VetInfo Digest       July 2002

This Month:

The 80/20 and 10/80/10 Rules

Puppies, Kittens and Special Diets

Laser Surgery - Is it Necessary?

Cytauxzoonosis felis

Tick Control in Dogs and Cats

Does it Pay to Use Online Pharmacies?

 

This Month's Note:

Many of you asked about my recovery from the cat bite that I discussed in last month's VetInfo. I am very happy to report that my hand is almost 100% normal at this time. I added a very deep talon strike from a bald eagle to the same arm's list of scars this month. My receptionist, Susan, is threatening to put together a coffee table book consisting of pictures of various animal bites on my arms and hands. She wants to call it "Bites of Mike". If anyone is interested in a copy, let me know!

For the few of you whose dogs suffer from perianal fistulas, a topical ointment, tacrolimus (Protopic 0.1% tm) applied twice a day may be helpful. At this time, perianal fistula formation, most common in German shepherds, is considered to be a medical condition rather than a surgical condition, by most veterinary dermatologists. This is a big change in thinking!

If you miss a dose of the monthly heartworm prevention medications it is better to give a dose as soon as you realize the omission and then to go back to a monthly schedule based on the date that the this pill is administered. Don't put it off waiting for a heartworm check! The new injectable heartworm medication ProheartÔ has a 30 day "reachback" period, so missing the six month injection date by up to 30 days will still be safe, but it is best not to push the limits.

 

The 80/20 Rules

Financial advisors to veterinarians frequently point out to veterinarians that about 20% of their clients provide 80% of the practice profit. These are clients who take good care of their pets, seek advanced care when it is necessary and pay their bills. It is pretty likely that most of the subscribers to the VetInfo Digest fall into this category. Veterinarians will usually work hard to keep these clients. In our practice it is possible to get into the top 20% by spending about $275 per year on pet care. This figure probably varies widely and is undoubtedly higher in urban areas. Keep in mind that you most likely are a very valuable to your veterinarian's practice but use this leverage only when it is really necessary.

Veterinarians tend to use this same rule in a slightly different manner. Many veterinarians believe that 80% of their daily hassles are caused by 20% of their clients. Fortunately, most of the clients who take good care of their pets and who pay their bills don't fall into this category. Unfortunately, some do. We have two or three clients who are really very dedicated pet owners and who are going to do what is best for their pets in almost all cases, but who complain frequently about having to do so. Veterinarians really do take this type of complaining to heart. We have a couple of clients who demand attention immediately because they are aware of the fact that they are among our top clients from a financial aspect. We don't mind giving extra attention to clients who support us well but we can't always do this. Sometimes emergencies or just busy days stop us from being able to provide instant gratification to clients who seem to need it. If you do provide strong financial support for a practice you do deserve some consideration for it, just don't negate that good by also becoming one of top 20% of stress producers as well!

It is generally accepted that 80% of our patients are going to get over their present problems no matter what we do, as long as it isn't something that makes them worse. This means that doing absolutely nothing would still result in a pretty good success rate for most veterinarians and giving almost any therapy will ultimately be successful as long as the client can be convinced to wait for the pet to get over the problem itself. We can help many of these patients get better more quickly if a good diagnosis and treatment plan are developed. This can help distinguish a really good vet from a less competent one but when you think about it, most people are going to have a hard time distinguishing the true quality of veterinary care their pet receives when the odds are in favor of recovery even with lower quality care.

Another variation of the 80/20 rule is that 80% of what I do every day is routine and I only have to really think hard about a patient's condition 20% of the time. Some veterinarians seem to have decided that there is enough income potential in the 80% of the cases and appear to have given up on thinking and thus the need to keep up with medical and surgical advances. It is sad that this occurs but it does. There are some telltale signs of vets of who have given up. Some refuse to refer patients to specialists. Others are quick to refer problem patients away when possible but won't attempt to provide any sort of compromise care if the trip a specialist isn't possible for the pet owner. Vaccination for everything a vaccine exists for is a pretty good sign that a vet is attempting to live off the routine care without putting out the additional 20% effort needed for really good care. If you leave the exam room with a diagnosis of your pet's condition every time the odds are that your vet isn't extremely brilliant -- the odds are that he or she is avoiding telling you that more work is necessary in some cases to find a diagnosis and hoping that the odds will work in their favor.

There is a corollary to the 80/20 rule I think of as the 10/80/10 rule. This is based on research that my father did when writing war games. He and his colleagues used a sliding scale to assess risk taking behavior. They estimated that 10% of people will always take risks, regardless of the situation they are in. Another 10% of the population will never take risks, no matter how much they might have to gain by doing so. The middle 80%, in which most of use function, regulate their risk taking in proportion to their estimation of their current situation. If they are in a "winning" situation they tend to be more conservative about taking risks and if they are in a "losing" situation they tend to take larger risks or at least to take some risk more readily.

If you think carefully about how you make decisions you might be able to figure out which of these groups you belong to. As an example from my practice experience, many people fear the use of anesthesia. There is good reason to have this fear because some pets die when anesthetized. However, there are also very good reasons to use anesthesia and most people are capable of recognizing the need for anesthesia and will consent to it under appropriate circumstances.

The 10% of my clients who can't take any anesthetic risk have made some horrendous choices in order to avoid anesthesia. I have a patient who has such severe periodontal disease that there is exposed bone visible for several millimeters around the base of his teeth. He obviously is uncomfortable. But his owner will not allow me to attend to this problem because it will require the use of anesthesia. This dog is miserable because his owner can't accept any risk. I have even had clients refuse to allow us to repair bone fractures unless I could do surgery without anesthesia. In one of the worst cases of anesthesia fear that I can remember, a client refused to allow us to remove an object that their dog had ingested and instead just hoped it would pass, resulting in the dog's death. These are extreme examples but if you know that you have an unreasonable fear of anesthesia, or any other medical procedure, it might be best to have a designated risk taker to help you with decision making -- someone you know to be reasonable and who has the best interests of your pet at heart.

I also have clients who request that I anesthetize their dog for reasons that I consider to be unjustified. We have had several clients ask us to anesthetize (not sedate) their pets for car travel. Again, this is not made up. I have actually had clients ask us if it was OK to stop by on their way out of town on vacation so that we could "Give him something that will make him sleep for 4 or 5 hours, not just make him woozy like last time." This just isn't a reasonable use of anesthesia. These are clients who either aren't aware that there is a risk or who just take risks on a routine basis without thinking about them.

We do sometimes use general anesthesia to make it possible to do procedures like nail trimming or removing severe matting when a pet simply won't allow the procedure without endangering itself or everyone else in the room without it. I think of this as falling in the middle 80% -- it is something we do when we know that someone will get hurt (so we're going to lose) unless we take the risk.

Often, the best way to make sure that you are thinking clearly about risk taking is to ask yourself what sort of risk you are taking if you do something -- and also what sort of risk you are taking if you don't. As long as you don't have an outright phobia about the risk you are considering this will usually help to clear the thought process. Whether or not to pursue heartworm treatment for a pet with heartworms helps to illustrate this point.

In a dog, heartworm treatment is relatively safe. Approximately 1 to 3% of dogs treated with melarsomine, the newest of the adulticide heartworm medications, will die during the six to eight weeks following administration of the medication. During this time period most dogs who have heartworms will not die as a result of the heartworm infestation. It is likely that the odds of death in the next few weeks for most dogs affected by heartworm disease is less than 0.1%. On the other hand, the majority of dogs with heartworm disease will eventually die from the disease and they will have significant disability from the disease prior to death. For illustration sake, let's assume that 75% of dogs who develop heartworm disease will eventually die from the disease. Given this situation, the short term increase in risk is obviously a minor concern compared to the long term risk. The exception to this rule are a few people who will never be able to accept having made a decision that caused their dog to die prematurely (other than the bad decision not to be using heartworm medications). This small group of clients sees the risk in a whole different light. For them, the thought of taking any immediate risk or responsibility for their pet's death is just overwhelming. Once in a while I can get the point about long term risk versus short term risk across to a client like this.

In a cat, heartworm treatment is decidedly unsafe. When heartworm treatment is attempted in cats a little more than 50% of the cats die within the few days to weeks after adulticidal heartworm therapy is initiated. In contrast to this, slightly less than 50% of cats will die from the effects of heartworm disease if it is not treated. Cats can be uncomfortable due to the effects of heartworm, so there is some disability to consider. For most people this discomfort is not enough to justify the risk of treatment. The decision making in cats is obviously much easier and in most cases our clients are content with not pursuing therapy. Even in this situation we have had a couple of clients who wished to go ahead with therapy. Since I tend to expect around 10% of my clients to be extreme risk takers, this is not too surprising to me.

Knowing yourself can be really helpful when you actually have to make a decision in a hurry. You might be able to say to your vet "I know that I am more willing than most people to take risks. If there is the potential for a cure despite high risk, I'm willing to accept the odds and move on". If you know that you are a low risk taker, you might have to explain to your vet that you just can't bear the thought of making a decision that causes your pet short term harm and ask that another family member be consulted if the decision appears as if it will be hard to make. For the larger group that has to make decisions based on an assessment of the situation and a thorough understanding of the risks, it is important to know both the expected benefits and the potential risks of medical and surgical procedures. Asking questions like "What might happen if I don't pursue treatment" or "are there side effects to this therapy that I should be concerned about" can make the decision making easier. Once in a while I realize that I have forgotten to tell a client about a possible complication that is significant in the decision making and I'm grateful that the client remembered to ask me if there were possible complications --- so don't hold back on these types of questions.

The final part of the 80/20 and 10/80/10 rules to think about is how your vet fits into the picture. If your vet is constantly steering you away from surgical procedures, dental procedures or any event requiring anesthesia it is likely that he or she is a naturally risk aversive. The worst case of this I ever personally dealt with also involved heartworm disease. A new client came to the practice because another veterinarian had advised her that her dog was too severely affected by heartworm disease to treat for the disease. I was perplexed by this because the dog was only three years old, was showing no discernible clinical signs in my office and didn't seem to have a heart murmur or other problem that might indicate that the heartworm disease was advanced. A blood chemistry screen and complete blood count were normal. So I called the vet and asked why he felt that heartworm treatment was too risky. The answer, as closely as I can remember it was, "If I tell a client to treat their dog for heartworms and it dies, then it is my fault. If I tell them not to treat the dog for heartworms because it is too far advanced, when the dog dies it is their fault." To be honest, I don't agree with the logic and I definitely didn't agree that the best interests of the patient would be served by this approach.

My staff sometimes accuses me of being too aggressive, or perhaps too optimistic. I will try "last ditch" surgeries and medical therapies that have very little chance of working as long as I think that my client really understands the poor prognosis, I believe I can adequately control any pain associated with the procedure and there is a chance of at least some improvement, even if a cure is not likely. Once in a while this comes back to haunt me when one of these efforts goes badly and the patient's life is shortened instead of extended. At these times I often find myself using phrases like "When will I ever learn to give up?" I really hope that my clients are not thinking, "Why did I let him do that to my pet?" Fortunately, most of my clients have known me long enough to realize I am more likely to be aggressive than passive and they are aware they can tell me "NO" without hurting my feelings.

I believe that most vets understand that their clients have to make decisions based on their own comfort level. Veterinarians usually try to reach an understanding of what that level is. However it probably does help some to think about how closely your 10/80/10 profile fits that of your vet. It is likely that you will find the care that matches your needs more frequently from a vet who thinks about the risks involved in veterinary medicine in a similar manner to the way you think about them. Watch your vet's decision making and think a little about how closely it matches yours.

 

Puppies, Kittens and Special Diets

Puppies and kittens have different dietary needs than adult dogs and cats. This is not much of a problem for normal healthy puppies and kittens. A good quality kitten or puppy food will meet their needs. Large breed puppies might need a little more specialized formula, but you can buy it for them. The real problem with kittens and puppies comes when they have special medical needs and the only choices available are diets made for adult dogs.

Persistent diarrhea is a fairly common problem in kittens. It seems to be helpful in some cases to feed low fat diets, such as Hill's w/d or r/d (tm) diets. These diets are not meant for kittens and long term use is probably not appropriate, but feeding exclusively these diets for a few days and then gradually mixing in a kitten food will sometimes help in resolving long term diarrhea in kittens. I'm not sure why. Alternatively, limited protein (one protein source) diets meant for ruling out food allergies can be helpful. There are a number of these diets on the market. None that I know of are approved for use in kittens. They are probably safe for short term use to establish if a problem is present but if long term use does seem necessary it would be best to call the company, or ask your vet to call the company, to get help in modifying the diet to make it appropriate for a kitten.

Food allergies can occur in both kittens and puppies. Most of the commercial diets made for food allergies do not claim to be acceptable for use in kittens and puppies. Once in a while we see puppies with food allergies that are causing severe ear inflammation and/or inflammation between the toes or other skin disease when they are as young as 8 to 12 weeks of age. The only commercial diet that I know of that carries an AAFCO (American Association of Feed Control Officials, the regulating body for pet foods) label claim for use during growth is Purina's LA (tm) diet. We have used other diets successfully in the past after consulting with the companies making the diets to get their recommendations for ensuring the health of the puppies. So far this has worked without causing problems we could discern, but it is still important to recognize the need to pay attention to things like poor growth or an unthrifty look. An alternative for puppies is to feed a hypoallergenic or novel protein diet made for adult cats. The dietary requirements for adult cats usually meet those of puppies -- although it is best to ask your vet and/or the pet food company for their advice on this approach, as well.

In our practice we sometimes use low protein diets made for kidney failure patients in growing puppies or kittens. Almost without fail, this is a very hard thing to convince a client to try. The idea of feeding a protein restricted diet to a kitten or puppy seems like lunacy to the client at first. However, we use these diets in young animals most commonly for liver diseases that are causing problems or when we have been able to identify a kidney problem requiring protein restriction. This is a dietary recommendation that definitely isn't found on the bag of food. It may be helpful to remember that the amount of protein that must be ingested is very dependent on the biologic value of the protein. Very good quality protein diets can be very low in protein and still meet the needs of a growing pet. So the use of a diet like k/d (tm) or NF (tm), may be justified even though it seems wrong to use a low protein diet for a growing pet.

I believe that it is almost always inappropriate to use urine acidifying diets, including the grocery store brands such as Purina's "Special Care tm" or Alpo's "Urinary Formula tm" and veterinary diets like c/d (tm) and UR (tm), in growing puppies and kittens. When diets that acidify the urine are used they have a tendency to alter the calcium balance in the body and this is potentially a serious adverse effect in a kitten or a puppy. In all honesty, I have recommended these diets in a few select situations when I felt that there really wasn't much choice, including a couple of male cats who developed urinary blockages at very young ages and a cocker spaniel puppy who developed bladder stones twice by the time she was seven months old. These are unusual cases, though. It is usually better to be cautious about the use of these types of diets in young animals and to avoid their use if possible.

When your vet "prescribes" a diet for your kitten, puppy, dog or cat, be sure to read the bag very carefully. If the diet is not approved for the life stage that your pet is currently in, call the 800 number on the bag, or find the company on the Internet and ask the technical support staff to help you determine if it is safe for your pet and if additional supplementation is necessary -- or if additional supplementation might be harmful. In some cases it is better to get your vet to call the company for you and it is reasonable to ask your vet to do this if the AAFCO statement clearly indicates that the diet is not meant for your pet's condition or your pet's stage of life and your vet has suggested using the diet, anyway.

 

Laser surgery -- Is it Necessary?

There is currently a lot of advertising by veterinarians about the use of lasers in their practices. Before you pay extra for the use of a laser during a surgical procedure, you might want to stop and think about the necessity and advisability of doing this.

Most of the veterinary advertising appears to be drawn directly from the laser company's advertising. There are usually claims that laser surgery is less painful, causes less swelling and controls bleeding during surgery. It is hard to be sure if the claims concerning pain and swelling are actually true, but the importance of this difference is questionable, even if they are true. Control of hemorrhage from small vessels does occur during laser procedures. If a larger blood vessel is accidentally cut with the laser, or is in the way of the incision, bleeding will not be controlled by the laser alone. It is not uncommon for veterinary hospitals that have laser surgical instruments to have a $50 (or similar figure) charge for the use of the laser during surgery. Clients are usually advised of the benefits of laser surgery and asked if they want to have the surgery done using the laser. Many clients, hearing of the potential benefits, opt to pay this fee.

Lasers present some dangers that have to be considered, as well. The laser beam has to be controlled or it will cut tissues that are not meant to be incised. The patient's eyes and the eyes of the veterinary staff must be protected during surgery from inadvertent laser strike. Surgeons inexperienced in the use of the laser may choose inappropriate settings for the laser or may not use it efficiently, resulting in tissue burning around the edges of the incision (char). The smoke created by tissue vaporization must be evacuated as it can be toxic. This is especially important when lasers are used for intra oral or laryngeal surgery, as the patient can inhale the smoke prior to the time it can be evacuated when working in these areas, unless precautions are taken to prevent this from happening.

It is hard for me to believe that using a laser to make a routine skin incision for a surgery such as a spay in order to obtain pain relief really makes a significant difference. The skin incision itself is not the painful portion of the procedure. It is the incision into the muscle and then the suturing of the muscle that causes the pain over the first few days after surgery. Even though the incision into the muscle can be made with the laser, it is still necessary to place sutures. It is not advisable to use the laser inside the abdomen so the pain relief and hemorrhage control advantages do not apply to the incisions necessary to remove the uterus and ovaries during a spay. Is it really worth $50 or more to avoid an incision with a scalpel? I've had lots of skin lacerations and several surgical incisions and I'm certain I wouldn't pay extra to have a laser incision for most surgeries. Like most things, there are probably some vets who would readily make this choice and feel justified in doing so for their patients.

Declawing of cats does appear to be less painful when a laser is used to remove the claws and control of hemorrhage during this procedure does make it possible not to use bandaging, which is a significant advantage. At the present time, I think that this is one of the better uses for laser surgery in veterinary medicine. There is some evidence that the pain control advantage is short lived, so do not hold back on pain relief medications if they appear to be necessary following a declaw procedure, even if it was done using a laser.

There are some surgeries that are easier to do with a laser than with conventional surgical techniques. Removal of tumors from the ear canal is facilitated by the use of a laser, since it is possible to direct the laser beam through the operating channel of an otoscope or endoscope, which is much more difficult, and in some cases impossible, using conventional scalpels. These tumors can also frequently be removed using a radiosurgical instrument (electrosurgical), though.

It is hard for a veterinary client to decide when the use of a laser is actually a major benefit to their pet and when it is not. I would avoid being among the first clients in your veterinarian's practice to authorize the use of the laser procedure. I think that I'd want to know that the procedure had been done by the surgeon, using the laser, at least ten times and more would be better. I would not be willing to pay an additional fee for the use of a laser for a surgery in which an incision in normal skin is being made and the use of the laser is predominantly to make the skin incision. At this time, I just don't think that the pain relief afforded by the use of the laser to make skin incisions is significant enough to matter to the pet. Declaw procedures, removal of skin, ear or oral tumors and dental procedures do seem to be good choices for laser surgery.

One of the risks involved in laser surgery is too much confidence in the laser as a tool to keep an inexperienced veterinarian out of trouble while doing difficult procedures. There have been articles in veterinary publications touting the use of lasers to make difficult procedures such as soft palate resection (shortening) into procedures that general practitioners can accomplish. While the laser may help in controlling hemorrhage, which is a major problem in these procedures, it does not help in learning how much tissue should be removed and overall evaluation of the patient's needs when these surgeries are performed. Experience really matters when surgery involves essential systems such as the airways. Try to be sure that your vet is not so enchanted with a new toy that he or she has become convinced they can do surgical procedures that are out of their league. Make sure that they have done the exact procedure that is being contemplated and that they have done the procedure enough times that you are comfortable with their experience.

Lasers are a good tool. They do not make surgery completely painless, they can't stop major bleeding and they don't make an ordinary surgeon into a gifted surgeon, though. Don't just routinely accept that it is necessary to have surgery done with a laser but don't rule it out when your vet can point out substantial benefits associated with its use.

 

Cytauxzoonosis felis

Bobcats have been making a comeback in some areas of the United States, especially in Texas, its bordering states, and Florida. This, combined with the prevalence of a tick known as Dermacenter variabilis, has led to the emergence of Cytauxzoonosis felis, a blood parasite, as a problem for domestic cats.

C. felis doesn't seem to cause much problem for its natural host, the bobcat. This is not true for domestic cats, though. This disease is fatal for the smaller cats we keep as pets. When an infected bobcat is bitten by a tick and then that tick reattaches to a domestic cat, the organism can be transmitted. It infects the red blood cells of the cat and kills them, making it impossible for the cat to carry enough oxygen in its bloodstream to survive. At the present time there is no effective treatment and no diagnostic test other than directly identifying the organism in blood smears, which can be difficult for veterinarians and veterinary technicians who are unfamiliar with the organism. Clinical signs usually appear about 2.5 weeks after the tick transfers the organism to the cat.

The only effective control measure is to prevent ticks of the Dermacenter variabilis species from attaching to your cat.

 

Tick Control in Dogs and Cats

Ticks can be killed by a number of medications for dogs but there is not much choice in medications for cats at the present time. The medications that kill ticks in dogs and cats do not have much repellent effect. They all take some time to kill ticks so even when the medications are working properly it is not unusual to find a tick crawling on a pet or even attached to the pet. Despite these findings, the following products are usually going to cause the death of the tick. Hopefully, at some time in the future it will be possible to find a medication that keeps ticks off of pets entirely.

In dogs, the best medications for killing ticks are amitraz (Preventic (collar) Rx), fipronil (Frontline Spray, Frontline Topspot Rx) and permethrin (many products, including BioSpot (tm), Defend (tm) and Hartz Control (tm). Most veterinarians rank the effectiveness of these medications in about this order, but there is some disagreement.

The amitraz impregnated collars provide effective tick kill for as long as three months and have a small amount of repellency. These collars are toxic if ingested and there are many reports of toxicity when one dog eats the collar off of another dog and a few reported incidences in which human toddlers have eaten the collars. For this reason, these collars should be used with caution in multiple pet households and are not advisable for households with toddlers. Amitraz collars are not considered to be safe for use on cats at the present time.

Fipronil is effective for approximately 30 days in both dogs and cats. Towards the end of the effective period it is not unusual to see ticks that have managed to attach to the pet prior to dying, at least in our practice. We find that the Topspot works better if all of the liquid can be applied directly to the skin. In order to accomplish this it is often necessary to separate the hair and apply a small drop to four or five areas of the skin rather than trying to put the whole vial of Topspot on one spot. Also, when ticks are the major problem, it can be very helpful to put one drop of the medication on the forehead above the eyes to prevent tick attachment around the eyes and face, especially when applying this to cats. It is necessary to avoid getting the Frontline in the pet's eyes, so this must be done carefully.

The permethrin spot on products that are between 45 and 60% permethrin are effective at killing ticks. Our experience with them makes us wonder why the companies claim that they last for thirty days, though. We find that if these products are more effective if they are applied every two weeks and at least one of them, Defend (tm) is approved for use this frequently. It can be used as often as once a week, if necessary.

If ticks are the only concern, the amitraz collars are the least expensive tick control method for dogs, followed by permethrin spot-ons and then fipronil. However, when both fleas and ticks are considered, it is least expensive to use fipronil, as it does a better job of controlling both ticks and fleas. In cats fipronil is the only safe and effective product for tick control that I am aware of.

 

Thanks for Your Support!

If you send us e-mail, remember that Michal Justis answers the e-mail at vetinfo@vetinfo.com. E-mail sent to mervet@inna.net is answered by Dr. Michael Richards.

The VetInfo Digest is published by:

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P.O. Box 476

Cobbs Creek, VA 23035.

The opinions expressed in this newsletter are those of Michael Richards, DVM., author.

 

Copyright 2002, TierCom, Inc.