A canine model of tracheal stenosis induced by cuffed endotracheal intubation

Abstract

Postintubation tracheal stenosis is a complication of endotracheal intubation. The pathological mechanism and risk factors for endotracheal intubation-induced tracheal stenosis remain not fully understood. We aimed to establish an animal model and to investigate risk factors for postintubation tracheal stenosis. Beagles were intubated with 4 sized tubes (internal diameter 6.5 to 8.0 mm) and cuff pressures of 100 to 200 mmHg for 24 hr. The status of tracheal wall was evaluated by bronchoscopic and histological examinations. The model was successfully established by cuffed endotracheal intubation using an 8.0 mm tube and an intra-cuff pressure of 200 mmHg for 24 hr. When the intra-cuff pressures were kept constant, a larger sized tube would induce a larger tracheal wall pressure and more severe injury to the tracheal wall. The degree of tracheal stenosis ranged from 78% to 91% at 2 weeks postextubation. Histological examination demonstrated submucosal infiltration of inflammatory cells, hyperplasia of granulation tissue and collapse of tracheal cartilage. In summary, a novel animal model of tracheal stenosis was established by cuffed endotracheal intubation, whose histopathological feathers are similar to those of clinical cases of postintubation tracheal stenosis. Excessive cuff pressure and over-sized tube are the risk factors for postintubation tracheal stenosis.

Postintubation Tracheal Stenosis Evaluated by Endobronchial Optical Coherence Tomography: A Canine Model Study

“…Respiration 2020;99:500-507 DOI: 10.1159/000506882 study [3] had introduced a canine model of tracheal stenosis induced by endotracheal intubation, indicating that proliferation of granulation tissue and ischemic necrosis of tracheal cartilage were found 2 weeks after extubation.…”

“…The beagle model of PITS was established as described in our previous study [3]. Under general anesthesia, endotracheal intubation was performed under laryngoscopic guidance.…”

Mucosal injury following short‐term tracheal intubation: A novel animal model and composite tracheal injury score

“…We needed to demonstrate functionality of sensors, and absence of obvious injury in a viable and translational animal model. Previous animal models were considered unsuitable for a variety of reasons including use of ambulatory animals, size of the animal, use of hypoxic gas mixtures to accelerate damage, or prolonged periods of ventilation . In this study, we describe an animal model suitable to assess the efficacy of sensors and influence of endotracheal cuff design, material, and cuff pressure management.…”

“…Animal models have been used to examine histopathological changes, but have been hindered by the perception that long periods of intubation, or excessive cuff pressures were required to induce measurable injury. [15][16][17][18][19] In order to address this, Gordin et al described a piglet model in which hypoxic gas mixtures were used to accelerate ischemic injury. 20 Although this model proved successful in inducing significant injury, the results may have been confounded by use of hypoxic conditions.…”

“…Previous animal models were considered unsuitable for a variety of reasons including use of ambulatory animals, size of the animal, use of hypoxic gas mixtures to accelerate damage, or prolonged periods of ventilation. 19,20 In this study, we describe an animal model suitable to assess the efficacy of sensors and influence of endotracheal cuff design, material, and cuff pressure management. We further describe the effect of short-term intubation, at conventional cuff pressures, on histopathology of the tracheal epithelium and report a novel histopathological scoring system.…”