Flashcards in Stridor Deck (59):
What is a term used for horses to describe noisy breathing in general?
Can a horse manifest stridor in the absence of respiratory distress?
How is respiratory distress define here?
- Prolonged dyspnea manifested
How does a horse with stridor not associated with distress usually appear at rest?
Normal with no difficulty breathing observed.
What are 4 examples of causes of stridor not associated with distress?
- Dorsal displacement of soft palate (DDSP)
- Epiglottic entrapment (EE)
- Laryngeal hemiplegia
- Arytenoid chondritis
Causes of stridor not associated with distress are usually temporary obstructions due to what type of changes in the upper airway?
Associated with what?
- Dynamic changes
- Some underlying disease/abnormality
Many, but not all, dynamic airway obstruction cases have a history of what?
An abnormal noise
What are 5 other terms that you may hear used to refer to dorsal displacement of the soft palate (DDSP)?
- Choking up
- Flip their palate
- Swallow their tongues
- Elongated soft palate
- Soft palate paralysis or paresis
What are the 2 types of DDSP?
Which is more common: intermittent or persistent DDSP?
Is DDSP considered a significant performance-limiting condition in the horse?
When is it seen?
- Only seen at exercise
Even though some horses are "corrected" for DDSP by trimming the caudal margin of the soft palate, there is usually no evidence of what?
So what are they thinking??
- No evidence of overabundant tissue...which is why doing this makes no sense...
- Thought is that the surgery causes fibrosis and "firming" of the caudal palate edge
Typically, persistent DDSP are what in origin?
Neurogenic in origin
Causes of which form of DDSP are often multi-factorial and varied?
What are 6 possible causes of intermittent DDSP?
- Thyroid muscle dysfunction
- Retraction of the tongue
- Retraction of the larynx by extensive head flexion
- Hypoplastic epiglottis
- Upper and lower respiratory disease
What are 6 possible clinical signs that can be seen with DDSP?
- Exercise intolerance
- "Chocking": loud gurgling or fluttering noise
- Generation of noise
- Nervous/tense horse
- Excessive neck stretching and swallowing
- Coughing while eating
What is a sign of exercise intolerance seen in race horses with DDSP?
When is the seen?
- Speed slowing dramatically during racing - "quitting"
- Usually last half of race
Horses with DDSP are often presented for what reason?
Generation of a noise
Approximately what percentage of DDSP cases do NOT make a noise?
During what phase(s) of respiration is noise generated with DDSP?
What is the main component?
- Inspiration and expiration
- Mainly expiratory component
What is a possible sign that can be seen with DDSP that is due to air during expiration being expelled into both the nasopharynx and oropharynx?
Which way is air normally expelled during expiration?
- Puffing of the cheeks
What are 4 aspects of diagnosing DDSP?
- Clinical signs
- Expiratory noise on sound analysis
What are 2 normal features of an epiglottis that can be seen that tells you it is positioned normally when viewing through an endoscope?
- Serrated edges
- Distinct surface vasculature
A horse affected by DDSP will have difficulty doing what?
Replacing epiglottis in normal position after swallowing.
Ventral displacement of epiglottis relative to the soft palate for longer than 8 seconds during high speed treadmill endoscopy is diagnostic for what condition?
Many horses with DDSP may exhibit small ulceration where?
This occurs secondary to what?
- Caudal free border of soft palate.
- Repeated trauma of dislocation, especially when coughing.
What are 3 things to watch for when endoscoping a horse suspected of DDSP?
- Pharyngeal hyperplasia
- Hypoplastic epiglottis
What is the approximate normal length of an epiglottis of a Thoroughbred?
Of a Standardbred?
- TB: 8.56 cm
- SB: 8.74 cm
Hypoplastic epiglottis is associated with what 2 conditions?
What are 3 overall considerations in the treatment of DDSP?
- Treat other concurrent treatable conditions
- Treat conservatively
- Treat surgically
What are 2 conditions that can present concurrently with DDSP?
What are 3 examples of conservative treatments for DDSP?
- Change poll flexion
- Tongue tie
- Throat support device (TSD)
What is a possible treatment for DDSP where caudal retraction of the larynx is prevented?
What does this treatment also hopefully increase?
- Tongue tie
- Contact surface of the palate and epiglottis
Where is the tongue tied when treating DDSP?
Near frenulum to inter-dental space of lower jaw.
What is an example of a TSD that can be used in the treatment of DDSP?
Cornell DDSP collar
In what position does a throat support device (TSD) hold the larynx to prevent DDSP from occurring?
Positions larynx more rostrally and dorsally.
What are 5 possible forms of corrective surgery for DDSP?
- Laryngeal tie-forward
- Sternothyrohyoid myectomy
- Soft-palate thermoplasty
- Epiglottic augmentation
Which form of surgical correction for DDSP is the most recent that has seen with good success by positioning the larynx more rostrally and dorsally?
What is a form of surgical correction for DDSP that involves resecting a portion of the soft palate, typically creating scarring (stiffening) of the palate free border?
Which type of surgical treatment of DDSP involves injecting polytetrafluoroethylene into the lingual submucosa, causing an increase in rigidity that does not change the length?
What is an upper airway condition that can produce exercise intolerance, respiratory noise and occasional coughing, especially when eating?
What are 2 types of loose epiglottic tissue that can envelop the epiglottis with epiglottic entrapment?
What type of tissue is quite loose and redundant which allows for epiglottic elevation during deglutition with epiglottic entrapment?
Epiglottic entrapment is associated with hypoplastic epiglottises in about what percentage of cases?
Epiglottic entrapment can occur concurrently with other disease such as what?
The displaced tissue seen with epiglottic entrapment causes an impediment to airflow, which creates what?
Turbulent flow resulting in a noise.
Is epiglottic entrapment more commonly intermittent or persistent?
What are 4 examples of clinical signs that can be seen with epiglottic entrapment?
- Exercise intolerance
- Inspiratory and expiratory noise
- Chronic cough, especially when eating
What are 3 forms of diagnosis used for epiglottic entrapment?
- Clinical signs
What is seen on endoscopy with epiglottic entrapment?
Loss of scalloped edge of epiglottis.
About 45% of epiglottic entrapment cases show what sign?
This can lead to what?
- Ulcer in membrane
- Can erode through and have the apex of the epiglottis protrude through the opening.
What are 2 general methods of treatment for epiglottic entrapment?
If the epiglottic entrapment is of short duration, what type of conservative treatment can be tried?
What is the likelihood of recurrence?
- Stall rested for 1 week with possible anti-inflammatory administration.
- EE is likely to recur once training is resumed.
What are 3 forms of surgical treatment for epiglottic entrapment?
- General surgery under general anesthesia
- Standing endoscopic resection with blade
- Division of entrapped membrane (surgery or laser)
What is an upper airway condition seen in horses that is considered the most frequently diagnosed but least understood?
Horses with laryngeal hemiplegia cannot fully dilate what?
What does this produce?
- Larynx on affected side
- Produces an obstruction to airflow
Idiopathic laryngeal hemiplegia refers to what?
Is this referring to partial or complete obstruction?
- Damage to LEFT recurrent laryngeal nerve
- Can be either partial or complete
The majority of left-sided hemiplegias are what?
Can laryngeal hemiplegias also be right-sided?