Tracheal Stenosis and Postintubation Injury Flashcards
Only complete tracheal ring
Cricoid cartilage
Categories of tracheal stenosis and post-tububation injury
- Congenital tracheal stenosis
- Infectious lesions
- Extrinsic tracheal compression
- COPD
- Postintubation injuries
Morphologies of congential tracheal stenosis
- web-like diaphragm at subcricoid level (MC)
- generalized tracheal hypoplasia
- funnel-shaped narrowing
- segmental stenosis
- due to complete circular rings associated with other bronchial anomalies (RUL bronchus origin above stenosed segment)
Infectious etiologies that can cause tracheal stenoiss
- TB
- lengthy circumferential submucosal fibrosis and narrowing of distal trachea
- Histoplasmosis:
- mediastinal fibrosis with enlarged LN (compression, invasion, or erosion of RMS bronchus or carina)
Causes of external compression resulting in secondary tracheal stenosis
- Large goiters
- Vascular rings
- Innominate artery aneurysms
- Anomalous SC artery
- Mediastinal masses
- Postpneumonectomy syndrome (right sided)
- medistinal shift wih obstruction at carina or proximal LMB
TOC for inflammatory strictures (i.e. strictures due to infectious etiology)
Repeated tracheal dilation
Define “saber sheath” trachea
- Side-to-side diameter of the trachea diminishes progressively and anterior-posterior diamter increases
- Posterior aspect of cartilages approximate with coughing, causing obstruction and inability to clear secretions
Associated with COPD
Define tracheomalacia
- Tracheal rings take on shape of archer’s bow:
- Posterior membranous trachea enlongates, becomes redundant, and approaches the anterior flattened cartilage, causing near total obstruction.
- Associated with COPD
- Tx: tracheoplasty with Marlex mesh
- restores rigidity to the tracheal cartilage and plicates the redundant posterior membrane
Surgical treatment of tracheomalacia
Tracheoplasty with Marlex mesh
- Reinforce rigidity of cartiage
- Plicate redundant posterior membrane
Types of postintubation injury
- Granuloma
- Stricture
- Cuff stenosis
- Tracheomalacia
- Trachoinnominate fistula
- Tracheoesophageal fistula
Cause of tracheal granuloma
- Proliferative and cicatricial response to tracheal injury.
- Tracheostomy stoma made too large:
- turning a large flap or excising a large tracheal window
- excessive leverage placed on trachostomy tube
- infection or stoma erosion
Definiton of tracheal granuloma
A-shaped stricture due to the approximation of anterior and lateral tissue defects after tracheostomy
Definition of cuff stenosis
Tight circumferential stenosis developing 3-6 weeks after endotracheal tube removal.
Describe development of cuff stenosis
- Pressure necrosis by cuff
- Transmural erosion of all layers of trachea
- Destroys mucosa, blood supply to area
- Cartilage necrosis
- Cicatricial healing with stenosis
Tracheomalacia after intubatation occurs in what segment of the trachea
Tracheal segment between the tracheostomy stoma and the cuff
(mucosa reveals squamous metaplasia, cartilage is thinned)
Signs and symptoms of trachel stenosis/malacia
- Dyspnea on exertion
- Stridor
- Cough
- Obstructive episodes
Abnormal voice or strider is indictive of
glottic or subglottic stenosis
Cause of tracheoinnominate fistula
- Angulation of tube tip or erosion of a high-pressure cuff directly through trachea
- Low placed tracheostomy (in immiediate proximity with innominate artery)
Presentation of tracheoinnominate fistula
- Premonitory bleed (must be distinguished from granulation bleeding or irritaiton)
- Bronchoscopy with temporary removal of tracheostomy tube to confirm diagnosis
Managment of tracheoinnominate fistula
- Control of exsanguination:
- Overinflation of tracheostomy cuff
- Digital pressure against sternum through tracheostomy site
- Oral re-intubation
- Proximal debridement of artery (to healthy tissue) with vessel ligation
MCC of tracheoesophagel fistula after intubation
Ventilating cuff in trachea with feeding tube in esophagus
- Two foreign bodies compress common wall, leading to inflammation and perforation
- Often a circumferential cuff injury
Presentation of tracheoesophageal fistula after intubation
Increased tracheal secretions
Gastric distention (if positive pressure ventilation)
Managment of tracheoesophageal fistula after intubation
- Placement of new, longer tracheostomy tube with balloon below fistula
- Placement of draining g-tube and feeding j-tube
- Staged repair after patient weaned from mechanical ventilation
- Tracheal resection, closure of esophagus, interposed muscle flap
Diagnostic studies for tracheomalacia
Inspiratory/expiratory CT scans
Virtual bronchoscopy with 3D reconstructions
Temporizing measures used in managment of tracheal stenosis or airway obstruction include:
Sterioids
Racemic epinepherine
(minimize airway inflammation, edema, bronchospasm)
Method to accurately assess tracheal lesion
Intraoperative rigid bronchoscopy with serial dilation
Reason to avoid tracheal stents for stenosis
May cause severe granulations and worsen stenosis
Preferred treatment for benign tracheal obstruction
Tracheal resection and reconstruction
Reasons to delay definitive surgery for tracheal stenosis
- Acute airway inflammation
- PNA
- High dose steroids (> 10 mg prednisone / day)
Important sugical principles during tracheal resection and reconstruction
- Accurate preoperative assessmetn of location and length of stenosis
- Preservation of lateral blood supply
- Avoidance of RLN injury
Surgical approach for tracheal resection and reconstruction
- Low collar incision
- Intraoperative bronchoscopy can identify strictured segment
- Anterior dissection is peformed to ID strictured segmetn and preserve blood supply
- Circumferential dissection limite to 1-1.5 cm length at the stricture
- Traction sutures placed in distal trachea
- Tracheal transection and then intubation
- Cervical flexion to assess tension
- Proximal trachea lifted and separated from esophagus then resected
- End-to-end, tension-free anatomosis
- Strap muscles placed over suture line to buttress
