Coal is 12 years old and long retired from his career as a hunting dog. As a Labrador retriever, he was quite famous in his day for his ability to fetch ducks, especially when it involved swimming. Nowadays, Coal is content to spend his days riding in his truck with his caretaker Dan, watching the almond trees grow and occasionally chasing a ground squirrel or two.
Over the last seven or eight months, Dan reports that Coal is making a lot of noise when he breathes. The condition seems to be worsening and Dan reports that Coal’s respiratory efforts appear to be exaggerated and the noise level has increased. As for Coal’s activity, it does not appear to be appreciably reduced. Dan admits to having all kinds of bad thoughts about what might be causing Coal’s excessively audible breathing and is especially worried about cancer.
There are a finite number of symptoms that occur in a far greater number of diseases. Coal’s case is a perfect example of this fact. His increase in respiratory noise is likely the result of some type of obstruction in air flow into and/or out of his lungs, a long list of possibilities. Dan’s concern about the possibility of some type of cancer is valid in the respect that a mass somewhere along the air path to the lungs is certainly possible. This would include the oral cavity, the throat and the trachea. Hopefully this is not the case.
One distinct possibility that comes to my mind is a disease called laryngeal paralysis. This disease shows a higher incidence in older Labradors, Coal being part of that group. Laryngeal paralysis can be an inherited or an acquired disease; in Coal’s case, it would be the latter. Symptoms can include panting, coughing, change in bark tone, exercise intolerance and noisy breathing. Any combination of these signs result from a decrease in nerve controlled function to the larynx or voice box.
The larynx is a specialized area in the throat that protects the lungs from other than air entry during swallowing while allowing air passage into the lungs. It is also the area in a dog where barking and growling are generated. If there is decreased nerve function to this area, one or more of the mentioned symptoms can result. The list of possible causes of this decreased nerve function is too long to go into here, but in these cases, a thorough evaluation of the patient is necessary. Coal is a case in point.
Coal’s veterinarian will among other things, perform radiographs of Coal’s throat and lungs. Often with laryngeal paralysis, secondary pneumonia can develop because the larynx is not properly protecting the lungs during swallowing. Radiographs can help demonstrate this. Coal will also need a direct throat examination and evaluation of laryngeal function. I like to do this using a light anesthesia and a special scope to visualize laryngeal function during breathing. Cases of laryngeal paralysis will show some degree of decreased motion of the larynx during breathing giving a diagnosis of laryngeal paralysis.
Treatment for this disease depends on the severity of the condition. If there is compromise to quality of life in the form of decreased activity and exercise intolerance, surgery should be considered for this patient. Surgery is designed to permanently open the laryngeal passage and eliminating the restriction caused by the decreased or absent laryngeal function.
Hopefully it is obvious from this discussion that Dan needs to take Coal to his veterinarian. Whatever is causing his loud breathing needs to be identified and hopefully it will be something that can be fixed.