Trachea Problems

Coughing due to endotracheal tube irritation

Question: Dr. Richards,

Desiree' had her spay and dental work done the other day. I had planned on taking her home the same day but was told she was too groggy to go home. Instead, the vet took her home to monitor the situation.

Yesterday morning the vet called to update me on her condition. She was well enough to go home. She was eating. And a quick physical exam indicated she was just fine. But I was also cautioned that she was constantly coughing. Aspiration was all but ruled out and they think she has a very irritated trachea.

Aside from near constant coughing which sounds congested, her breathing seems to be a little labored. I was told to watch her appetite and demeanor during the week-end and if deterioration or no improvement of her condition, to bring her back Monday for X-rays.

I have to wonder if this type of problem is uncommon and how many days should one allow before looking for other problems associated with this type of coughing.

She is on Amoxycillin and butrophanol which I understand is both a pain killer and a cough suppressant. But a 1/2 tablet of a 1 mg. dose every 8 hours does not seem to be effective in controlling the coughing.

Tony A.

Answer: Tony-

Coughing due to endotracheal tube irritation is fairly common. In some dogs it can be severe, especially dogs with a pre-existing problem like chronic bronchitis or collapsing trachea. There are a lot of factors involved in producing the coughing, such as how tight a fit the endotracheal tube was, whether the cuff was inflated too much or in some cases if deflation of the cuff prior to removal created an ridge in the cuff the was irritating. The cuff is like a balloon around the tube which is inflated to allow a seal to be formed between the tube and the trachea. They are plastic and can form irritating ridges when deflated. I didn't know that this happened until I attended a seminar in which the speaker showed a few slides from endoscopic views of the trachea after removal of anesthetic cuffs. These are usually minor problems.

In some instances a complication like vomiting during the surgery occurs and there is some laryngeal or tracheal irritation from the contact with the vomitus. There would be a small chance of inhalation pneumonia even with an inflated cuff but usually this is not a problem when a pet is intubated.

There are probably some instances in which the tube contacts an infected surface, like an inflamed tonsil, prior to being passed into the trachea and infections occur that were not present prior to the surgery. I don't think this is a common problem but it is why antibiotics are often dispensed.

The dosage for Torbutrol (Rx) can probably be increased, if necessary, but it would be best to contact your vet about this. If Torbutrol is not effective your vet might be willing to prescribe hydrocodone. We use dextromethorphan sometimes, too. The dosage for small dogs is 5mg every 4 to 6 hours. There is a product called Cough Tabs (tm) for dogs that contains this ingredient.

Mike Richards, DVM 11/11/2001

Collapsed trachea - teeth need cleaning

Question: Dr. Richards.

My dog is a 13 year Shih Tzu who has a collapsed trachea. My vet has not heard of dogs receiving medication for this condition. What can I do to make her life more comfortable? She always seems to have a head cold and runny nose but has no fluid in her lungs and does not run a temperature. Her teeth are dirty and recently when she went in to have her teeth cleaned. Much to our surprise she almost died before she was completely sedated. The vet told me that if it was her dog she never would have my dog sedated unless it was a life or death situation. My dog has been sedated by other vets many times in the past. This vet told me to let her teeth go because the risks of sedation were too great. I cannot clean her teeth because she won't let me get near her mouth and she has breathing problem if I try to restrain her. Thanks..James

Answer: James- Dogs really benefit from having bad gingival problems and loose teeth tended to. It is amazing in some older patients how much difference this makes in their quality of life and longevity. I understand the reluctance to anesthetize her. Surprisingly, having one anesthetic crisis does not mean a dog will ever have another one. We have a number of patients in our practice who had trouble during one anesthetic event who we later anesthetized with no problems. I would recommend finding a practice that uses a well trained veterinary technician or another veterinarian to monitor anesthetic procedures and try to find out what anesthetic protocol caused problems the first time and use a different one. Ideally, you could consider a trip to a veterinary school or large referral center employing a veterinary anesthetist. This is almost the only way to have an anesthetic procedure monitored by a trained anesthetist in veterinary medicine and I am sure that is one of the reasons that the anesthetic death rate is much higher in pets than it is in humans. To be honest, though, I would anesthetize a pet of my own again, even after an anesthetic crisis, to deal with bad teeth. I honestly think it is worth taking some risk to get the benefits of this procedure.

There are a number of veterinary texts that cover the treatment of collapsing tracheal through medical means. There is a somewhat controversial article in the newest "Kirk's Current Veteinary Therapy (XIII)", which discusses this condition in some detail. The authors recommend using diphenoxylate (Lomotil Rx) to treat the collapsing trachea problem but this is a controversial therapy. We have tried it in two patients without much success. We have a lot better luck with cough suppressants and low doses of corticosteroids, usually prednisone.

Please ask your vet to review her textbooks for information on treating the collapsing trachea. Almost everytime I pick up one of the Kirk's volumes I find new information on treating conditions that I had not noticed in the book before because I tend to use the books to look for specific information rather than sitting down and reading the whole book. I suspect most vets do that and therefore miss information on some of the conditions covered in the books, just as I do.

Mike Richards, DVM 2/10/2001

Bronchoscopy to check cough with tracheal collapse

Question: Dr. Richards,

I have written you before regarding my dog, Scout, but here's a quick recap: He is a young (1 to 3 years old) Chihuahua/terrier mix who has been suffering from allergies for the past two months. His symptoms have included face rubbing, paw chewing, general itchiness, sneezing and reverse sneezing, a runny nose, hot spots, and a cough. He has tested negative for heartworm. His bloodwork shows no major infection. He has taken two courses of antibiotics and takes Heartguard Plus, which I understand provides some protection against lungworm, nasal mites, etc.

I recently had chest and tracheal x-rays done out of concern for his worsening cough. Neither my vet nor the radiologist who reviewed the x-rays saw any evidence of tracheal collapse, but they both noted some thickening of the lung tissue indicating mild inflammation. My vet diagnosed him as having chronic or allergic bronchitis and prescribed prednisone, which he has been taking for about a week and a half.

Scout's cough was improving on the prednisone, but this past weekend after I had been rubbing his throat his cough worsened again for a few days. He still coughs when he is excited or stressed and occasionally when he eats or drinks.

My questions are:

1. Am I right to infer from your comments on vetinfo that x-rays cannot always detect tracheal collapse? Is it common for x-rays to miss tracheal collapse? Scout's x-rays were taken on inspiration and expiration. At what point would a bronchoscopy be advisable for Scout?

2. Does bronchitis cause increased tracheal sensitivity? I am especially wondering why Scout's cough increased so dramatically after simply rubbing his throat a few times and why the irritation (if that is what caused it) persisted for several days. I can understand why rubbing his throat might cause him to cough while I was doing it, but not why it would make a difference later in the day.

3. What type of anesthestic is used for bronchoscopy? If Scout is intubated, would they be able to see around the tube?

4. Would you recommend bronchoscopy over a tracheal wash in order to examine the cells of Scout's lungs?

Thank you so much for your input. I am very, very grateful for it.

Amy

Answer: Amy-

It can be hard to detect tracheal collapse with X-rays. I don't have a good idea about how often collapsing trachea fails to show up on X-rays but it is often enough that almost all the veterinary texts warn about the possibility of tracheal collapse even with normal appearing X-rays. It shows up better with fluoroscopy, which is a form of X-ray in which continuous motion is visible and it can usually be ruled in or ruled out with bronchoscopy, which also allows taking culture samples and cytology samples, which can aid in the diagnosis of other airway problems. It is a good idea to consider bronchoscopy even in patients that have had confirmed evidence of tracheal collapse on X-rays, because there are often secondary problems, such as chronic bronchitis or inflammatory airway disease. If the coughing persists, then Scout is a candidate for this examination. It is a little unusual for collapsing trachea to cause problems in a young dog, as it tends to worsen with age and many patients are older when they start to cough or when they develop a persistent cough, but problems can be seen at any age.

Dogs with tracheobronchitis often cough when their trachea is palpated (touched) during an examination. This is also true of dogs with collapsing trachea. Sometimes, it is possible to palpate the weakness in the trachea, when the problem is occurring in the portion of the trachea that can be felt running under the skin of the neck. Both conditions cause intermittent coughing, so this clinical sign is not very helpful in distinguishing between the problems.

Bronchoscopy can be done with most of the anesthetic protocols, including gas anesthesia, and different vets have different approaches to anesthesia. In small dogs, it may not be possible to intubate the patient but it is possible to pass a small catheter for oxygen and anesthetic gas alongside the bronchoscope according the descriptions of this procedure that I can find. There are also several descriptions of using alternate anesthetic agents, such as propofol, to maintain anesthesia during this procedure. I don't have a bronchoscope so I have to rely on what I can find in the literature to relay to you.

Bronchoscopy is definitely a better choice than tracheal wash, if you have a choice. If you don't, due to availability or cost, then tracheal wash procedures can produce diagnostic samples and are a good second choice. Bronchoalveolar lavage is also possible and while it is a more aggressive procedure than tracheal wash, it may also produce a better sample for determining what is happening in the lower airways.

There are risks associated with bronchoscopy, tracheal wash and bronchoalveolar lavage due to the procedures and to anesthesia, so it is good to think about when they are actually necessary. We tend to try to treat for bronchitis once before making the decision to proceed with one of these procedures. If we have good success with antibiotic therapy and it continues to work when we use it, we may not ever reach the point that we feel compelled to do more diagnostic work. On the other hand, if antibiotic therapy doesn't help much and we are not certain that allergic bronchitis or collapsing tracheal problems are present, then we do like to refer our patients for bronchoscopy and we are fortunate enough to have a specialist who does this procedure within an hour of our office.

Hope this helps some.

Mike Richards, DVM 11/27/2000

Hypoplastic trachea or Collapsing trachea in Sheltie

Question: Hi Dr.Mike, Hope you are better. I will share something with you for yourself. Get you some "Natren Mega-dophilus" and some Good "Bifidus" that are always refrigerated. It should help you alot. I take 1 Natures Plus "Bifudus" and "Natren Mega -dophilus" just a little everyday and nothing has helped my Stomach and intestines more. Hope it helps you like it has helped many I know who take it. I also take 2 capsules of Symbiotics New Life Colostrium once a day and it has cleared up my skin so much. It is suppose to help your own immune system. And I have heard alot about it helping Diverticulitis. I do not sell any of these things I only take them because they have helped me so much. So I wanted to Share it with you.......Wishing you the Best, Barbara

Alright my Question for you: We found out our 1 1/2 year old Sheltie today has Narrowing of the Trachea after X-rays or is it called a Collasped Trachea which I believe is the same condition.

The Vet did not recommend any Medication, other than keeping our Sheltie from getting over excited /which seems to make him worse when he gets over excited, as he coughs more and than throws up. She said the coughing was due to the throat narrowing down , and it makes a Dog who has this Condition cough.

Last night was the Worse night he ever had, because of so much Company yesterday. Do any of you know any Medication that helps this Condition or is there Surgery that will help?

I would be forever Grateful if any of you can help us make him more comfortable with any good advice. We do not want him to suffer with this coughing all the rest of his life.

Thank you Barbara

Answer: Barbara-

Thank you for the suggestions for aids to my problems. It is good to hear about things that help other people.

It is possible that your vet believes that your sheltie has a condition referred to as hypoplastic trachea, in which the trachea does not develop its normal diameter as a dog grows. This is a congenital defect that has been reported in several breeds, although I haven't seen anything referring to it in shelties. There isn't much that can be done for patients with this condition, although most of them are reported to do well if they are not stressed, are kept cool in hot weather and do not have secondary problems, such as defective tracheal cilia (the hairs that move mucous along the trachea), laryngeal problems or elongated soft palates.

The other possibility is that collapsing trachea is the problem. In this case, there are medications that can help and surgery is an option. Surgeons like to try to treat collapsing trachea early in the disease, feeling that the surgical success rate is better. However, general practice veterinarians are sometimes reluctant to consider surgery early because when complications occur from surgery they can make the situation worse or even cause the patient to die. This makes the surgical situation a quandary -- try it early because the success rate is better, even though complications still occur, or try to avoid surgery and then utilize it as a last resort option if medical treatment fails? I still lean towards avoiding surgery at this time.

We usually try to eliminate secondary infections, utilizing tracheal wash procedures to try to determine if bacterial infections are present unless the pet owner will allow us to refer their dog for bronchoscopy, which we consider to be a better approach. In a dog as young as yours, I would strongly advocate confirming the diagnosis through bronchoscopy and also obtaining cytology (cell) samples and culture samples through the same procedure. This would allow the most comprehensive plan to be formulated for managing the problem long term and also allow a good exam of the upper airways to be sure there aren't complicating factors affecting the larynx or palate regions.

We start out with antibiotic therapy, if it seems indicated by the work up. Sometimes we can eliminate the coughing for a long time, or at least control it on a periodic basis, using antibiotics. Once this doesn't work anymore, we usually try cough suppressants, most commonly hydrocodone and try to keep the coughing under control in this manner. I am not a big fan of bronchodilators, but some vets like them a lot as an adjunct therapy. Eventually, we usually have to use corticosteroids, usually prednisone, to control the irritation and coughing. I would try to put that off as long as possible, within reason, though. It helps a lot to control weight in dogs with this problem, shooting for just slightly below ideal weight, when possible.

I think that you do need to schedule a recheck with your vet since the cough is worsening. It would help to find out if your vet suspects an underdeveloped trachea or tracheal collapse during that visit.

Good luck with this.

Mike Richards, DVM 11/27/2000

Tracheal Collapse

Tracheal collapse is a condition in which the trachea partially collapses as a dog breathes, leading to tracheal irritation, coughing and sometimes secondary changes in the lungs or upper airways. It is most common in toy breed dogs but can occur in larger breeds at times. It is likely that this condition is partially the result of breeding for small size. It is reported to be most common in Yorkshire terriers, poodles, Chihuahuas, pugs and Pomeranians have been reported to be the breeds most commonly affected by this condition (Slatter's Textbook of Small Animal Surgery) but it is reasonably common in all the toy breeds and several other smaller dog breeds.

The trachea is the airway from the larynx to the main bronchi in the lungs. It looks a lot like a "Shop-Vac" vacuum cleaner hose --- lots of stiff rings with flexible tissue connecting them. The rings are actually more like the letter C with the free ends slightly overlapping and are composed of stiff cartilage when properly formed. For some reason, the rings are not stiff enough in some dogs and they can't hold the trachea open against the negative air pressure created during respiration. The portion of the trachea that is not stiff is sucked into the airway, partially obstructing it and leading to irritation and coughing. This happens on inspiration when the portion of the trachea affected is in the neck region and on expiration if the trachea inside the chest itself is the problem. The irritation is self perpetuating, since coughing and increased respiratory efforts lead to further irritation and worsening of clinical signs. Eventually, damage can occur to the lungs, larynx or even upper airways (nasal passages and soft palate regions). Part of the problem is anatomical, but not all dogs with identifiable tracheal collapse show significant clinical signs, so other factors must be partially responsible. Obesity, irritants, allergies, obesity, concurrent heart failure, bacteria, viruses and obesity can all contribute to the problem, as well. If a pet owner smokes, this is another good reason to quit doing so. Smoking does seem to be a factor in initiating and prolonging symptoms of tracheal collapse. The tracheal lining is ciliated and the cilia move in unison, sweeping a layer of mucous, antibodies and other protective substances constantly towards the larynx. This helps to keep foreign material out of the lungs. Chronic irritation of these tissues may make the overall disease in dogs with tracheal collapse much worse.

Cats can have problems with tracheal collapse but it occurs much less frequently in cats than it does in dogs.

The symptoms of tracheal collapse are coughing, difficulty breathing and tiring easily. The cough is usually very harsh, often sounding like a "goose honk". When this condition first occurs many dog owners truly believe that there must be something caught in their dog's airway due to the severity of the cough. In many cases, dogs with tracheal collapse will also have other airway problems such as stenotic (too narrow) nostrils, soft palate disorders and laryngeal damage. Secondary lung changes can occur with this condition that eventually lead to chronic obstructive pulmonary disorders. If the tracheal collapse is occurring inside the chest the increase in pressure on the circulation can lead to heart enlargement or contribute to heart failure. It is very important to evaluate patients suspected of having tracheal collapse very carefully to find problems that may be contributing to the collapse and problems that may be resulting from the collapse. Most other problems found should be corrected if possible since almost all of them respond to treatment better than the collapsing trachea itself. In some cases control of initiating factors such as stenotic nares (nostrils) may even alleviate the symptoms of collapsing trachea, at least for a while. A honking cough in a small breed dog should make a pet owner or veterinarian highly suspicious of tracheal collapse. The average age of onset is somewhere between six and eight years of age but it can occur at a much younger age or wait to show up until much later in life. It may be possible to feel the collapse of the trachea with the fingers on exam. In some cases the narrowing of the trachea can be caught on an X-ray or by ultrasound exam. The best and most definitive way to diagnose tracheal collapse is with an endoscope, though. As the veterinarian looks into the trachea it is possible to see the collapse and to make an assessment of where it is occurring. In most cases the diagnosis is probably made by relying on the history and perhaps X-rays. This is a pretty reliable way to make the diagnosis since the history (including dog breed) and clinical signs are very suggestive of this problem. However, if endoscopy were available at most veterinary hospitals I'm sure it would be the most common way to confirm the diagnosis. In any case in which response to treatment is questionable or when there are complicating factors such as concurrent heart disease it would be a good idea to ask your vet about referral to a specialist or veterinary hospital where endoscopic diagnosis is possible.

There are medical treatments for collapsing trachea as well as surgical treatments. The consensus of opinion seems to be that collapsing tracheal problems are best treated medically until it becomes obvious that medical treatment alone is not going to work. Medical treatment is aimed at controlling the cough, dilating the airways if possible and controlling the secondary inflammation of the tracheal tissues. Bronchodilators such as theophylline, antihistamines such as terbutaline or hydroxyzine and combination products such as Marax (Rx), which is aminophylline, ephedrine and hydroxyzine are used to try to provide a more patent airway. Corticosteriods such as prednisone are used to control inflammation. Cough suppressants such as dextromethorphan, butorphenol (Torbutrol Rx), and hydrocodone (Hycodan and other, Rx) are the most useful medications in our clinic. Controlling the coughing often will allow resolution of the other problems associated with this condition and slow the self-destructive cycle that occurs with tracheal collapse. It is likely that cough suppressants are under-dosed more frequently than over-dosed in dogs with tracheal collapse. Many pet owners notice the most improvement with prednisone but under-dosing of cough suppressants may be partially responsible for this perception. Estimates of success with medical treatment vary but one study (R. A. S. White and J. M. Williams in the April 1994 Journal of Small Animal Practice) reported a 71% success rate with medical treatment. If medical treatment is unsuccessful after the initial attempts or if it becomes less successful over time, surgery is an option. The reported success rate of surgical treatment also varies widely in the literature but it appears that surgery is successful approximately 70% of the time as well. With surgery there is some chance, perhaps as high as 1 in 5, of the dog being worse post-surgically, though. Laryngeal paralysis may occur due to damage to the nerves during placement of tracheal ring supports and it may be necessary to do a permanent tracheostomy if this occurs. In a recent report in the AVMA Journal, Drs. Bubjack, Boothe and Hobson reported that this was necessary in 10 out of 90 patients treated surgically. They felt that the best surgical results were obtained in dogs with early onset of tracheal collapse when surgery was performed prior to six years of age. It seems to be the consensus among surgeons that tracheal collapse occurring in the neck region is more likely to respond to surgical correction than tracheal collapse occurring inside the chest (thorax). In summary, medical treatment appears to be the best approach if the symptoms can be controlled with prednisone, cough suppressants, antihistamines and bronchodilators, or by any combination of the above medications. If there is a poor initial response to medical therapy or if the response deterioriates over time, then surgical treatment should definitely be considered, especially if the collapse seems to be occurring in the cervical (neck) region of the trachea. Treat any possible initiating causes found on careful exam of the pet and treat any secondary problems that occur after the diagnosis of collapsing trachea. Dogs with this problem should probably be examined at least twice a year to allow early detection of any secondary problems that do occur. Weight loss is often enormously beneficial but can be difficult to achieve in a pet that has limited ability to exercise. While it may be very difficult to enforce a strict diet, the end result could be a much healthier and happier dog.

The best reference for a more detailed understanding of tracheal anatomy, function and disease is probably Slatter's Textbook of Small Animal Surgery, 2nd edition. This is a two volume set and it has detailed explanations of normal anatomy and normal function and how they are changed in disease states for many problems that will respond to surgical correction.

Mike Richards, DVM

Paroxysmal respiration, or reverse sneezing, and collapsing trachea syndrome

Question: Dr. Mike,

Can you tell me if there is a relationship between reverse sneezing and tracheal collapse? Most of the articles I've read say that the causes of reverse sneezing may include allergies, post-nasal drip, viruses, or infections. However, I've come across a few articles that equate reverse sneezing with tracheal collapse or obstruction.

Are the authors confusing the conditions because they both produce a honking-type sound, or is there a correlation? I wrote you recently about my dog's cough (possibly due to tracheal irritation), and now he has begun reverse sneezing once or twice a day. Naturally, I am concerned.

Thank you so much for the time you put into answering our questions. You are appreciated.

Amy (Scout's Mom)

Answer: Amy-

I am certain that the condition referred to as inspiratory paroxysmal respiration, or reverse sneezing, and collapsing trachea syndrome are totally different conditions.

However, I think that the symptoms of these conditions are very similar in some cases, though. Especially in dogs with severe coughing episodes associated with the tracheal collapse, which can look a lot like the extreme inspiratory effort that is typical of reverse sneezing.

There are other reasons for confusion between these conditions. They both occur most commonly in small breed dogs and it is likely that there are a number of dogs who have both conditions. Tracheal collapse can be aggravated by any other condition affecting the respiratory tract, making it possible for a dog with reverse sneezing to develop tracheal collapse symptoms over time.

I think that there are probably a number of causes of reverse sneezing and that many cases occur for no discernible reason. According to the "Textbook of Veterinary Internal Medicine" by Ettinger and Feldman, swallowing stops attacks of reverse sneezing. This source says that reverse sneezing may be controlled by massaging the pharyngeal area or briefly closing the dog's nostrils. Several of my clients have mentioned that their dogs respond to rubbing of the upper neck region, so this advice may be useful. Reverse sneezing is a problem of the pharyngeal region.

Tracheal collapse is a problem that occurs because of improper formation of the tracheal rings. Weakness in the tracheal rings leads to a condition in which the trachea collapses, either during inspiration or expiration, depending on the location of the problem in the trachea. This is highly irritating to the dog and coughing results.

Reverse sneezing tends to start at an early age and to be a persistent problem. Tracheal collapse may cause some symptoms at an early age but in most patients there is a gradual increase in coughing over time and it may reach a point in which there are coughing episodes that last for several minutes and do resemble reverse sneezing. Severe tracheal collapse symptoms are more common in older dogs.

Mike Richards, DVM 10/26/2000

Tracheal irritation from trying to leash train

Question: Dr. Richards,

First of all, I want you know how very much I appreciate VetInfo! It is by far THE best source of pet information I have found on the internet. I was happy to subscribe.

I am beside myself about my Chihuahua mix, Scout, and I hope you can help. Two days ago, I took him for a walk with a choke chain for the first time. We were working on the "heel" command, and though I don't believe I was unusually harsh, I did jerk on his chain many times in order to correct him (with a "pop and release" action). I don't remember him choking, coughing, or making any noises at all during the walk or later that day. However, when I brought out his dinner that night (approximately 9 hours later), he was, as usual, very excited, spinning in circles and jumping, and he began to make a honking noise like a goose. He did it about 4 times in rapid succession and then settled down to eat.

My husband and I took him to an animal clinic that night. The vet pressed up and down his trachea and could not get him to "honk" again, although Scout did cough slightly when he pressed hard. The vet's opinion was that I had irritated his trachea and that a tracheal collapse was unlikely.

The next day, I had Scout on a regular collar and leash on a walk. He went after a bird and pulled very hard against his collar. He then retched once, like a cat trying to cough up a hairball. When we came in, he had a drink and retched once again.

This morning, he may have had a very slight muffled cough a few times, but I am not positive that he wasn't just "wuffing" at someone outside. I took him to our regular vet, who also palpitated his trachea (and listened to his lungs and heart, etc.). Her diagnosis was also tracheal irritation, but she also gave me some Clavamox, because I noticed a little bit of mucus on one of his chew toys on Monday (the day I first used the choke in) and a little bit after he sneezed on me on Tuesday.

Some other information that may or may not be related: About a month ago, we changed his food, and about two weeks ago, we started giving him Metamucil to try to keep his anal glands empty. He was allergic to either the food or the Metamucil, and he began chewing his paws constantly. His fur also began to shed much more than usual. He is now on a plain lamb and rice diet and is doing much better, but last week and this week he has still been somewhat stuffy in his nose.

Scout is about a year old. We have had him for about three months. During that time, he has occasionally (several times per week) coughed as if he was trying to cough up a hairball. These episodes don't seem to occur at any particular time. Scout has been eating and playing just as much as ever. He is not overweight, but just right at 14 pounds. (We believe he is a Chi/Terrier mix.)

I still can't help but be worried that I collapsed his trachea with the choke chain, knowing that 1. Chihuahuas have delicate tracheas and are prone to trachea problems, 2. choke chains can damage airways, and 3. he coughed when he was excited, when he drank water, and when he pulled against the leash.

Am I just being paranoid, or could I have in fact collapsed it? Would you advise x-rays or endoscopy? Do you think we should use a harness from now on?

Also, when Scout was at the vet, he ate a treat that another dog dropped from its mouth. Could he catch something this way? (He is current on all his vaccinations.)

Thank you so much in advance, Amy

Answer: Amy-

It is possible that Scout could have tracheobronchitis, which is a contagious disease that causes coughing. If that is the case, the coughing has probably gotten a lot worse by now. Antibiotics can be helpful if this disease is present.

Tracheal collapse would be a little unusual in a puppy this age, but not out of the question. The tendency to develop this disorder is congenital. It happens because the cartilages that form the trachea are not as strong as they should be. The trachea sort of resembles a vacuum cleaner hose, with a series of stiff rings supporting connecting tissue. In dogs, the rings are actually sort of "C" shaped, with the open ends of the C overlapping slightly. In dogs prone to collapsing trachea, the ends of the rings don't overlap and the tissue of the trachea is not fully supported. Eventually, over time, the tissue weakens enough to cause irritation, as the trachea collapses during respiratory efforts.

It is unlikely that a choke collar will cause this sort of injury but it does seem to exacerbate a tendency towards trachea collapse. I tend to think your vet is right that the symptom is more likely to be from irritation, due to this.

In this situation, I would favor using a halter collar such as the "Gentle Leader" collar, rather than a harness. The halter collar gives you the opportunity to continue to correct Scout for training purposes, without putting pressure on the trachea. Dogs object to these collars when your first put them on so it is a good idea to talk to someone who has used them before or to get your vet to show you how to put it on and adjust it if your vet is familiar with these halters.

X-rays can help to diagnose collapsing trachea problems but I would not be in a hurry to take them, as long as Scout is improving. On the other hand, if he is getting worse, or just not getting better, then it would be more important to try to determine if this was a contributing problem. %3