User:Goshannon
This is a case report, describing severe laryngeal paralysis presenting rapidly in our yellow lab
Bubba, an otherwise healthy 12 year old male yellow Labrador retriever, the progressive worsening with conservative (nonsurgical) management, and his dramatic recovery following medical management specifically addressing a neuropathic etiology.
For over 12 years Bubba remained my very loyal companion, after my wife my best friend, my sailing and fishing buddy, spending many hours flying with me, weather foul or fair, night or day, until WE retired a few years ago to our home in Marathon Florida.
Over the past two or three years Bubba and I enjoyed a DAily swim and 2 or 3 mile walk. around three months ago his exercise tolerance changed. Bubba began to tire out much quicker, requiring a five or 10 minute rest before being ready to go again. With limited mobility, I use an electric scooter, accompanied by a good book and amazing cell phone, these rest stops were not unwelcome.
Frequent rewards of dog biscuits increased Bubba's motivation. While he struggled to keep going, vomiting, retching about a cupful of clear watery mucus ensued, followed by inspiratory stridor or a croaking sound, accompanied by marked shortness of breath and rapid respiration. His chest wall intercostal muscles visibly retracted, sucked inward with each struggled inspiration.
Prepared to do an emergency tracheostomy, we rapidly conveyed Bubba to his veterinarian. His labored breathing spontaneously subsided, and after careful examination the diagnosis of laryngeal paralysis was confirmed.
The options offered being either conservative management or surgical. Opting for the conservative (nonesurgical) program, avoiding exertion, hot temperatures and fast feeding of large chunky food, afforded some relief, but Bubba's exercise tolerance over the ensuing months progressively deteriorated, limiting his walks to less than 100 feet before the recurrence of croaking and dyspnea.
Faced with the ominous reality of surgery, fixing Bubba's paralyzed closed laryngeal folds laterally to open position, our natural born water loving pooch becoming landlocked or destined to drowning, we started AGGRESSIVELY searching for alternatives. In addition to being strongly motivated, My wife being a retired speech and language pathologist, and I retired as a cardiothoracic surgeon, we were both FULLY prepared to study, revisit, research, and take a look at canine laryngeal paralysis from a different perspective.
We learned that Canine laryngeal paralysis is a common acquired problem in middle-aged to older, large and giant breeds of dogs, eg, Labrador Retrievers, Irish Setters, and Great Danes. It is seen less often as a hereditary, congenital disease in Bouvier des Flandres, Leonbergers, Siberian Huskies, Bulldogs, and racing sled dogs.
Diagnosis is based on clinical signs; laryngoscopy under light anesthesia is needed for confirmation. Laryngeal movements are absent or paradoxical with respiration. Very interesting to us where the Electromyography finding, showing positive sharp waves, denervation potentials, and sometimes myotonia. Of greater interest were the frequent pathological findings of Denervation atrophy seen in histologic sections of laryngeal muscles.
This information focused our study to search for a neurological basis. By making careful observations of our excellent and cooperative Bubba; appearing healthy, very alert, eating normally, active, and anxious to play, Bubba clearly demonstrated the following pattern initiated by exertion; presenting itself with a single cough, THEN vomiting clear mucous, followed by the development of upper airway obstruction announced by a croaking sound and respiratory distress.
we coned down our attention to neuro anatomy and physiology, leading us to hyperemesis gravidarum of pregnancy, finally arriving at the not unreasonable hypothesis that canine laryngeal spasm may be neurogenic, reflexely mediated, closing and protecting the airway when the CTZ, or emetic center of the brainstem stimulates vomiting, for whatever reason.
Drugs that that depress the CTZ act directly on the emetic center or CTZ, are found to be more efficacious, used primarily to control motion sickness in people, include Meclizine(BONINE,) WHICH IS WELL TOLERATED IN DOGS, DOSE 4 mg/kg, PO, sid, IS REGULARLY AVAILABLE OVER THE COUNTER,
DRUGS THAT works by blocking H1 receptors in the vestibular apparatus and, to a lesser extent, the CTZ. SUCH AS Diphenhydramine 2-4 mg/kg, PO, tid, (benadryl, an antihistamine), IS ALSO REGULARLY AVAILABLE OVER THE COUNTER, AND WELL TOLERATED IN DOGS.
BUBBA WEIGHS 45 KG.
WE INITIATED THE FOLLOWING EXPERIMENTAL REGIMEN;
1. DIPHYNHYDRAMINE, 50 MG TAB IMBEDED IN A MILKY WAY, PO QAM.
2. Meclizine(BONINE,) 25 MG TAB, IMBEDED IN A MILKY WAY, PO QAM.
3. CLOSE OBSERVATION
RESULTS: IMPROVEMENT CLEARLY EVIDENT BY THIRD DAY, PROGRESSING; BY THE 9TH DAY BUBBA WAS RUNNING , CHASING AFTER HIS LADY FRIEND TERRA, A VIGOURUS MINI SCHNAUZER, AS SHE CHASED CATS AND CRITTERS BIG OR SMALL. CONCLUSION: with humble humility, res ipsa loquitar