Laryngeal Paralysis in Dogs
by Roger Ross DVM
Just to orient you in case of slight confusion; the Larynx is also known as the "voice box".
It's located in the throat and connects the mouth and nasal passages with the trachea.
There are muscles attached to the larynx and sometimes these muscles become paralyzed (don't respond to neural signals telling them to contract) which causes difficult breathing.
If you've ever been bumped or karate chopped in the throat just right; that terrible sensation of not being able to inhale normally is caused by temporary paralysis and you'll know what we're talking about.
Except that the type of laryngeal paralysis we're discussing here isn't the type caused by trauma or karate chops.
The type of laryngeal paralysis that we see occasionally in veterinary medicine is caused by a dysfunction of the nerves to the throat.
Specific causes are unclear. It could be caused from damage done by kennel cough germs, excessive barking, choke chains, excessive pulling on the leash, getting stuff stuck in the throat, etc.
But more likely, the cause is related to a neural defect and not related to trauma. We're not really sure.
But here's what we do know:
Most common in large breed dogs of middle or older age.
The exception being when the problem is caused by a congenital defect in young pups of certain breeds: Dalmatians, Huskies, and Bouviers.
Small breed dogs and cats can get laryngeal paralysis too, but it's not as common.
Symptoms:
Common clinical signs include progressively noisier breathing, intolerance to exercise, and sometimes a voice change.
More severe signs include coughing and gagging, vomiting, and sometimes a near inability to breathe.
This can, of course, be lethal and an emergency...especially if the dog panics.
Treatment:
Surgical insertion of an endotracheal tube may be needed...usually under light anesthesia or sedation. Usually oxygen is given. It might surprise you that oxygen in high concentration is very calming and soothing. And gives good pain relief. Thats because the cells in the brain and the rest of the body, for that matter, go crazy if deprived of O2.
Sometimes all you have to do is calm the patient down so they can relax and breathing will improve. In people, this is what's happening in "panic attacks"
Surgery:
There are several types of surgery available for laryngeal paralysis, all of which are designed to increase the size of the opening of the airway to allow easier passage of air.
The surgery most frequently performed is called an arytenoids lateralization. This is also known as a laryngeal tieback.
This surgery involves opening the larynx from the side of the neck to expose the piece of cartilage to which the vocal fold attaches.
Only one vocal fold usually needs to be tied back. Most dogs respond well, although the surgery does not necessarily make the dog act perfectly normal again.
After the surgery, most dogs are sent home for a couple of weeks of rest. Mild coughing is common after the surgery, but should resolve within a week or two. Improved breathing is usually seen almost immediately after surgery and usually lasts for the life of the dog.
Your vet will probably send you home with antibiotics, anti-inflammatories, and possibly some sedatives and/or cough suppressants for a short period.
Might this be a condition (if not an emergency situation) relieved by chiropractic manipulation of the neck (cervical spine)? I don't think so, but then again, I'm not sure.
