Importance of Pre Anesthetic Blood Work for Pets

Pre-anesthetic blood work is essential in any animal undergoing anesthesia. If you could go to Las Vegas, sit at a poker table and know what the dealers cards were, wouldn’t you? Anesthetic procedures are a gamble albeit the risks of complications are greater on the car ride to the hospital and not the anesthesia itself.

Having blood work done on your pet allows your veterinarian to see the dealer’s cards and increase your pet’s odds of having a complication free procedure. When pets are young, they can have congenital problems associated with their liver or kidneys that can alter how their body handles the anesthetic drugs. These issues often show no symptoms or signs for some time, which leads us to believe your pet is healthy and problem free. Truth is, we don’t know until we analyze the blood work and get a break down of what is going on inside of your pet. Often times, the blood work comes back normal and we are able to celebrate normal!

When we analyze pre-anesthetic blood work at Encina Veterinary Hospital, we are looking at the following values:
     – BUN, CREATININE, and PHOSPHORUS (related to Kidney function)
     – ALT, ALKALINE PHOSPHATASE, and BILIRUBIN (related to Liver function)
     – AMYLASE and LIPASE (related to Pancreas function)
     – TOTAL PROTEIN and GLOBULIN (related to the immune system and dehydration)
     – ELECTROLYTES (related to endocrine diseases, kidney function, and dehydration)
We often analyze other values, depending on the blood panel ran and what the needs of the pet are.

In adult and senior animals, issues such as organ dysfunction associated with old age changes or disease that decreases their ability to break down and excrete anesthetic drugs may arise, which makes pre-anestheic blood work even more essential. In addition to this, if their RBC (red blood cell) count is low, it makes it difficult for your pet to get enough oxygen (because these cells transport and distribute oxygen all throughout your pet’s body) and there are many complications that can arise including cardiac arrest.

It is important to know that many pets can have mild to moderate levels of organ dysfunction or anemia without actually appearing sick. Blood work that doesn’t come back normal doesn’t necessarily mean that your pet may not have the procedure done as expected; it may mean that your veterinarian may use a different drug that better fits your pet and their individual needs. Some times however, blood work tells us that the procedure is not able to be done at this moment for one reason or another. In times like this, your veterinarian will work closely with you and your pet in order to get him or her healthier.

Jared Jaffey, DVM

Anesthesia 101 for the Pet Owner

Having an anesthetic procedure performed can be a scary experience for both you and your pet, but it doesn’t have to be. If you know the right questions to ask your veterinarian or RVT (registered veterinary technician) that will be performing the anesthesia, it will help alleviate some of your anxiety and give you peace of mind.

Why do we perform blood work or an ultrasound prior to anesthesia at Encina Veterinary Hospital and how does this influence our anesthetic plan for your pet? Blood work and sometimes ultrasound aids us in looking for abnormalities within your pet’s organ systems. Some blood abnormalities we look for are low red cell counts (anemia), elevated kidney or liver levels, electrolyte abnormalities (electrolytes are things like potassium, sodium, chloride etc) or decreased protein levels in the blood. In addition, ultrasound helps us diagnose the severity of heart disease if your pet has a murmur or a mass/tumor in the body. These are just a few of the abnormalities that will help us determine your pet’s anesthetic plan. The medical history (previous medical problems or history of hospitalization) of your pet also aids in determining our anesthetic protocol. Anesthesia is NOT a one size fits all. We will choose the anesthetic drugs for your pet depending on its blood work, ultrasound results and medical history. Species and breed type can also influence our anesthetic plan. Sight hounds (Greyhounds, Whippets etc), brachycephalics (Pugs, English Bulldogs, Boxers etc) and cats, in general, can have different reactions to certain anesthetic drugs that differ from the majority of the pet population. Pets that are overweight, old (usually 9yrs or older) or very young (4 months or younger) also have anesthetic issues that can alter their anesthetic plans. All of this is taken into account when deciding on what anesthetic drugs will be safest for your pet.

Your pet will have many monitoring devices placed on it during anesthesia. The monitors help us make sure your pet has the safest anesthetic experience possible. We monitor your pet’s heart rate with an ECG as well as its blood pressure. Blood pressure is a VERY important vital sign to monitor. It tells us whether your pet’s organs and tissues are getting enough blood and therefore oxygen (blood carries oxygen that is vital in keeping your pet alive). The cells that make up tissues and organs can die if not enough oxygen is delivered to them. Initially this may not be a big deal, but if your pet has multiple anesthetic procedures and blood pressure is not monitored or is low your pet can start showing signs of organ disease. If blood pressure continues to be low during anesthesia we will administer fluids and sometimes drugs to help increase it. Low blood pressure is usually a side effect of most anesthetic drugs. Usually blood pressure returns to normal once anesthesia is discontinued. Carbon dioxide levels are also very important to monitor. If carbon dioxide starts increasing in your pet it can lead to very serious complications and eventually may lead to death. If carbon dioxide levels do start to increase during anesthesia, we will place your pet on a ventilator (a machine to assist your pet in breathing better). This DOES NOT mean that your pet has developed a breathing problem. Most of the drugs that we use for anesthesia cause respiratory depression i.e. breathing depth and frequency become decreased causing carbon dioxide to build up. Once your pet is recovered, breathing depth and frequency will usually return to normal. Oxygenation of the blood is monitored which aids us in making sure that enough oxygen is being transported by the red cells to your pet’s body. Your pet’s temperature is continually monitored with a temperature probe (like a big thermometer you use at home). This probe is placed in your pet’s throat or rectum depending on the surgical operation – don’t worry, the probes covers are changed after every surgical procedure. Usually your pet will have a warming device that blows warm air placed on top or under them to keep their temperatures normal. If your pet is small or sick, we may place two of these warming devices on them as these patients get cold quickly.

After your pet’s surgical or dental procedure is finished at Encina Veterinary Hospital, they will usually receive another dose of pain medication upon recovery. Again, this pain medication is chosen depending on their medical history. If you know that your pet has had a certain anesthetic or pain drug in the past and has not done well on it let the doctor or staff know so we can chose another drug. There are many newer anesthetic and pain drugs that are available to us. Your pet will recover in our ICU or preoperative area depending on the severity of their medical condition or surgical procedure. Patients that recover in ICU have many things that need to be monitored post operatively by our ICU nurses such as IV fluids or constant pain medications. Patients with moderate to severe organ disease will also be placed in ICU along with older healthy patients. Younger and healthier patients will recover in the preoperative area where they are watched by our surgical staff.

Anesthetic complications, though rare, can occur in any pet because ANY patient can have drug reactions that we can not predict. Some drug reactions can be reversed by using drugs that are specifically made for this purpose. Unfortunately, reversal drugs are only commonly available for opioids (morphine type drugs) and certain sedation drugs (Dexdomitor). Most other drugs can not be reversed so if a reaction occurs we can only support the patient with IV fluids and other drugs to minimize the reaction. Unfortunately, sometimes this is not enough and the patient may die, although this is EXTREMELY uncommon. We try to minimize all potential anesthetic complications by obtaining current medical history from you the pet owner as well as having current blood work on your pet. Records are reviewed by the surgical doctor as well as the RVT anesthetic staff the day of anesthesia. Again, once your pet’s history and blood work has been reviewed we will develop an anesthetic plan specific to your pet to minimize all potential complications and risks.

In addition, our anesthetic staff is the only staff in the entire Bay Area that is overseen by an RVT with a specialty in anesthesia (avta-vts.org). This allows our staff and doctors to be current on all anesthetic and pain drugs that are available including being current on new recommendations for their safe use.

Susan Burns BS, RVT, VST (Anesth)

Anesthesia Free Dental Cleanings

    Dental care is extremely important for our pets. As one of the ICU technicians at Encina Veterinary Hospital, I have personally seen the painful aftereffects of non-anesthetic dental cleanings performed by individuals (feed or pet stores, groomers) and I felt compelled to write about it (as well as some pushing and shoving [read: strong encouragement] from our blogger, Christina!) Although I am not one of the dental technicians, my heart breaks when someone brings in their pet with a tooth root abscess, or some other damage inflicted by an individual who “cleaned” their beloved pet’s teeth.

    Here at Encina Veterinary Hospital we recommend dental cleanings to our patients which require full anesthesia so that our Doctors and Technicians can do a safe and thorough job of fully examining, evaluating, cleaning and polishing your pet’s teeth. There are many places out there now that advertise non-anesthetic dental cleanings for very little money, who also convince/put the fear in pet owners that this is a safer technique than general anesthesia cleanings performed by licensed professionals like registered veterinary assistants and veterinarians. The problem lies in the fact that they may not be cleaning and polishing all the teeth properly. If teeth aren’t polished after scaling, bacteria can work its way deeper into the tooth cavity and create abscesses and many more (expensive) problems. It may seem like an easy and inexpensive alternative, but if not done correctly can be both expensive to your wallet, painful to your pet and even deadly.

    I know I have enough trouble trying to brush my dog’s teeth on the outside, never mind getting in all those nooks and crannies on the inside! And she certainly wouldn’t allow me to spend time scraping tartar off any of her back teeth and then polishing out the microscratches that the scraping leaves behind. The California Veterinary Medical Association (CVMA) opposed a bill (AB 2304) recently which would allow unlicensed individuals to scale pet’s teeth as long as it is with an unmotorized instrument without veterinary supervision. There are companies and websites out there touting the benefits of non-anesthetic cleaning, which are ill informed and send the wrong message to owners. They leave owners scared of veterinarians and general anesthesia, while subjecting your pets to harmful and scary improper dental cleanings. While cleanings here Encina Vet Hospital may be more expensive than the “cleanings” at your groomers, we have your pet’s best health and care in mind; we always treat your pets as if they are our own and we don’t lie to our clients to make a buck. Aren’t your pets worth doing what is right for them?

– Meg Davies, RVT


Here is an excerpt from Dr. Jill Christofferson’s advice article in the Contra Costa Times regarding anesthesia free dental cleanings:

When an animal is anesthetized, the area under the gum line can be properly cleaned using ultrasonic or sonic instruments and any pockets can be assessed and treated properly. The teeth are then polished. Dental X-rays and oral surgery can also be performed when needed. Many pet owners are frightened by anesthesia and think that having the teeth cleaned without it will be safer for their pet.

Anesthetic deaths do occur, and almost every veterinarian can tell of a death that occurred under their care. These deaths are rare, however, and the anesthetic agents currently used in veterinary medicine are considered very safe.

Animals who have had their teeth scaled without anesthesia can suffer from cuts to the gums, bruising of the skin due to excessive restraint, neck injuries, and even jaw fractures. I have known a few dogs who have had expensive and even life-threatening illnesses as a result of having their teeth cleaned in this manner.

The law in California states that performing dentistry on an animal constitutes the practice of veterinary medicine and needs to be done under the supervision of a veterinarian. The people performing anesthesia-free dental cleanings are not state-licensed or regulated and rarely work under a veterinarian’s supervision.

– Dr. Jill Christofferson

Susan Burns Presents at National Conference!

Throughout the year, veterinary professionals gather at national conferences to learn about new and emerging medical therapies and technologies. On August 29th, 2011, at the Central Veterinary Conference in Kansas City, Missouri, our own Susan Burns presented three lectures to veterinarians and technicians about anesthesia. Her topics included using ventilation, pediatric anesthesia, and geriatric anesthesia.

Susan Burns is a registered veterinary technician who also passed her certification process to become a Veterinary Technician Specialists in anesthesia. She is one of only a handful of VTS technicians in private practice, as most of them work in the teaching hospitals of the veterinary universities.

Susan’s experience speaking at this conference was rewarding. She felt like she was able to pass on practical information to others in such a way that they could translate what they learned into new policies for their own practices.

As a hospital, we are very proud of Susan’s accomplishments and her drive to share her knowledge with others.

Angela Linvill; Hospital Administrator