Subglottic injury: a clinically relevant animal model

Area of Science:

• Otorhinolaryngology
• Pathology
• Animal Models

Background:

• Endotracheal intubation can lead to subglottic stenosis (SGS).
• Developing a reproducible animal model is crucial for studying SGS pathogenesis and testing interventions.
• Existing models may not fully capture the acute/subacute injury spectrum.

Purpose of the Study:

• To establish a clinically relevant and reproducible animal model for subglottic injury.
• To investigate the histological and morphometric changes following intubation in a juvenile rabbit model.
• To provide a foundation for future studies on preventing or treating acquired subglottic stenosis.

Main Methods:

• Prospective randomized control pilot study using juvenile New Zealand White rabbits.
• Intubation with oversized endotracheal tubes for 1 week, followed by sacrifice and larynges harvest.
• Histological techniques and gross morphology analysis to assess subglottic injury, with unintubated animals as controls.

Main Results:

• Intubated rabbits showed significant histopathology: ulceration, inflammation, granulation tissue, perichondritis, and chondritis.
• Increased lamina propria thickness (P = .0013), mucosal thickness (P ≤ .0001), and goblet cell density (P = .014).
• Significant decrease in acidic mucin (P = .0001) and increase in mixed mucin types (P = .0013).

Conclusions:

• The developed rabbit model reliably replicates acute/subacute subglottic injury from intubation.
• Findings align with early histological changes observed in acquired subglottic stenosis.
• This model can be used to evaluate therapies aimed at limiting SGS progression.