Low Respiratory Surgery Flashcards
The dorsal tracheal membrane is made of these three things:
- Mucosa
- Connective tissue
- Trachealis muscle
The vascular supply of the trachea and bronchi is ______, from cranial and caudaul _____ and _____ arteries.
Segmental; thyroid, bronchial
The recurrent laryngeal nerve lies at the ______ edges of the trachea ____ to the heart.
dorsolateral; cranial
Two muscles to cut through to get to the ventral aspect of the cervical trachea:
- Subcutaneous trunci m.
- Sternohyoideus m.
The surgical approach to the thoracic trachea is from the ____ side, at the ___rd ICS.
Right (esophagus is on the left), 3rd ICS
Poster child for tracheal colapse
Yorkie (mini and toy breeds)
Clinical signs of tracheal collapse
- Coughing
- Dyspnea
- On inhalation: cervical trachea collapsed
- On exhalation: thoracic trachea collapsed
Tracheal collapse pathophysiology
- Congenitally hypoplastic or fibrodystrophic cartilaginous rings
- Redundant or weak dorsal tracheal membrane
- May involve both cervical and thoracic trachea
- May extend to mainstem bronchi (and lower)
Four grades of tracheal collpase are based on _____ .
% of lumen reduction
Grade I - 4 Tracheal Collapse
- Grade I - 25% lumen reduction
- Grade II - 50% lumen reduction
- Grade III - 75% lumen reduction
- Grade IV - almost no lumen
Medical treatment is typically preferred (vs surgery), especially in grades I and II tracheal collapse. True or False.
True
Medical treatment of tracheal collapse
- Cough suppressants
- Bronchodilators
- Antibiotics (if complicated by bacterial infection)
- Control complicating factors - obesity, heat stress, leash irritation (harnes vs collar)
Surgical treatment of tracheal collapse
- When medical treatment cannot control clinical signs
- Limited ability to alleviate bronchial collapse
- Intraluminal stents or extraluminal rings/prostheses
Dorsal tracheal membrane prication is not typically performed becuase it requires relatively normal tracheal cartilages. True or False.
True
Extraluminal prosthesis are made from _______ syringe, or syringe cases.
Polypropylene syringe
Which is preferred:
Total ring prostheses or spiral-shaped prosthesis?
Total ring prostheses are preferred. Spiral shaped ones restrict blood supply.
How do you treat tracheal hypoplasia?
No surgical care or treatment, simply use smaller endotracheal tube.
Two common causes of internal injury to the trachea or bronchi?
- Intubation can damage trachea
- Foreign bodies
Tracheal stenosis is ____ due to trauma.
Scar tissue
Treatment options for tracaheal stenosis
Most commonly we do a resection/anastomosis. Can also do a bougienage, balloon dilatation, and or stent.
Predominant clinical sign of blunt or penetrating tracheal trauma
Persistent peritracheal, subcutaneous, and/or mediastinal emphysema
Most tracheal tears resolve without surgical intervention. True or False.
True
Temporary tracheostomty are almost always necessary to decrease airway resistance in tracheal lacerations. True or False.
False - rarely necessary!
List the three anastomotic techniques ofr tracheal resection/anastomosis, and which one is preferred.
- Split-cartilage technique - preferred b/c results in less stenosis from healing
- Annular ligament-cartilage technique
- Interannular technique
In a split cartilage technique, two rings of _______ are split, and the sutures are placed on either side of the rings, through the ______ _____.
cartilage; annular ligaments
Make sure to place sutures in the ______ muscle before other sutures when performing a tracheal anastomosis.
trachealis muscle
Tension-relieving sutures are placed around rings _____ to primary repari to minimize stenosis. (distant or close).
Distant
Indications for tube tracheostomy
Life-threatening upper airway obstruction.
Inhalation anesthesia for upper respiratory and intraoral surgery.
Removal of secretions and aspriated material.
When we just want to bipass the main airways, and not ventilate for anesthseia, do we prefer tubes with or without cuffs?
Without cuffs - because cuffs can accumulate secretions
Tube Tracheostomy Preparation:
Preparation of neck for ventral cervical incision from the _______ caudally for a distance equal to __ or ___ tracheal rings.
cricoid cartilage caudally; distance equal to 3-4 tracheal rings
Surgical tehchnique for tube tracheostomy
- Ventral midline incision from cricoid cartilage to about 3-4 cm caudally
- Separate sternohyoideus muscles on midline
- Transverse interannular incision between trachea rings 2 and 3 (or 3 and 4)
- Knotted stay sutrues around rings 2 and 3
- Insert and secure tube with umbilical tapes tied behind the neck.
When performing a tube trahceostomy it is important to outline ____ and _____ cartilages on the skin before incision.
Thyroid and cricoid
The ideal skin incision site for tube tracheostomy is more ____. (caudal or cranial).
Cranial