What should the owner be told with animals wihtt tracheostomy?
At risk for inhaling things - no running through fields, swimming, be careful when bathing.
How many cartilages make up the larynx?
What are the 5 cartilages of the larynx?
Epiglottis Cricoid = most caudal Thyroid - most lateral and paired Arytenoids - also paired, and burried under thyroid
What is the important muscle of the larynx? What is it's important function? What innervates it? What do diseases that interfere with innervation of CAD do?
Cricoarytenoideus dorsalis Opens arytenoids when inspire Innervated by caudal laryngeal nerve - terminal segment off recurrent laryngeal nerve Dz - prevents effective dilation of glottis
What innervates the cricoarytenoideus dorsalis?
Caudal laryngeal nerve (terminal segment of recurrent laryngeal nerve)
What can cause laryngeal paralysis?
Idiopathic degeneration = most common Congenital Trauma/iatrogenic Neoplasia
Idiopathic degeneration leading to Lar Par is a sign of?
Generalized Polyneuropathy can also be geriatric onset laryngeal paralysis polyneuropathy GOLPP
What breeds are at risk for lar par?
Bouvier, Husky, dalmation
Dogs with idopathic paralyisis start showing signs when? Which breeds?
Mid-late stage of life Labs, Afghans, Irish Setters, Goldens, Irish Wolfhounds
What are C/S of idiopathic paralysis?
-inspiratory stridor -decreased exercise tolerance -cyanosis & collapse -change in bark -gagging -coughing -generalized polyneuropathy -esophageal dysfunction (consider esophagram) often worse in summer
DX idiopathic paralysis
Ascult larynx Thoracic rads on aspiration Visual inspection under Light GA IV thiopental best choice, no longer available - propofol can also be used, but be careful depth of anesthesia (goes quick, but be careful, too deep = stop breathing)
When watching for lar par have somone else call out when the dog is breathing out and in and you should see?
when brething in - arytenoids should pull apart and open the airway w/every inhalation
Dx of lar par is made based on? Unilateral a problem? What drugs may help?
Failure of arytenoids & vocal folds to abduct during inspration Almost always both sides affected to see c/s Doxapram - stim resp center to breathe - increase intrinsic laryngeal motion = aid DX
Surgery for lar par
Arytenoid lateralization - permanently pull one out of the way. Anchor arytenoid in abducted position =rima permantly dialted Usu unilateral on L side (surgeons R handed, also shown in books)
For arytenoid lateralization Dog in what position? Neck in what position? Incise where?
Dog: right lateral recumbancy Neck: extended & supported on sand bag Incise over larynx just below jugular vein bifurcation.
Wat muscle is incised for arytenoid lateralization? What is retracted? Then transect what? (2x) Disarticulat what? And finally?
Incise thyropharyngeous Retrract wing of thyroid cartilage Transect cricothryoid articulation Transect CAD musccle Disarticulate cricoarytenoid Tie arytenoid (muscular process) to cricoid or thyroid.
Complications of artyenoic lateralizatoin?
Fragmentation of arytenoid Failure to adequately open rima glottidis Suture failure post op - place 2 non-absorb = prolene Seroma or perilaryngeal edema (not usu imp) Aspiration pneumonia (20-30% rest of lives) Progressive polyneuropathy