Kapitel 102 - Trachea and bronchi Flashcards
What marks the boarder between the upper and lower respiratory tract?
The cricotracheal junction
What vessels supply the trachea?
Cranial and caudal thyroid arteries
What is the main innervation of the tracheal mucosa and the trachealis muscle?
Right vagus and recurrent laryngeal nerve
What diagnostic tool is required for diagnosis of bronchomalacia?
Tracheobronchoscopy
For a bronchial lavage to be considered diagnostic, how much if the infusate instilled must be retrieved?
33%
What are the indications for a temporary tracheostomy?
for any condition resulting in upper airway obstruction, including:
i. brachycephalic airway syndrome
ii. laryngeal paralysis
iii. cervical trauma
iv. laryngeal foreign bodies
v. neoplasia
vi. anaphylaxis.
What is the recommended tracheostomy tube size?
the outer diameter of the tracheostomy tube should not exceed 75% of tracheal diameter
how often should a tracheostomy tube be replaced?
a. tubes should be replaced twice daily; exchange can be required as frequently as every 4 to 6 hours after initial placement because of excess airway secretions.
b. single-lumen tubes must be removed and replaced every time cleaning is necessary, double-lumen tubes have a removable cannula that can simply be exchanged.
Airway suctioning is another way to keep the tube clean. For how long should suction be? And what other possible effects if this should be considered?
a. Not more then 10-12 sec. More can lead to severe atelectasis and hypoxia
b. Can also cause a vagal response resulting in gagging, retching or bradycardia. ECG is recommended during the suction procedure.
What is the most common long term complication after temporary tracheostomy?
a. Stomal stenosis
i. (two sites have been identified: at the stoma site itself and at the level of the cuff or tube tip)
What is the most common indication for a permanent tracheotomy?
laryngeal masses in cats and laryngeal paralysis or collapse in dogs
What has been reported as the most common complication of a permanent tracheostomy?
Aspiration pneumonia
List three tension-relieved techniques that can be used for tracheal anastomosis
a. Tension-relieving sutures placed several rings proximal and distal to the anastomosis
b. fixed ventroflexion of the neck
c. release of the annular ligaments with preservation of mucosa
name two tracheal anastomotic techniques
a. The “split cartilage” technique - involves placing the suture around divided tracheal rings
b. The “annular ligament cartilage” - involves placement of the suture around adjacent tracheal rings through the annular ligament
What are the surgical approaches to the trachea?
a. Cervical trachea
* Ventral midline approach
b. Thoracic inlet
* Ventral midline combines with a proximal sternotomy
c. Intrathoracic trachea
* Right sided 3rd-5th intercostal thoracotomy
(azygos vein is identified, ligated and transected for maximal exposure)
When does patients with tracheal avulsion usually present?
2-3 w after the injury, presenting with airway obstruction.
Have can you histologically differentiate an congenital vs an aquired esophagotracheal fistula?
Congenital fistulae are lined with squamous epithelium rather than granulation tissue because they occur from lack of normal separation during embryogenesis and not from trauma
Which diagnostic tool provides the most significant diagnostic information for tracheal collapse?
Tracheoscopy
1Nme the tracheal collapse grading system
a. Grade 1: 25% collapse
b. Grade 2: 50%
c. Grade 3: 75%
d. Grade 4: 100%
List the different surgical techniques for treatment of tracheal collapse
a. Extraluminal Prosthetic Tracheal Rings
b. Extraluminal Spiral Prosthesis
c. Intraluminal Stents
What are the advantages with intra luminal stents?
a. shortened anesthetic time
b. immediate improvement in clinical signs related to tracheal collapse
c. the ability to place the stent within the cervical or thoracic regions or entire trachea in a noninvasive manner.
What is the appropriate size of tracheal stent?
a. The stent should be 10-20% wider than the widest part of the trachea, measured on a positive pressure radiograph.
b. The minimum length should span the area of collapse when fully expanded, however preferably it spans the whole area of the traches rather than only the collapsed area.
Where is the ideal location of stent placement?
1 cm caudal to the cricoid cartilage and 1 cm cranial to the carina
i. (Stent placement can be achieved with fluoroscopic guidance or direct visualization)
List possible complications of tracheal stenting
a. stent fracture
b. stent migration
c. tracheitis
d. collapse beyond the stented region
e. obstruction of the stent lumen with granulation tissue
f. tracheal rupture
g. uncommon complications after stent placement include rectal prolapse and perineal hernia, presumably from refractory paroxysmal cough
- what are your treatment options is case of stent fracture?
a. Fist aggressive medical management. If the dog remains severely symptomatic:
i. a new stent can be deployed within the lumen of the fractured stent
ii. extraluminal rings can be placed around the fractured area
iii. or the stent can be removed via tracheotomy or resection and anastomosis
which lobe is most commonly affected by congenital lobar emphysema?
a. Right middle lobe
(but multiple lodes can be affected in the same individual)
What radiographic imagine is shown? What condition it this associated with?
a. Situs invertus - the thoracic and abdominal viscera in a mirror image to their normal orientation
b. Ciliary Dyskinesia
