Page 2268 - Cote clinical veterinary advisor dogs and cats 4th

1126 Laryngeal, Pharyngeal, and Oral Examination

• Evaluate palate length, shape, and position ○ Look for puddle sign: pooling purulent
○ Normal length: palate usually slightly exudate at ventral part of larynx or rostral
VetBooks.ir the epiglottis is retracted ventrally by pres- tracheobronchial grass awns and absent
trachea; present in 83% of dogs with
overlaps the apex of the epiglottis; when
in 80% of dogs with bacterial airway
sure with the laryngoscope blade near its
base, the epiglottic tip easily disengages
disease.
from the soft palate. • Evaluate laryngeal function under light
○ Elongated palate: palate extends caudal anesthesia to rule out laryngeal paralysis.
to epiglottis apex, contacting body ○ While assistant holds maxilla up with
of epiglottis when ventral to apex or gauze tie, grasp tongue with gauze sponge
extending beyond its lateral margins, in nondominant hand, and pull base of
contacting arytenoid cartilage when dorsal tongue and epiglottis downward with a
to apex. laryngoscope blade (occasionally blade
○ Palate with oblong extension off caudal must be used on epiglottis itself, which
midline indicates elongated palate being may affect laryngeal function). Alterna-
suctioned into laryngeal ostium during tively, insert an endoscope up and over
inspiration. epiglottis to view larynx without distorting
○ Short palate: extends rostral to midpoint local anatomy.
of tonsillar crypts. ○ If normal movement (abduction synchro-
○ Cleft soft palate: split along midline, down nized with inhalation), paralysis ruled out
one side or both sides ○ If paradoxical movement (arytenoids
○ Nasopharyngeal mass: palate may bulge adduct on inspiration and blow open on
ventrally exhalation), laryngeal paralysis diagnosed;
• Press downward at base of epiglottis with can be unilateral
laryngoscope blade to disengage the epiglottic ○ If no movement or unsure, give doxapram LARYNGEAL, PHARYNGEAL, AND ORAL
apex from its resting position on the soft 1 mg/kg IV, and watch for deep inspira- EXAMINATION The normal laryngeal ostium
palate. Evaluate shape, and position. tory breath about 8 seconds after injection. is diamond shaped with the corniculate processes
○ Normal epiglottis: spade-shaped from On inhalation, cartilages should abduct; if of the arytenoids framing the top, the cuneiform
dorsal view. When disengaged from they move inward (paradoxical), laryngeal processes framing the wider midpoints, and the vocal
caudal border of soft palate, epiglottic paralysis present. If no movement seen, folds (extending ventrally from the caudal surface
lateral margins are oriented horizontally watch for active motion as anesthetic of the arytenoids) framing the ventral half of the
so that the laryngeal cartilages/ostium can wears off. Some dogs with early laryngeal diamond. Abaxial (lateral) to each vocal fold is a recess
be seen without needing to compress the paralysis will have no motion, but vocal (laryngeal ventricle) lined by mucosa known as the
epiglottis with the laryngoscope blade. folds will quiver. laryngeal saccule.
○ Abnormal epiglottic shape: neoplasia,
calcification, swelling/edema
○ Epiglottic retroversion: because of hyoepi-
glotticus muscle weakness, the epiglottis is
rotated dorsocaudally (vertically oriented),
is diamond shaped from a front view,
and covers the laryngeal ostium during
inspiration.
• Examine larynx
○ Normal laryngeal ostium is diamond
shaped with the corniculate processes
(“horns”) of the arytenoids framing the
top, the cuneiform processes (“knees”)
framing the wider midpoints, and the
vocal folds (extending ventrally from
the caudal surface of the arytenoids)
framing the ventral half of the diamond.
Abaxial (lateral) to each vocal fold is a
recess (laryngeal ventricle) lined by mucosa
known as the laryngeal saccule.
○ Abnormal shape caused by neoplasia,
inflammation, congenital cyst, trauma
○ Animals with inspiratory dyspnea may
have swollen mucosa and everted laryngeal
saccules.
○ Animals with laryngeal paralysis have a
visible laryngeal ostium between breaths
but is narrowed on inspiration.
○ In animals with laryngeal collapse, the
saccules are usually everted, and the LARYNGEAL, PHARYNGEAL, AND ORAL
EXAMINATION A palate of normal length usually
corniculate processes may be touching slightly overlaps the apex of the epiglottis; when the LARYNGEAL, PHARYNGEAL, AND ORAL
or overlapping on midline. epiglottis is retracted ventrally by pressure with the EXAMINATION Examination of the nasopharynx
○ Dogs may have laryngeal webbing from laryngoscope blade near its base, the epiglottic tip is performed by retracting the soft palate rostrally with
debarking. easily disengages from the soft palate. a spay hook (shown), stay suture, or Babcock forceps.

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