Almost every dog or cat will have to be
anesthetized at least once in their lifetime, with the majority of pets
receiving anesthesia several times. The reasons for this can vary from a spay
or neuter in a young, healthy animal to a dental procedure in an active, middle
aged pet to a cancerous mass removal in an older, perhaps somewhat health
impaired patient. However, the one thing all of these scenarios have in common
is our dedication to providing a safe and effective anesthesia experience.
At
Pearl Animal Hospital we take anesthesia very seriously, and we have a
pre-operative protocol to ensure your pet’s safety. This includes the
requirement of a recent examination and pre-anesthetic lab. This is extremely
important because a physiological abnormality can be diagnosed during this
process that may have otherwise gone undetected. These abnormalities can
include findings such as a heart murmur, anemia, or elevated liver or kidney
values, just to name a few. Oftentimes, this does not mean your pet should not
undergo his or her procedure, but rather more in depth diagnostics should be
performed. In any case, it is imperative to have that knowledge, which allows
us to create a more individualized and appropriate anesthesia protocol for our
patient.
On
the day of your pet’s procedure he or she will be examined again by the
veterinarian performing the procedure. About 30-60 minutes before the induction
of anesthesia, your pet will receive an injection of an opioid and
occasionally, a sedative. These medications
help relieve pain & anxiety and help provide some relaxation. We try to
limit stress as much as possible in our patients. Once the first injection has
taken effect we place an intravenous (IV) catheter. This is a very important part of the
anesthesia process. The IV catheter provides a constant infusion of IV fluids
during the procedure to aid in hydration and assist in keeping the blood
pressure within a normal range. The IV catheter also allows direct access to a
vein to allow us to administer additional medications during the procedure if
needed. Once the IV is set we are ready to start the induction of anesthesia.
Our
patients receive two medications through their IV catheter: an anti-anxiety
medication (Midazolam) and an injectable anesthetic (Propofol). These medications
take effect pretty quickly, and before he or she has a chance to count to ten
our patient is asleep. Once asleep we are able to place an endotracheal tube
into the trachea (wind pipe). This is important because it protects the airway
and ensures your pet is properly oxygenated and anesthetized. That tube is then
connected to the anesthetic machine where oxygen and gas anesthesia
(Sevoflurane) are administered, the amounts of each are tailored to each
specific patient.
The
anesthesia process is now well on its way with close and constant monitoring. According
to the University of Minnesota, “It is important to realize that anesthesia is
not a simple thing. It has profound effects on an animal's physiology because
of the generalized central nervous system effects as well as specific effects
on all other body systems.” These effects include the possibility of a slower
heart rate, lower blood pressure, slower respiratory rates, and a lower
temperature. All of our anesthetized
patients are monitored by several machines as well as a dedicated Certified
Veterinary Technician (CVT). This CVT’s only responsibility during the
procedure is to monitor the patient. He
or she regularly examines the ECG and records the heart rate, blood pressure
values, temperature, respiratory rate, end tidal CO2 (the amount of
carbon dioxide the patient is exhaling), and SpO2 (the percentage of
oxygen circulating in the red blood cells). These are all important vital
signs, and they are all tied very closely together. If one value falls outside
of the normal range, it is very likely other values will follow. Fortunately,
because we monitor so closely we are able to anticipate and detect an abnormal trend
or value and proactively intervene. This will help prevent abnormal parameters
or problems from occurring. These
interventions can, among other things, include adjusting the anesthesia rate,
adjusting the IV fluid rate, and administering medications. After the completion of the procedure (which
can range from 30 minutes to 5 hours), gas anesthesia is discontinued and your
pet is disconnected from the monitoring machines. However, he or she is never
disconnected from the team members monitoring him or her. Following anesthesia,
every patient is continuously monitored by several staff members to ensure your
pet continues to have an uneventful recovery.
With
the advent of more advanced drugs over the past several years, anesthesia is
becoming a far safer process, but it is certainly not without risks. In fact,
anesthesia is the biggest risk for the majority of procedures your pet will
receive. But, because all team members at Pearl Animal Hospital are aware of
and appreciate these risks, you can rest assured knowing that your pet will be
in great hands during his or her procedure.
