnosed with LAM using FFB were included in this retrospective case series. Demographic and clinical characteristics and comorbid disorders were compared between patients with isolated BM and those with isolated TM or tracheobronchomalacia (TM/TBM). Results: Among 390 patients who underwent FFB, 65 (16.6%) were diagnosed with LAM, 16 (24.6%) with TM, and 56 (86.2%) with BM. The median age at diagnosis was 15 months. Among them, 59 (90.8%) had other comorbidities; gastrointestinal (GI) disorders were the most common (38.5%). The most common indications for bronchoscopy were recurrent/prolonged lower respiratory tract infections (LRTI) or wheezing (43.1%), while the most frequently observed respiratory physical examination finding was stridor (35.4%). Patients with TM/TBM had significantly higher frequencies of premature births, stridor, retraction, and GI disorders. Conclusion: Patients with stridor without typical laryngomalacia features or recurrent or prolonged LRTI should undergo prompt evaluation for LAM. The potential coexistence of GI disorders such as gastroesophageal reflux disease and swallowing dysfunction should also be considered.

Large airway disorders encompass a large variety of diseases and pathology, with broad categories including anatomic variants, congenital abnormalities, acquired abnormalities, inflammatory/infiltrative causes, infection, and tumors. The most common diseases in each category are discussed with a focus on the salient imaging findings. Pitfalls to beware of are discussed through the article, and concludes with a general method to approaching large airways pathology that should provide the reader with a basic framework and understanding of this complex topic.

We report the case of a 53-year-old female who developed tracheobronchomalacia immediately following an uncomplicated robotic hysterectomy with bilateral salpingo-oophorectomy to treat postmenopausal bleeding. Induction of anesthesia was notable for moderately difficult intubation, managed with applied cricothyroid pressure and a small 6.5 endotracheal tube placement via GlideScope. The surgical course was uneventful. The patient remained intubated in the post-anesthesia care unit but was not providing end-tidal volumes. Attempts to replace the endotracheal tube with a larger tube were unsuccessful and the patient was temporarily unable to ventilate. Rapid troubleshooting discovered that a laryngeal mask airway (LMA) could sufficiently ventilate the patient. An otolaryngologist was able to perform direct bronchoscopy, which revealed more than 50% dynamic anterior-posterior collapse of the trachea and bronchi. The patient was subsequently awakened from anesthesia and monitored in the intensive care unit, ventilating with an LMA. After a couple of hours, it was determined that the patient\'s airway was protected, and the LMA was removed.

Tracheobronchomalacia (TBM) occurs due to the weakening of cartilaginous part of the trachea, resulting in compromised airway function and leading to symptoms such as dyspnea, cough, and inability to clear secretions. Bronchiolitis obliterans syndrome (BOS) is the most prevalent late noninfectious pulmonary complication in patients who underwent allogeneic haematopoietic stem cell transplantation (HSCT). Therefore, patients experiencing progressive dyspnea and chronic cough after allogenic HSCT, with new obstructive pattern on pulmonary function test, are typically diagnosed with post-transplant BOS. However, it is important to note that TBM can also manifest as an obstructive defect pattern on pulmonary function test. Tracheomalacia has been reported as a rare complication of allogenic stem cell transplantation. We present two patients who developed TBM following allogeneic HSCT and were initially treated for post-transplant BOS but did not experience symptom improvement. However, after treatment with continuous positive airway pressure, their symptom subsided.

BACKGROUND: Tracheobronchomalacia (TBM) is characterized by excessive dynamic airway collapse. Severe TBM can be associated with substantial morbidity. Children with secondary TBM associated with esophageal atresia/tracheoesophageal fistula (EA/TEF) and vascular-related airway compression (VRAC) demonstrate clinical improvement following airway pexy surgery. It is unclear if children with severe primary TBM, without secondary etiologies (EA/TEF, vascular ring, intrinsic pulmonary pathology, or complex cardiac disease) demonstrate clinical improvement following airway pexy surgery.
METHODS: The study cohort consisted of 73 children with severe primary TBM who underwent airway pexy surgery between 2013 and 2020 at Boston Children\'s Hospital. Pre- and postoperative symptoms as well as bronchoscopic findings were compared with Fisher exact test for categorical data and Student\'s t-test for continuous data.
RESULTS: Statistically significant improvements in clinical symptoms were observed, including cough, noisy breathing, prolonged respiratory infections, pneumonias, exercise intolerance, cyanotic spells, brief resolved unexplained events (BRUE), and noninvasive positive pressure ventilation (NIPPV) dependence. No significant differences were seen regarding oxygen dependence, ventilator dependence, or respiratory distress requiring NIPPV. Comparison of pre- and postoperative dynamic bronchoscopy findings revealed statistically significant improvement in the percent of airway collapse in all anatomic locations except at the level of the upper trachea (usually not malacic). Despite some initial improvements, 21 (29%) patients remained symptomatic and underwent additional airway pexies with improvement in symptoms.
CONCLUSIONS: Airway pexy surgery resulted in significant improvement in clinical symptoms and bronchoscopic findings for children with severe primary TBM; however, future prospective and long-term studies are needed to confirm this benefit.

Acquired tracheobronchomalacia (ATBM) is a condition in which the tracheobronchial wall and cartilage progressively lose their rigidity, resulting in dynamic collapse during exhalation. In this report, we present a case of ATBM that developed following voice prosthesis implantation. To the best of our knowledge, this is the first documented case of such a condition in the medical English literature based on a PubMed search. A 63-year-old man was referred to National Kyushu Cancer Center in Japan with complaints of pharyngeal pain and a laryngeal tumor. The tumor was diagnosed as laryngeal cancer, and the patient underwent laryngectomy. Three months after the surgery, we implanted a voice prosthesis through a tracheoesophageal puncture. Two months after implantation, the patient experienced dyspnea. This condition was subsequently diagnosed as ATBM through computed tomography and bronchofiberscope examinations. After the removal of the voice prosthesis, there has been no progression of ATBM for over five years. While ATBM may not be a common occurrence in the practice of head and neck surgeons, it should be considered as a potential complication when patients report dyspnea following voice prosthesis implantation.

BACKGROUND: Tracheal collapse (TC), a common disease in dogs, is characterized by cough; however, little is known about the serum biomarkers that can objectively evaluate the severity of cough in canine TC. Furthermore, studies elucidating the relationship of fluoroscopic characteristics with the severity of cough are lacking. Therefore, this study aimed to evaluate the relationship between cough severity and clinical characteristics, fluoroscopic images, and new serum biomarkers in canine TC.
RESULTS: Fifty-one client-owned dogs diagnosed with TC based on fluoroscopic and clinical signs were enrolled in this study and divided into three groups according to the severity of cough (grade of cough: 0, 1, and 2). Signalments, comorbidities, and fluoroscopic characteristics were compared among the groups retrospectively. The serum matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), surfactant protein-A (SP-A), and syndecan-1 (SDC-1) levels were measured in all groups. No significant differences in age, breed, sex, or clinical history were observed among the groups. Concomitant pharyngeal collapse increased significantly with the severity of cough (p = .031). Based on the fluoroscopic characteristics, the TC grade of the carinal region increased significantly and consistently with the grade of cough (p = .03). The serum MMP-9 level was significantly higher in the grade 2 group than that in the grade 0 group (p = .014). The serum IL-6 level was significantly lower in the grade 1 group than that in the grade 0 group (p = .020). The serum SP-A and SDC-1 levels did not differ significantly among the groups.
CONCLUSIONS: The severity of cough with the progression of TC can be predicted with the fluoroscopic TC grade at the carinal region. MMP-9 may be used as an objective serum biomarker that represents cough severity to understand the pathogenesis.