Ferulic acid ameliorates lipopolysaccharide-induced tracheal injury via cGMP/PKGII signaling pathway

Background Tracheal injury is a common clinical condition that still lacks an effective therapy at present. Stimulation of epithelial sodium channel (ENaC) increases Na+ transport, which is a driving force to keep tracheal mucosa free edema fluid during tracheal injury. Ferulic acid (FA) has been proved to be effective in many respiratory diseases through exerting anti-oxidant, anti-inflammatory, and anti-thrombotic effects. However, these studies rarely involve the level of ion transport, especially ENaC. Methods C57BL/J male mice were treated intraperitoneally with normal saline or FA (100 mg/kg) 12 h before, and 12 h after intratracheal administration of lipopolysaccharide (LPS, 5 mg/kg), respectively. The effects of FA on tracheal injury were not only assessed through HE staining, immunofluorescence assay, and protein/mRNA expressions of ENaC located on tracheas, but also evaluated by the function of ENaC in mouse tracheal epithelial cells (MTECs). Besides, to explore the detailed mechanism about FA involved in LPS-induced tracheal injury, the content of cyclic guanosine monophosphate (cGMP) was measured, and Rp-cGMP (cGMP inhibitor) or cGMP-dependent protein kinase II (PKGII)-siRNA (siPKGII) were applied in primary MTECs, respectively. Results Histological examination results demonstrated that tracheal injury was obviously attenuated by pretreatment of FA. Meanwhile, FA could reverse LPS-induced reduction of both protein/mRNA expressions and ENaC activity. ELISA assay verified cGMP content was increased by FA, and administration of Rp-cGMP or transfection of siPKGII could reverse the FA up-regulated ENaC protein expression in MTECs. Conclusions Ferulic acid can attenuate LPS-induced tracheal injury through up-regulation of ENaC at least partially via the cGMP/PKGII pathway, which may provide a promising new direction for preventive and therapeutic strategy in tracheal injury.

Successful Treatment of Airway Rupture with Femoro-Femoral Venovenous Extracorporeal Membrane Oxygenation in Traumatic Tracheal Injury: A Case Report

BackgroundTraumatic tracheal injury is a rare type of trauma. In this type of injury, catastrophes may occur owing to a failure to secure the patient's airway. Extracorporeal membrane oxygenation (ECMO) is rescue therapy available for the treatment of urgent cardiorespiratory distress until the patient's vital signs have stabilized. The various applications of ECMO configurations have expanded the scope for this therapy.Case presentationWe describe the case of a 66-year-old man with tracheal rupture with thyroid cartilage fracture due to cultivator handle who was treated with veno-venous ECMO. This case reflects the role and limitations of veno-venous ECMO, in which patient survival was possible with a bi-femoral configuration while also ensuring a clear airway. ConclusionWe shared our experience with bi-femoral veno-venous ECMO as a therapeutic option to contribute to choosing an appropriate approach. Based on our review of the literature, the present case was an uncommon report of survival after tracheal rupture due to trauma without other complications.

Tracheal Repair with Human Umbilical Cord Mesenchymal Stem Cells Differentiated in Chondrocytes Grown on an Acellular Amniotic Membrane: A Pre-Clinical Approach

Acellular amniotic membrane (AM) has been studied, with promising results on the reconstruction of lesioned tissues, and has become an attractive approach for tracheal repair. This study aimed to evaluate the repair of the trachea with human umbilical cord mesenchymal stem cells (hucMSCs) differentiated in chondrocytes, grown on an experimental model. Tracheal defects were induced by surgical tracheostomy in 30 New Zealand rabbits, and the acellular amniotic membrane, with or without cells, was covering the defect. The hucMSCs were isolated and cultivated with chondrogenic differentiation over the culture of 14 days, and then grown on the AM. In this study, the AM was biocompatible and hucMSCs differentiated into chondrocytes. Our results demonstrated an important role for AM with cultured cells in the promotion of immature collagen, known to produce tissue regeneration. In addition, cartilaginous tissue was found at the tracheal defects, demonstrated by immunohistology results. This study suggests that this biomaterial implantation can be an effective future therapeutic alternative for patients with tracheal injury.

Acquired tracheoesophageal fistula in a pregnant patient with COVID-19 pneumonia on prolonged invasive ventilation

A previously healthy pregnant woman was diagnosed with COVID-19 pneumonia and was subsequently intubated. Throughout the course of her illness, the patient was treated for recurrent bouts of pneumonia. A high-resolution chest and neck CT scan confirmed the presence of a tracheoesophageal fistula (TEF), which may have been caused by the presence of the overinflated endotracheal cuff, prolonged steroid use, hypoxic injury and possible direct injury of the tracheal mucosa from COVID-19 itself. A temporising procedure, involving tracheostomy with an extended-length tracheal tube, was performed. Unfortunately, the patient succumbed to infection prior to definitive repair. This case highlights the importance of keeping a high index of suspicion for tracheal injury in patients who experience prolonged periods of intubation. It also underlies the high morbidity and mortality rate associated with TEF, although being a rare disease.

Conservative Treatment in Tracheobronchial Injuries—An Institutional Report

Tracheobronchial injuries are rare but potentially high-impact events with significant morbidity and mortality. Common etiologies include blunt or penetrating trauma, often combined with various complex injuries, while iatrogenic injury usually occurs during operation, intubation, or bronchoscopy. An early and accurate diagnosis and a multidisciplinary approach in a center experienced in treating airway lesions are essential to obtain favorable results. For a long time, surgery has been considered the treatment of choice for post-traumatic airway lesions. However, recent reports have shown a paradigm shift in the management of tracheal injury towards a conservative approach, especially in treating iatrogenic lesions. In our experience of 11 consecutive patients, although there are still definitive indications for surgery, we demonstrated the effectiveness of conservative treatment in patients with mixed varieties of tracheal injury by etiology, extension, and complications.

Experience of Emergency Cervical Tracheal Repair after Non-Iatrogenic Injury

Background: Non-iatrogenic cervical tracheal injury is very rare and challenging for emergency critical care, early diagnosis, and immediate repair. So, emergency repair after early definitive diagnosis is the mainstay to avoid mortality and morbidity. Methods: A retrospective, observational, cohort study is undertaken with collected data on 50 patients with emergency cervical tracheal repair after non-iatrogenic injury between January 2011 to January 2020 at our accident and emergency department in Minia and South Valley Universities. Results: The non-iatrogenic injury of the cervical trachea is more common in adult males (98%), and blunt trauma (70%) is the predominant type of injury. Subcutaneous emphysema (SE) is the most common presentation (99%). There are associated comorbidities like vascular (4%), maxillofacial (6%), head injury (2%), and esophageal tear (8%). Successful intubation is lifesaving, and early diagnosis and repair avoid complications. Conclusions: Early diagnosis is a cornerstone for the successful management of cervical tracheal injury, in which successful intubation is a mainstay to reduce mortality. Emergency surgical repair reduces mortality and complications.