When Your Rottie Needs Anesthesia

by Susan V. Hildebrand. DVM. DACVA

(From the American Rottweiler Club Newsletter “The ARK” )

When one of our beloved rottie family members needs anesthesia and surgery, it is quite natural to be worried. The most important thing to do is be informed. Have a good rapport with your veterinarian. You should be part of the decision making process. If you don't understand what is being recommended, ask again. A second opinion might be helpful. No one should mind - in fact you ought to be encouraged to get a second opinion if you just don't feel right about it.

I'm going to try to give you some tools to help you make informed decisions about anesthesia. It is a difficult balance between giving information and frightening people. There ARE risks to anesthesia. Anesthesia is truly controlled poisoning. I jokingly call myself an applied toxicologist! When an animal is rendered unconscious. it loses the ability to maintain it's own life-supporting relaxes. Ability to swallow, urge to breath, heart rate and rhythm, blood pressure - all these important functions are affected by anesthesia.

Many, many anesthetics are given without adverse circumstance. Fortunately. young, healthy animals are resilient. However, when something goes wrong in anesthesia, it usually means serious morbidity and mortality. Consider surgical complications. Often, a wound infection can be treated with antibiotics. A fracture which fails to heal can be managed another way. But in anesthesia, if the patient stops breathing, if blood pressure falls. if the heart stops, then the brain has very few minutes to survive. Anesthetic complications can be devastating.

What can you do to make anesthesia as safe as possible? First, make very sure that anesthesia is absolutely necessary. You won't find an anesthesiologist anywhere willing to submit to an unnecessary anesthetic!

PRE-ANESTHETIC WORK-UP

Let's start at the beginning. The first step is determining the health of the animal, and how that relates to risk- of anesthesia. We call this Patient Status. There is actually a numerical ranking for categories of young and healthy through to critically ill. To determine Patient Status, a complete history should be taken. especially with respect to previous illness, anesthetic experience, family history, and existing problems.

A complete physical examination should be performed.

Based on the above, if there are any questions, appropriate laboratory tests may be required. For example, a 6-month old healthy dog being neutered would not require much in the way of tests. The same 6-month old with a serious medical problem would require quite a bit of diagnostic testing, to make sure the problems are as well defined as possible. Age alone is an important consideration. At our teaching hospital. certain blood tests are done for any dog 5 years of age or older. Sometimes the need for laboratory tests will be evident even before the physical examination. When you report that your dog has a history of lethargy and inappetence, and has been coughing and drinking a lot of water lately.... Stop the presses! We need to find out what is wrong before we decide if and how an anesthetic should be given.

NPO

Freely translated, this little bit of medicaleze means “nothing per os”' or nothing to be taken by mouth. Your rottie should be NPO after midnight on the night before anesthesia, even the local anesthesia and sedation protocols. It is NOT OK to give him a little treat before YOLI head for the hospital the morning of surgery! 'Nothing' means no food and no water. Period.

DOES MY ROTTIE HAVE TO BE ASLEEP?

Maybe not. There are some options for rendering a patient insensible to pain. A good rapport with your veterinarian is a MUST so you can logically discuss the alternatives. Please don't misunderstand this unfortunate truth - many veterinarians are reluctant to even consider some of the following options, for good reason. In their unhappy experience, Rottweilers are large, strong, unruly, undisciplined animals with attitudes and no handles! They are only cute when they are asleep! It's very helpful if your veterinarian can learn your rottie's finer qualities. One of our adopting Rescue owners is a veterinary technician. She made me laugh, because she makes her co-workers give her pup physical examinations periodically. She wants him to be a good boy when he goes to the hospital. He. of course thinks everyone at the hospital is his friend. They are!

Maybe you can help with the procedure. Negotiate with your veterinarian to allow you to assist. There are legitimate reasons why this might not be the best approach. but you don't know until you explore it. For example, owner assistance could mean the procedure will take longer. Your veterinarian may also be nervous about liability. The prevailing spirit of litigation in this country puts veterinarians at considerable risk- if you are injured while holding your dog.

I know from experience that owner presence can just plain make everyone nervous - it's human nature. There are instances when I request an owner not be present. Some dogs are calmer and easier to handle with skilled technical assistance when the owners aren't there. Sometimes I can concentrate better and do a better job if the owner isn't there. You don't want to distract your anesthesiologist!

I myself accompany my animals everywhere they go in the hospital. I hold them and reassure them. And keep a watchful eve on everything that is happening. I just figure no one loves them like I do. Everyone is wonderfully supportive. Of course, it helps that everyone knows me and my dogs! They have confidence that my dogs WILL believe. The only time I leave my dogs is during surgery. I hold them until they are asleep, then I leave so the experts can do their job without me making them nervous. I have confidence in their skill, and know that everyone is doing their best for my kids. Do I worry the whole time they are :under”? You bet.

WHAT ARE THE OPTIONS?

Let's look at some options. Gentle restraint might be all that is needed. Taking radiographs is a good example of this. Yes, even OFA hip radiographs. The dog(needs only to cooperate with proper positioning.

Don't forget local anesthetics. so-called "freezing", as a wonderful option for analgesia. For example, a wound on an extremity or body wall can be infiltrated with local anesthetic and sutured closed. Or a small biopsy can be taken.

Local anesthetic techniques require patient cooperation. The surgeon must be confident that the job can be done with this approach. One of our anesthesiologists refers to "local plus coo-chi-coo". He means that the patient can be reassured and happy with someone giving all the right attention at the head. When I was in practice, I often presented local anesthesia as an option for the Sunday afternoon cut foot. The owners had to promise me they wouldn't faint though! And also that we would go to plan B (general anesthesia) if I couldn't do the job with plan A.

The two options above may or may not require light sedation. Heavy sedation is a different story - a good general anesthetic might be better than heavy sedation. There are a number of drugs and combinations to choose from. Now, I don't want to incur the wrath of veterinarians out there, but I have to comment on xylazine, trade name "Rompun'. Xylazine has some pretty tough side effects, and in my opinion there are other drugs which provide better,, safer sedation. Yes, xylazine can be reversed. Know that I would not sedate my own dog with xylazine.

GENERAL ANESTHESIA.

It may be that general anesthesia is the best option. This means the dog is rendered unconscious. All his protective reflexes are now in the care of the person administering the anesthetic. Anesthesia requires an understanding of the complex interaction of pharmacology, physiology, anatomy, surgery, and medicine. My Father is a physician anesthesiologist, and I remember. as a child. telling my friends what my daddy did. **He is the one who puts the patients to sleep. He is the one who keeps them alive". Did I get the party line young, or what!

Who administers anesthesia?

Most Board Specialist veterinary anesthesiologists work in an academic setting (teaching hospital), and are not easily accessible to most folks to actually do anesthesia for them. Some veterinary anesthesiologists actually do provide anesthesia services for private practices, but at present, these are few and far between. However, you or your veterinarian can always call a School of Veterinary Medicine and ask an anesthesiologist for a consultation if need be. Also, there are veterinary technicians who have special training in anesthesia, like nurse anesthetists. They work under the supervision of a veterinarian. Most practicing veterinarians are general practitioners. They do not have special training in anesthesia, but many of them administer a lot of anesthetics, and they are quite familiar with the drugs and techniques they use.

What about drugs?

There are many ways to give a safe anesthetic. One important rule is that the drugs with which your. veterinarian is most familiar are the safest in that veterinarian's hands. There are no perfect drugs. They ALL have side effects which need to be considered when selecting the anesthetic protocol.

There are two categories of general anesthetics. injectable and inhalation. Injectable drugs are usually used for inhalation (beginning) of anesthesia or for maintenance of anesthesia for short procedures. although infusion techniques for intravenous drugs are gaining popularity for long cases.

Most long cases are done with inhalation anesthesia. Drugs like methoxyflurane. halothane or isoflurane are volatile liquids. Their vapors are delivered in oxygen from an anesthetic machine. They are what people refer to as “gas anesthesia". Isoflurane is the newest of the three. It has gained considerable popularity. in part because it is associated with a more rapid recovery than the others. Isoflurane has some other advantages too. but it is more expensive than the others.

I could pick a word that describes the most important aspect of anesthesia, it would be "VIGILANCE". All the fancy bells and whistles in the world are useless if no one is paying attention to them. So when you take away the animal’s protective reflexes, it's of paramount importance to support and monitor the patient. Anesthetic emergencies seldom happen suddenly. The warning signs are there - if you are paying attention.

MONITORING.

What should be monitored? Ideally, we would know exactly what was happening to every cell all the time. No one has figured out a way to do that vet! So we have to make decisions based on information that we can obtain.

Monitoring techniques do not leave to be fancy to be good. The best equipment is probably the anesthetists own eyes, ears and hands.

Monitoring Circulation.

Blood pressure can be assessed simply by a finger on the pulse, or with a cuff and pressure manometer, or directly by placing a catheter in an artery. The latter is invasive and is usually done for critical cases. Heart Rate can be measured by the pulse pressure wave. Heart rate and electrical activity (rhythm) can be measured with an electrocardiogram. The latter reports only the electrical activity, not the pumping ability of the heart . The electrical activity of the heart can continue long after the pump has quit, so it is important to have both pieces of information. The color of the gums, and how quickly blood returns when one presses on them, is another simple way to assess whether circulation is adequate.

Monitoring Breathing.

During anesthesia, the animal might breath on its own, or may be mechanically ventilated. Adequacy of respiration is a little harder to evaluate without special equipment. Generally, one watches the chest excursions for rate. depth and rhythm, and again the gums for their pink color. A pulse oximeter can give information about the amount of oxygen carried in the blood. Pulse oximetry is relatively new to veterinary anesthesia, and is a useful but not perfect tool. Not everyone will have one.

There are other signs and systems to monitor too, but I won't go into any detail on them.

SUPPORT.

While anesthetized, the dog is unconscious, without its protective reflexes. An intravenous access, usually a catheter in the cephalic vein. should be placed before the dog is asleep and maintained until the dog is awake enough to hold up his own head, swallow, cough and breath. A secure IV means that emergency drugs can be administered quickly and effectively. No one should be struggling to place an IV in the panic of an emergency situation. A balanced salt solution should be given IV during surgery to replace the animals maintenance fluid needs, plus replace fluids lost in surgery.

A secure airway is a must. A tube. called an endotracheal tube, should be placed in the trachea right after the dog becomes unconscious. This tube serves several purposes. It makes it possible to deliver inhalation anesthetic and oxygen. The tube prevents blood. secretions, or foreign particles from going down the trachea and into the lungs. If the dog stops breathing, mechanical ventilation can be provided. The endotracheal tube should remain in place until the dog can fully control his own airway as he makes up.

As for venous access, an emergency situation is not the time to be struggling to secure the airway. I will never forget a scene from my internship days. A resident had heavily sedated a little fluffy dog for a cervical spinal tap and radiographs. The dog stopped breathing. and the resident could not intubate the dog. The dog died - for lack of a secure airway.

Body Temperature.

Animals get cold when they are anesthetized, so we usually monitor body temperature and provide warmth in the form of a circulating water blanket. Those are the safest to avoid thermal injure to a sleeping patient who cannot move if things get too hot.

A word on analgesia. Veterinarians used to be pretty cavalier about control of post-operative pain. Now there is a growing bank of understanding that pain management actually improves the course of healing for the patient. Our small animal anesthesia group routinely uses post-operative opiates (narcotics) or special blocks with local anesthetic to make animals comfortable after surgery. And yes, even the spays get post-op analgesia! Especially the mature girls feel pretty lousy after a spay, and it's nice to help them through the tough time.

THE LAST WORD. If your veterinarian wonders why all of a sudden you're asking about pulse oximetry and who will be monitoring my dog during anesthesia, you can lay the blame square on me. Maybe your veterinarian will have the patience to plough through this document. I have outlined simple, straightforward principles of anesthesia. Yes I am an academic, yes I work in the Ivory Tower, yes I have access to sophisticated techniques and equipment, and yes I am a trained specialist. All that being said, everything I have mentioned above can be done by anyone. anywhere. I have not discussed anything fancy - it's all part of our coursework for Junior veterinary students. GOOD LUCK!

Special thanks to Sue Hildebrand for this article.

(Previously appeared in RottNChatter.)