Transcript Laryngeal Paralysis - Veterinary Specialists of South Florida

Veterinary Specialists of South Florida
Presents...
Laryngeal Paralysis
JENNIFER REAGAN, DVM
Chelsea – 12yo FS Australian Shepard
 History


Labored breathing, stridor
and cough
Increased panting and
respiratory effort for the
last year




Progressive last 4 months
Bark change
Exercise and heat
intolerance
Renal Insufficiency
 PE


Vitals WNL
Increased BV sounds



No crackles or wheezes
Stridor
Quadriceps atrophy
bilaterally
Differential Diagnosis
 Stridor
 Upper airway obstruction
Laryngeal Paralysis
 Masses
 Laryngeal or tracheal collapse
 Trauma
 FB
 Brachycephalic syndrome

Diagnostics
Anatomy
of the
Larynx
Innervation of the Larynx
Etiology of Laryngeal Paralysis
 Congenital
 Bouvier des Flandres, bull terrier, Siberian husky, Dalamtian,
Rottweiler and white coated German shepard breeds.
Degeneration of the nucleus ambiguus (bouvier des Flandres)
 Polyneuropathy (Dalmations)

 Acquired
 Idiopathic
 Disease


Myasthenia gravis, hypothyroidism, polyneuropathy, lead or OP
toxicity, retropharyngeal infection, myopathy, neoplasia.
Trauma

Iatrogenic – thyrodectomy and tracheal collapse
Signalment
 Large breed > Small breed
 Male > Female
 Acquired idiopathic most common
 Labrador, Afghan hounds, Irish Setters
 Middle aged to older
Clinical Presentation
 Common CS
 Voice changes
 Coughing and gaging
 Exercise intolerance
 Stridor
 Collapse or acute dyspnea
 Slow progression (months → years)
 Can present as an emergency
Emergency Presentation
 Oxygen
 Cooling
 Sedation
 Opiods – dog
 ACE, Valium – cats
 Steroids
 Dex SP – 1 mg/kg
 Prednisone – 5-10 mg/kg
 Intubation/ventilation
 Tracheostomy
Diagnostics
 R/O other causes of upper airway obstruction
 Cervical /thoracic radiographs
 Laryngeal exam
 Safe for anesthetic and surgical candidate
 Thoracic radiographs
Aspiration pneumonia
 Megaesophagus



Esophagram radiography/fluoroscopy
Minimal database - CBC/Chem/UA
Laryngeal Exam
 Light plain of anesthesia
 Thiopental
 Propofol
 Too sedate = false paralysis
 LarPar
 Paramedian position
 Paradoxical movement
 Assistant necessary
 Doxapram (1mg/kg)
 Methods:
 Echolaryngography
 Transnasal laryngoscopy
 Laryngoscopy per os
Additional Diagnostics
 Acetocholine– receptor AB test
 Laryngeal paralysis can be the only sign of myasthenia gravis
 Thyroid panel
 Electromyography nerve conduction velocity test
 Muscle biopsies
Treatment Options - Medical
 Who’s a good candidate?
 Mild disease
 Megaesophagus / esophagus dysfunction
 Small breeds usually more successful
 Warn owner disease is progressive
 Medical Management
 Exercise restrictions
 Weight control
 Avoid heat, stress and humidity
Treatment Options - Surgical
 Unilateral Arytenoid Lateralization
 Other techniques:
 Vocal Fold excision – scar formation


Partial Arytenoidectomy


20% glotic stenosis, 50% complications
< 50% serious complications (death)
Bilateral Arytenoid Lateralization

Majority get aspiration pneumonia
Unilateral Arytenoid Lateralization – AKA “Tie-back”
Goals and Complications of “Tie-back” Surgery
 Goal:

To open the rima enough
to decrease airflow
resistance without
excessive risk of aspiration
 Complications:



Aspiration pneumonia
Repair failure
Post-op seroma
Sedation
 Cold/warm compress

Prognosis “Tie-back”
 Overall Good!
 28% chance of complications
 18-19% aspiration pneumonia
 5% acute respiratory distress
 4% repair failure
 72%-90% less respiratory distress and improved
exercise tolerance
Increased Complication Rate
 Risk Factors:
 Pre-existing aspiration pneumonia
 Progressive neurological disease
 Esophageal disease


Post-op megaesophagus
Temporary Tracheostomy
50% developed complications
 Of those 62% died

Chelsea’s Outcome
 Complications:
 Aspiration Pneumonia
 Renal Failure
 Improved Respiratory Function:
 Less effort
 Less exercise intolerance
References

Burbidge HM. A review of laryngeal paralysis in dogs. Br Vet J. 1995; 151: 71-82

Evans, Howard E.. Miller's Anatomy of the Dog, 3rd Edition. W.B. Saunders Company, 1993. 8.3.1).

Fossum, Theresa Welch. Small Animal Surgery, 3rd Edition. C.V. Mosby, 2007. 28.1.5).

MacPhail, CM, Monnet, E: Outcome of the postoperative complications in dogs undergoing surgical
treatment of laryngeal paralysis: 140 cases (1985-1998). J Am Vet Med Assoc. 2001; 218(12): 1949-56.

Radlinsky MG., Williams J., Frank PM., Cooper TC. Comparison of 3 clinical techniques for the
diagnosis of laryngeal paralyses in dogs. 2009;38:434-438.

Shelton DG. Acquired Laryngeal Paralysis in Dogs: Evidence Accumulating for a Generalized
Neuromuscular Disease. Vet Surg 2010; 39:137-138

Stanley BJ., Hauptman JG., Fritz MC., Rosenstein DS. Kinns J., Esophageal dysfunction in dogs with
idiopathic laryngeal paralysis: a controlled cohort study. Vet Surg. 2010 39:139-149.
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