Nasal & Upper Respiratory Surgery Flashcards
What makes up the upper respiratory tract?
nose to larynx
What is a common complication after nasal surgery? How can it be avoided?
stenosis can lead to fluid buildup and infection - stents can be placed to minimize narrowing, but some narrowing is expected following their removal
(TISSUE DOES NOT HEAL WELL)
In what situations is a nasal planum resection most likely necessary? What can help for planning?
SCC and other neoplasia
CT —> complete most commonly done, but can be done unilateral
Nasal planum resection:
How are nosectomies closed?
skin is brought down to the turbinates, leaving the animal with one large nostril
How can scarring following a nosectomy be avoided?
tack skin line down to the mucosal lining of turbinates
What are the 2 most common complications associated with nosectomies?
- dehiscence
- stenosis
Other than stents, how can complications following nosectomies be avoided?
radiation can be used to decrease cell proliferation and steroids can decrease inflammation
What fungal diseases are most common in the nasal cavity?
Aspergillosis and Rhinosporidiosis
(Nocardiosis is common in the “fungal belt” in KY)
What does nasal cavity lysis typically indicate?
fungal disease or tumors
What is characteristic of nasal Aspergillosis? What does it typically mimic? Where is it most commonly found?
infection of the nasal cavity and often frontal sinus by large colonies of green fungal hyphae
nasal cavity, paranasal sinus, invasion of cranial vault is less common
How is nasal Aspergillosis treated? What complication is possible?
1% Clotrimazole over one hour - place a 24 Fr foley catherter into the oral cavity dorsal to the soft palate and a 10 Fr infusion catheter into each nostril - inflate the balloon to occlude the nostril
leakage into lungs can cause fatal pneumonitis
What is trephination? How is it done into the frontal sinus?
creating a burr hole into the skull
- include the zygomatic process of the frontal bone
- midline of skull
- ventral of orbital rim
(can use Michel trephine or large Steinmann pin)
What are 4 major surgical approaches to nasal cavity surgery?
- mini/modified rhinotomy between the eyes - more minimally invasive and allows for suction and lavage
- dorsal - large window flap is made and wired back down gives large access to nasal cavity and frontal sinus
- oral - through gumline
- ventral - through hard palate gives good access to ventral meatus, caudal nasal cavity, and choanae, but is prone to dehiscence
Nasal cavity surgery, oral approach:
Why is endoscopy difficult for assessing the nasal cavity?
cannot go past healthy choana, discharge may disrupt views, and may only get a small biopsy
CT of nasal cavity:
turbinate destruction in both cavities through the hard palate —> imaging of choice, good for hard tissue
Radiograph of frontal sinus:
increased density of the right frontal sinus may represent fluid or neoplasia
(open mouth, no mandible or tongue superimposing)
What are 3 primary complications of brachycephalic obstructive airway syndrome?
- stenotic nares - diminishes airways
- elongated soft palate
- hypoplastic trachea - contracted, stented
What are 2 secondary complications of brachycephalic obstructive airway syndrome?
- everted laryngeal saccules
- laryngeal collapse
How do animals with BOAS typically present anatomically?
- 100% elongated soft palate
- 50% stenotic nares
- 30% everted laryngeal saccules, laryngeal collapse, or both
CT of brachycephalic vs. mesocephalic skull:
What does prolonged obstruction due to BOAS lead to?
pharyngeal edema or collapse
What is the goal of BOAS surgery? In what 3 ways is this done?
reducing intra-airway pressure
- shortening of the soft palate (staphylectomy)
- removal of laryngeal saccules
- widening nares
What is the gold standard to diagnosing BOAS?
laryngoscopy —> can view obstruction from soft palate or laryngeal saccules
What is the point of thoracic and head/neck radiographs when diagnosing BOAS?
THORACIC - rule out lower airway disease
HEAD/NECK - assess soft palate length and screen for hypoplastic trachea
When should contrast esophagography be done for diagnosing BOAS? Tracheobronchoscopy?
if any esophageal disease is suspected
lower airway disease is suspected, can confirm hypoplastic trachea
How is BOAS managed?
- strict weight loss program
- reduced exercise
- harness
- short-term steroids for inflammation
- sedatives to decrease panting and nervousness (trazodone)
- avoid hot environments
- surgery
Brachycephalic airway:
Why do brachycephalic animals have a hard time breathing?
bred to have a short muzzle, which causes the nasal passages and oropharynx to also be shorter, containing the folds seen on the face
What 4 things does the term brachycephalic syndrome refer to?
- elongated soft palate
- stenotic nares
- everted laryngeal saccules
- tracheal collapse (may require stents)
What are the 6 major symptoms of brachycephalic airway syndrome? What can make these symptoms worse?
- mild or life-threatening respiratory distress
- snorting
- noisy breathing (STERTOR)
- excessive panting
- exercise intolerance
- cyanosis
heat, stress, or excitement
What 4 tests are required for diagnosing BOAS?
- laryngoscopy**
- thoracic radiographs
- tracheoscopy
- fluoroscopy
How is the soft palate affected by BOAS?
longer and thicker than normal, which interferes with airflow
What is the purpose of the soft palate?
occludes nasopharynx during swallowing and will normally overlap the epiglottis by 1-2 mm
Elongated soft palate:
What perioperative medication is utilized for BOAS surgery? What are the 3 techniques?
corticosteroids —> decrease inflammation
- freehand (clamp/crush) - old technique with a lot of bleeding that can lead to aspiration
- laser freehand
- ligasure - tissue sealing device that uses pressure and electrically generated bipolar energy that contacts the tissue and the increased temperature seals up to 7 mm in diameter
What 2 landmarks are used for proper resection of the soft palate?
- soft palate naturally overlaps epiglottis by 1-2 mm
- laterally, the soft palate should extend to the caudal border of the tonsillar crypt
How is the freehand technique for soft palate resection done?
amputate the soft palate to midline with scissors on one side, suture to midline, then amputate the remaining palate and suture
What are the 4 advantages to laser free hand technique over freehand technique for soft palate resection?
- rapid
- virtually no blood loss allows for excellent visualization
- minimal post-op inflammation
- reduced post-op discomfort
What are the major acute and chronic complications of palatectomies?
ACUTE = hemorrhage, inflammation
CHRONIC = undershortening* (redo), overshortening leads to nasal reflux and aspiration
What is a folded-flap palatoplasty?
soft palate is thinned by excision of a portion of the oropharygneal mucosa, underlying soft tissue, and part of the levator levi palatini
What are stenotic nares? What do they cause?
nostrils are excessively narrow due to a congenital defect of nose cartilage
air cannot flow smoothly through the narrowed nostril, leading to increased respiratory effort and noisy breathing
What is the purpose of the alar wing and fold in the nose?
during exercise, the alar wing and fold are abducted to enlarge the naris
When is the best time to correct stenotic nares? What is the goal to this surgery?
SEVERE = 3-4 months
MILD = 6 months
lateralize the alar wing and fold to facilitate air passage through the nostril
In what 3 ways are stenotic nares surgically managed?
- wedge resection - horizontal, vertical, dorsolateral
- amputation of the alar wing +/- fold
- alapexy
How are dorsolateral wedge resections performed?
take out a wedge in the nose close to the skin and connect the remaining nose to the skin, lateralizing the alar wing and fold
What equipment is used to perform wedge resections?
- cold steel
- electrosurgery
- laser
What are everted saccules?
swelling of the vocal fold lining secondary to tubulent air flow
- can become so swollen that they protrude into the main airway
How are everted saccules removed?
same ligasure procedure done with the soft palate resection
What monitoring must be done for brachycephalic breeds? When can patients be extubated?
monitor for difficulty breathing, coughing, regurgitation, or aspiration of blood
patients must be BAR —> completely awake and swallowing
What is a laser-assisted turbinectomy?
removal of obstructed nasal turbinate tissue using a diode laser to shape a patent nasal airway
What is the purpose of a tracheal trochar/tracheostomy? When is it typically done in emergency and planned procedures?
bypass the upper airway and deliver oxygen to the lungs
- EMERGENCY = craniofacial trauma
- PLANNED = before oral surgery
How are tracheal trochars performed?
a large bore needle or a catheter is placed between tracheal rings and directed distally into the trachea to support airflow
How are patients positioned for tracheostomies? Where are the skin, muscle, and tracheal incisions made?
on their back with forelegs pulled down their side
- SKIN: midline from cricoid cartilage edge back ~2-3 cm
- MUSCLE: midline thin white line at sternohyoideus and sternohyoideus provide minimal blood supply
- TRACHEA: expose the first 6-7 rings and incise between the 3rd-4th and 4th-5th rings no more thsn hald the circimference (1/3)
What is done after the skin, muscle, and trachea are incised in a tracheostomy? How is it closed?
slip in a tracheal tube and secure it around the neck
appose muscle and skin above and below tube
How far should a tracheal tube be put down during a tracheostomy?
should not extend past the sternum, or it may end up in one bronchus
What causes laryngeal collapse? What are the 3 stages?
loss of cartilage rigidity allows medial deviation of the laryngeal cartilage
- saccule eversion
- collapse of cuneiform process of the arytenoid cartilage (aryepiglottic collapse)
- collapse of corniculate process of arytenoid cartilage (corniculate collapse)
What is laryngeal paralysis? What are 3 possible causes?
complete or partial failure or arytenoid cartilages and vocal folds to abduct during inspiration
- dysfunction of laryngeal muscles
- recurrent laryngeal or vagus nerve dysfunction
- cricoarytenoid ankylosis
What are the 4 major surgical treatments for laryngeal paralysis?
- unilateral arytenoid lateralization
- partial laryngectomy (bilateral vocal form resection, partial arytenoidectomy)
- reinnervation of laryngeal musculature
- permanent tracheostomy
What are the most common malignant and benign laryngeal tumors?
MALIGNANT = SCC, lymphoma, osteosarcoma, fibrosarcoma, rhabdomyosarcoma, melanoma, MCT, granular cell myoblastoma
BENIGN = lipoma, oncocytoma, rhabdomyoma
What are the most common malignant and benign tracheal tumors?
MALIGNANT = osteosarcoma, chondrosarcoma, lymphoma, MCT, adenocarcinoma, SCC, rhabdomyosarcoma, melanoma
BENIGN = osteochondroma, oncocytoma, leiomyoma, chondroma, polyp
What are the 2 major options for surgical treatment of laryngeal tumors?
- partial laryngectomy
- total laryngectomy with creation of a permanent tracheostomy
What is tracheal collapse? What are the 4 multifactorial causes?
tracheal obstruction caused by cartilage flaccidity and flattening
- genetic
- nutritional
- environmental
- degenerative
What are the 4 grades of tracheal collapse?
- relatively normal tracheal cartilage anatomy where redundant dorsal membranes decreases luminal diameter by 25%
- mild to moderate flattening of tracheal cartilage with 50% loss of luminal diameter
- severe flattening of the tracheal cartilage with 75% loss of luminal diameter
- complete obstruction, lumen is obliterated
Tracheal collapse grades:
What are 2 options for collapsed trachea repair?
- extraluminal stent - prosthetic tracheal rings or spirals (polypropylene syringe case) placed from larynx to heart base tacked every cm
- endoluminal stent - minimally invasive self-expanding elastic implant is placed using tracheoscopy or fluoroscopy
