Tracheal Surgery Flashcards
2 functions of the annular ligaments of the trachea:
Shape
length accomodation
Is the trachealis muscle on the dorsal or ventral aspect?
Dorsal connection
What important structure lives on the lateral aspect of the wall of the trachea?
Recurrent Laryngeal nerve – laryngeal dysfunction if damage on the lateral side of trachea
What 2 muscles are split when doing the cervical ventral midline approach?
Sternohyoideus m.
Sternothyroideus m.
4 structures in the carotid sheath:
Carotid
Vagosympathetic trunk
Vagus n.
Internal Jugular vein
For the cranial cervical trachea, what surgical approach is used:
Cervical Ventral Midline
Approach the trachea from the ____ side :
Right
For the caudal cervical & cranial thoracic trachea, what surgical approach is used:
Median Sternotomy
Name the ICS for Intercostal thoracostomy:
Right 3rd ICS ==> Cranial thoracic trachea
Right 4th ICS ==> Tracheal bifurcation
What process/ surgical dz is tracheal collapse:
Degenerative change – progressive, irreversible degeneration of lower airway (Laxity of the trachealis muscle = weakness of tracheal rings)
Factors cause increased weakness/ pliability in tracheal collapse:
Decreased water retention secondary to loss of glycoprotein and GAG.
Decreased Calcium and chondroitin.
Name 3 things associated with the progressive cough seen in squamous metaplasia:
- Squamous Metaplasia
- Reduction of ciliated cells
- Increased viscosity to secretions
Cor pulmonale (aka Right heart failure) is associated with tracheal collapse. Name the 2 factors associated with this:
- Pulmonary Hypertension
2. RV enlargement
Most common secondary factor in tracheal collapse:
OBESITY – fat deposits in the thoracic cavity causes inability for the lungs to expand creating resp probz.
Wt loss = minimize CS
Name the 4 secondary factors of tracheal collapse:
- Obesity
- Enviromental allergens
- Respiratory irritants - Cig smoke, aerosol sprays, fireplaces
- Kennel cough
– of 100 cases of tracheal collapse, 55% had >1 coexisting disease.
Is tracheal collapse common in small or large breed dogs?
Small breed or toy breed dogs
– Yorkie, Poms, mini/toy poodles, Chihuahuas, and pugs
What age is most commonly effected for tracheal collapse:
Middle Age dogs
- signs at an earlier age consistent with more severe dz.
- no evidence of sex predilection for tracheal collapse.
“GOOSE HONKING” cough is a characteristic sign of:
Tracheal collapse
–progressive
Clinical signs of tracheal collapse are:
- Goose honk cough
- wax and waning dyspnea
- exercise intolerance
- cyanosis
- syncope
Differentials for tracheal collapse:
- Heart dz / Cardiomegaly
- Kennel cough
- Bronchitis
- Pneumonia
- other lower airway dz (neoplasia/ infectious/inflammatory/ FB)
Important diagnostic for tracheal collapse:
IMAGING – shows severity & location
others diagnostics are based on: Signalment / history/ CS / PE
T/F: Radiographs have variable sensitivity & low specificity for tracheal collapse but can be useful to determine if collapse if cervical or thoracic.
True
– must image entire trachea
If it is a cervical collapse, the collapse happens during inspiration or expiration?
Inspiration
- Cervical = Inspiration [CI]
- Thoracic = Expiration [TE]
if it is a thoracic collapse, the collapse happens during inspiration or expiration?
Expiration
- Cervical = Inspiration [CI]
- Thoracic = Expiration [TE]
What is the term that refers to ‘Real time radiographic imaging’ that allows visualization of the entire respiratory cycle:
Fluoroscopy
Disadvantage: This method has had false positives reported & hard to interpret.
Advantage: No sedation or anesthesia is typically required (may require Anxiolytic for dyspnea)
Gold Standard diagnostic for tracheal collapse:
TRACHEOSCOPY
- allows direct visualization of collapse (Grading of severity)
- allows visualization of tracheal mucosa & dorsal tracheal membrane
Tracheoscopy allows visualization of:
- collapse
- tracheal mucosa
- dorsal tracheal membrane
Advantage of Tracheoscopy:
Can obtain samples for cytology & bacterial culture/ sensitivity.
Disadvantage of Tracheoscopy:
Requires anesthesia which may incite DYSPNEIC EPISODE
If the lumen reduction is 25%, what grade is the tracheal collapse:
Grade 1
If the lumen reduction is 75%, what grade is the tracheal collapse:
Grade 3