Every pet is different and anesthesia protocols should be customized to meet the specific needs of the individual. For example, a senior pet or one with a health problem would probably require a different anesthesia protocol than a young, healthy dog or cat.
The word anesthesia is of Greek origin and means absence of sensation. In the mid-1800's it took on its present day use as a term to describe induced insensibility (unconsciousness) to pain during surgical procedures.
There are two kinds of anesthesia: local and general. Local anesthetics are used to numb a specific area of the body.
General anesthesia is the kind that renders the patient unconscious and is of course the more worrisome and potentially dangerous of the two. However, human and veterinary medicine have seen significant improvements in recent years in anesthetic agents with highly predictable and reversible effects.
General anesthesia is used with pets to help relax the muscles of the body, remove the ability of the animal to fight against the procedure, and to insure your pet feels no pain during surgery or other veterinary procedures.
What Are the Risks of Anesthetizing My Pet?
It is thought about 1 in 100,000 animals have a reaction to anesthesia. To the owner of that 1 in 100,000 dog or cat, it's a completely unacceptable risk. But it's actually less risk than your pet faces riding in the car to and from the vet's office.
Reactions can be as minor as a bit of mild swelling at the injection site, to a life-threatening situation of anaphylactic shock.
If your pet has a medical condition (for example heart, liver or kidney disease, diabetes, anemia, dehydration, or an infection like heartworm disease), there is an elevated risk of complications from anesthesia.
Also if a pet isn't fasted properly prior to anesthesia, she can encounter problems like vomiting either during or shortly after being anesthetized. This can result in aspiration pneumonia, which is a very serious condition.
Other complications from anesthesia, though rare, include blood clotting disorders, problems with eyesight, seizures, and kidney, liver or heart failure.
Evaluating Your Pet's Condition Pre-Anesthesia
Things you should expect your vet to do before performing a procedure requiring anesthesia include the following (some of this will depend on how well the doctor knows your dog or cat already, and when your pet was last examined):
- Take a complete medical history including pre-existing conditions, prior surgeries, vaccine status, spay/neuter status, results of any previous testing, supplements and medications given, known drug reactions, and how your pet has reacted to anesthesia in the past.
- Perform a thorough physical to include gum assessment (which shows how well hydrated your pet is as well as his circulatory status), chest exam and palpation of the abdomen.
- Pre-anesthesia blood tests and a chest x-ray, ECG or BNP blood test, if appropriate.
If your vet determines your dog or cat can safely undergo anesthesia, you'll typically need to fast him for 12 hours prior to the procedure. Vets have differing opinions on how long before surgery water or other liquids should be withheld, but the minimum time is usually two hours prior to pre-medication.
In debilitated pets, the goal is to stabilize the animal before anesthesia is attempted.
Pre-Medication and Anesthesia Options
Prior to anesthesia, an IV catheter and line should be placed in your pet so the doctor and vet staff can easily administer drugs, including anesthetics, as well as fluids.
IV fluids are beneficial for blood pressure maintenance, to replace fluids lost during surgery, to accelerate the recovery process, and to prevent post-anesthesia kidney dysfunction. The IV will also be used in the event emergency drugs are required during the procedure.
All older general anesthesia patients should receive IV catheterization and fluids, and many vets suggest or require a catheter for all patients.
Your pet should also be pre-medicated with a sedative, which will help the induction (start-up) of the anesthesia and can also improve its effectiveness during the procedure.
Your vet has many choices of pre-anesthetic sedation available, depending on your pet's health evaluation. At my clinic, I prefer Butorphanol for healthy pets because it also offers some pre-surgical pain management (which has been proven to reduce post-operative pain levels).
There are also a wide variety of anesthetics available for veterinary use. Most of them are listed here, with an explanation of how they work, side effects, situations in which they are used, and other information.
The anesthesia I prefer is Sevoflurane, which is an inhalation agent. Inhalation anesthesia provides some advantages, including a patent (clear and unobstructed) airway, fast control of the depth of the anesthesia, and a rapid, uneventful recovery.
Your pet will have an endotracheal or breathing tube inserted which will facilitate delivery of the anesthesia gas to the lungs, as well as oxygen as required.
Monitoring Your Pet During and Immediately After the Procedure
Your pet's condition should be continuously monitored while she's 'out' and then in recovery until she's no longer under the influence of the anesthesia. Typical vitals measured include:
- Body temp
- Respiration and pulse rates
- Blood pressure
- Blood oxygen and CO2 (carbon dioxide) levels
- ECG or EKG
I recommend asking your vet how they monitor these parameters, as well as control body temperature during anesthesia.
Your pet should appear normal to you by the time you pick her up after a procedure during which she received anesthesia.
You might notice she's a bit sleepy and less active for 12 to 24 hours after you get her home. But if she seems really sluggish, groggy, or out of it, call your vet or an emergency animal clinic right away.
Post-surgery Pain Management
If your pet has had surgery of any kind, he'll be in pain – perhaps just a little, perhaps quite a bit. And he can't tell anyone if or how much he hurts, so you'll need to speak up for him if necessary.
Your dog or cat should be treated before, during and after any pain-inducing procedure with appropriate pain relief.
Pain medication will not only keep your furry family member comfortable, it will also help speed up the healing process. I strongly believe all patients that have been cut with a scalpel deserve prescribed pain management, at least for the first 72 hours. If your vet does not offer pain management, please ask for it.
I recommend everyone, on two legs or four, see a chiropractor or bodywork therapist after any procedure requiring anesthesia. This is particularly important for pets, since while many hospitals and surgery centers now put human patients on 'anesthesia boards' to transfer them from the gurney to the surgery table and back to the gurney, many pet patients aren't handled as carefully.
A limp body is difficult to lift and move. All that flopping around can throw your pet's body out of alignment during transfer from the surgery table to the recovery area.
Also, many animals jerk their bodies around as they awake from anesthesia, which can also damage their skeletal health.
In my professional opinion, allowing an animal chiropractor to realign your pet after any round of anesthesia is money well spent.