I Remember When…
We Believed Anesthesia Might be Too Risky
The thought of anesthesia produced anxiety for several reasons.
- Fear of the unknown
- Fear of loss of control associated with loss of consciousness
- Fear of waking up during surgery
- Fear of not waking up!
Some of this fear may have been related to thoughts of pain, including the IV catheter insertion, but a lot of it was due to prior experiences, either personally, or with our own pets, or through the stories of others.
The Good of Anesthesia
Fear of anesthesia today may lead pet owners to avoid very important procedures for seriously painful health problems, which is unfortunate. Thankfully, we are fortunate that advancements in pain control and anesthesia have made a big difference to the suffering of animals.
So what is misconception, and what is truth in this day and age? If we are basing our beliefs about anesthesia on outdated information, we may be missing out on life-improving, life-extending, even life-saving treatments.
The Past 50 Years and the Client Consent Form.
Thankfully, the anesthesia experience has transformed from a practice with significant mortality risks into one of the safest components of modern medicine.
Even though anesthesia is very dependable, we still inform pet owners of any potential risks before surgery is performed. Then we ask if they give permission to start CPR (cardiopulmonary resuscitation) if that is needed. If there were to be a sudden change in a pet’s status while under anesthesia the situation could develop quickly, and treatment like CPR must be started immediately. These things are tough to discuss but are required as part of the legal client consent form whether the procedure is routine or not.
The truth is, though, that the risk of dying from anesthesia has decreased by roughly 90% over the last 50 years. There are multiple reasons.
Individual Patient Safety Considerations
-Nowadays each patient has a comprehensive anesthetic plan based on their pre-anesthetic screening (physical examination, history, diagnostic workup) and the procedure to be performed.
– The introduction of checklists in veterinary medicine, similar to human medicine, has improved team communication and reduced human error.
Technique Improvements
-There has been a shift to much better overall support of the patient, with intravenous fluids, external warming throughout the surgery and recovery, and continuous charted monitoring by a dedicated, trained technician.
Technology
-Modern advanced monitoring equipment tracks important parameters such as Oxygen and Carbon dioxide content of the blood, ECG, and blood pressure. These all give early indications of a change in response to anesthesia at the same time as we are following heart rate, respiration rate, and temperature.
Drugs
-Safer gas anesthetics are available, and the injectable drugs offer a much wider range of approaches. Key advancements are the development of “multimodal pain management” with drugs to interrupt pain before, during, and after surgery, as well as “balanced anesthesia”.
-Multimodal pain management is the use of Non-Steroidal Anti-inflammatory Drugs (NSAIDs), opioids, nerve blocks, and local anesthetics together to ensure pain is managed along more than one pathway.
-Balanced anesthesia is the use of lower doses of several drugs (e.g., benzodiazepines, alpha-2 agonists, opioids) to minimize the adverse effects of any single agent, which improves overall patient safety.
-Reversible drugs (e.g. dexmedetomidine) allow for a faster, smoother return to consciousness, reducing risks during recovery.
-We’ve gone from ether and chloroform gas agents for maintaining anesthesia to isoflurane, sevoflurane and desflurane, which provide faster, smoother, safer and more predictable anesthetic “induction” and recovery. Modern anesthesia machines which deliver anesthetic gas and oxygen are designed for high precision.
-The newer injectable anesthetics (e.g. Propofol, alfaxalone) provide ultra-short-acting options and better cardiovascular stability than the old barbiturates.
Training
-Training is an ongoing process, but the field has grown exponentially to be a detailed and fascinating specialty. Still, there are protocols that can be relied upon to provide predictable, safe results in the vast majority of standard surgeries.
Professional Dental Cleanings: Why Anesthesia Is Necessary
Even with the best homecare possible, most pets will need professional dental cleanings, just like people do. This article includes an explanation for why anesthesia-free dental cleanings are inadequate, and potentially dangerous:
https://chippawavet.com/news/more-than-bad-breath-the-risks-of-ignoring-your-pets-oral-health
Radiographs: Why Anesthesia may be Recommended
Taking an X-Ray involves careful positioning and the patient must hold still for at least a short period of time. Some of the nicest squiggly pets can be a challenge in this respect. The important consequence of this is that a pet patient can put themselves and the animal hospital staff at risk of injury with an otherwise routine procedure. If we must perform this important diagnostic test with sedation we will let you know.
Using “Local Freezing”
We get asked fairly frequently about using a “local” instead of “putting them out”. Drugs such as Lidocaine and Marcaine are injected into tissues to numb sensation. We use them mostly in anesthetized animals during dental procedures to smooth the recovery. As most of us can attest, after our own tooth procedures we feel “frozen “ for a few hours.
The dentist is putting in local anesthesia, and it is very helpful in the early period after surgery. Veterinarians and dermatologists do sometimes also use local anesthesia for something like a wart removal in an awake patient, but it can produce some problems in practice.
OUCH!
The injections sting, causing the pet to react if they are awake, and making them more anxious. This can give the pet an aversion to coming to see us, and make them very fearful of further visits. Restraining anxious pets puts our “holders” at greater risk for injury. An injury could be a serious bite or scratch.
No Effect
Sometimes the desired effect isn’t produced. There is a maximum dose that can be given, so it isn’t a matter of “more is better”. In these cases we have to ask our pet parents if we can use a general anesthetic, anyway.
Size matters
Because of dosage restrictions, only small skin lumps can be removed using local anesthesia.
Getting consistent local anesthesia without these issues would be wonderful. Maybe this will be the next area of advancement. With all the changes over the last 50 years, the one thing we can say for sure is that
“To improve is to change; to be perfect is to change often.” — Winston Churchill