Resp.&Thoracic SX- LA Flashcards
What is the primary source of upper airway resistance.
Nasal valve, rostral nasopharynx & larynx
- oral cavity has tremendous resistance
What are 2 signs of upper airway dysfunction?
- Poor performance (d/t decreased ventilation)
2. Increased noise (dt increased turbulence)
Aside from a resting endoscopy, how can you gauge laryngeal function at rest?
Nasal occlusion
Swallow reflex
Slap test (slap wither while feeling muscular process)
What are you evaluating with an exercising endoscopy?
Dynamic dysfunction (high speed treadmill or overground)
What age is sinoscopy not useful?
Young horse because teeth in the maxillary sinus
Diagnostics- rads
Observe paranasal sinuses and dental arcade
Diagnostics- US
Laryngeal US (muscular atrophy & abnormal anatomy) - Bone limits other locations
Diagnostics- CT
Method of choice for dental arcades ¶nasal sinus
No superimposition
What causes flow artifact in MRI?
Blood flow from large vessels
What is a false diverticulum in horse nare?
Alar fold
Can you see redundant alar folds on endoscope?
No, because not in nostril
Its often in standard breeds
Horners syndrome in horses
Engorged nasal mucosa limits airflow
Wry nose
Occurs when maxillary and mandibular teeth dont line up
Often does not need surgery if can still eat/drink
Where do all sinus drain?
Into nasal cavity via nasomaxillary aperture/ middle meatus
Primary and secondary cause of paranasal sinuses?
Primary- strep spp.
Secondary- dental dx, mass, trauma
DX: endoscopy or rads (fluid line)
Landmarks for trepination:
Frontal- midline to medial canthus
Caudal maxillary sinus- ventral to medial canthus
Rostral Maxillary Sinus- can use rads to find
Paranasal sinus:
When enlarged see facial deformation +/- airway obstruction
Curative with surgical debridement
Good prognosis, but for athlete depends on nasal passage distortion
Sinus neoplasia
MC SCC
Causes facial deformity in older horses +/- airway obstruction
Tx: debridement, radiation and chemo
PX: poor
Progressive ethmoid hematoma
CS: mild epistaxis (unilat),
Rare- facial deformity &airway obstruction
Tx: intralesional formalin, laser photoablation, sx removal
Does the pharynx have rigid support?
No
What is lymphoid hyperplasia?
Occurs in young horses dt immune stimulation
-usually no CS or TX needed
Dorsal displacement of the soft palate
Intermittent > persistent (rest)
Key: noise during expiration!
Dx: exercising endoscopy (intermittent) or resting endoscope (Persistent)
TX: laryngeal tie forward
Recurrent laryngeal neuropathy
Demyelination and axonopathy of RLN, causing paralysis of intrinsic laryngeal muscle [CAD]
CS: inspiratory obstruction & noise at exercise
MC: left side and large horse (draft, TB)
DX: resting endoscopy & laryngeal US
What is the sx treatment for RLN?
Prosthetic laryngoplasty (tie-back)
Guttural pouch mycosis
Focal fungal infection (aspergilus sp.) targeting arteries and nerves—> hemorrhage/life threatening (50% die)
CS: epistasis, horners, nasal discharge (pus)
DX: scope
