In a sudden burst of reckless Khulyesque boldness, yours truly has decided to tackle the touchy topic of pets who suffer from three chronic and frustrating diseases: megacolon, otitis and laryngeal paralysis.
These diseases seemingly don’t have much in common except that we frequently see patients who have endured months to years of obstipation, chronic ear pain or suffocation without much help from medical treatment. Let’s review the facts.
Idiopathic megacolon in a 10-year-old cat.
Feline idiopathic megacolon is a progressive condition that invariably leads to irreversible distension of the colon. Two-thirds of the time, we don’t know the cause of megacolon in cats, so it can be called an idiopathic functional obstruction. In some cases, the megacolon is secondary to pelvic fractures or, especially in dogs, to a tumor, i.e. a mechanical obstruction.
Feces in a megacolon are rock hard and cannot conceivably go through a poor cat’s anus. Recall that one of the colon’s main functions is to reabsorb water. We can give all the cisapride, lactulose, high fiber supplements and special diets in the world, but that poop is just not coming out. It’s mechanical. Interestingly, the chapter on the large intestine in Slatter’s Textbook of Small Animal Surgery reads: “Studies documenting stimulation of in vivo colonic propulsive motility in cats are lacking.”
End-stage otitis externa in a 9-year-old cocker.
And then, there’s the dreadful enema. At best, it will help temporarily. At worst, it can cause traumatic rupture of the colon. Either way, the smells and sights probably will make your toughest technicians sick to their stomachs. An enema doesn’t achieve much once the colonic distension has reached the point of no return.
After awhile, these cats end up in pain, dehydrated and anorexic, which makes them poorer anesthesia candidates than if surgery had been recommended earlier. Surgery includes a thorough laparotomy, followed by resection and anastomosis of most of the colon. It is not unusual to remove a colon that is the size of your forearm.
The main secret of subtotal colectomy is to avoid tension along the suture line. Occasionally the only way to achieve this is to sacrifice the ileo-colic valve. This, however, may lead to a looser stool and secondarily to small intestinal bacterial overgrowth (SIBO).
Sure, complications do occur, such as chronic diarrhea and septic peritonitis, but in the vast majority of cases megacolon is curable through surgery.
Otitis externa and media, most commonly seen in cockers, is a progressive condition that may lead to irreversibly thickened, infected and painful ear canals. With end-stage otitis, the ear canal is so stenotic that flushes and medications cannot reach the site of the infection, which means the treatments are ineffective.
Once the tympanic membrane is ruptured (in at least 75 percent of the cases), otitis externa leads to otitis media by extension. A vicious cycle may very well start in which the infected bulla exacerbates the infected canal and vice versa.
Calcification of the canal is often a sign of irreversible damage. If you palpate calcified ear canals and can’t fit the cone of your otoscope in the canal, then your patient has irreversible ear changes. At that point a complete cure is impossible through medical management.
After awhile, these poor pets end up in constant pain, sometimes with self-trauma, a head tilt and other vestibular signs. Chronically painful cockers may become head shy and aggressive, which is often unfairly blamed on the breed. And then there’s the unmistakable smell, which has strange physical properties. It can invade every room of a clinic within 30 seconds while leaving many pet owners completely indifferent.
When dealing with end-stage otitis externa and media, the most appropriate surgical procedure is a combined total ear canal ablation (or TECA) and a lateral bulla ostectomy. The most important secret of this surgery is to know the indications of a TECA.
If the horizontal canal is affected, a lateral wall resection (Zepp procedure) or a vertical canal ablation likely will fail. It is probably fair to say that they are contra-indicated with end-stage disease.
In other words, the goal of surgery is to get rid of the disease entirely. The “bulla” procedure allows removing debris and hair as well as submitting a culture of the pus invariably found there. Excising the entire ear canal means the entire disease is physically removed.
Sure, complications occur, such as loss of the palpebral reflex and a head tilt, but in the vast majority of cases otitis externa and media are curable with surgery.
Laryngeal paralysis is a progressive condition that invariably leads to dyspnea and suffocation, most often in older Labradors. One way to describe how laryngeal paralysis patients feel is to imagine yourself breathing through a straw. It’s stressful when you are resting but unsustainable when you need to move around.
Life is tough without enough oxygen. After awhile, these dogs end up hyperthermic and exercise intolerant. Bilateral laryngeal paralysis doesn’t come and go; it’s there to stay, and all the acepromazine and steroids in the world won’t help long term.
Most surgeons prefer the crico-arytenoid tie-back technique, which is performed through an approach on the side of the neck along the larynx. The surgery entails placing sutures between the cricoid and the arytenoid cartilages on only one side of the larynx. Bilateral surgery drastically increases the risk of aspiration.
Sure, complications such as aspiration pneumonia do occur, but in the vast majority of cases laryngeal paralysis patients can be helped significantly with surgery.
Obstipation, chronic ear pain and suffocation severely decrease our patients’ quality of life. Medical management of these end-stage conditions is unrewarding at best. Let’s keep in mind that we can make a tremendous difference in the lives of these patients by recommending surgery early in the disease process.
Phil Zeltzman is a mobile small-animal surgeon in Allentown, Pa. His website is DrPhilZeltzman.com.