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PRE-ANESTHETIC BLOOD WORK & DIAGNOSTICS

Because of our strong commitment to providing the best medicine that we can for your pet, we strongly believe that regular blood testing is important in helping your pet to achieve a long and happy life.

What does the physical exam do for my pet?

A physical examination performed at a minimum of every six months will enable us to detect the presence of small problems or changes in your pet’s health before they can become major health problems.  A thorough physical examination alone is not capable of detecting all possible health problems.  It is impossible to obtain and understand a complete picture without also performing other tests.  Blood work gives us a means of checking your pet’s internal functions in a non-invasive manner.

Why does my pet need blood work if he appears to be healthy?

Even though our pets may appear to be healthy based on physical appearance and activity, many clinical signs of disease do not develop until late in the disease process.  Pets cannot tell us when they do not feel 100% and because of their instinct to protect themselves, many animals will ‘hide’ their illness.  A good example of this situation is a cat with kidney disease.  This patient may be afflicted with kidney disease for months to years before developing signs of disease because a pet can lose up to 75% of kidney function before clinical signs will develop.  Performing blood work will detect early changes in kidney enzymes and allow us to manage this disease process properly—allowing the patient to live a longer and healthier life. 

When should my pet have blood work performed?

Pets of any age can have problems with their internal organs.  Many young purebred cats and dogs will have congenital liver, kidney, and heart problems.   As pets age, their immune system and health starts to decline and they can have multiple organ problems.

Any anesthetic / surgical procedure

As discussed, a normal physical examination cannot give us complete confidence that the internal organs are working properly.  While the anesthetics that we use are extremely safe for your pet and therefore minimize risk, if a pet is not completely healthy then potential complications can occur both during and after the anesthetic procedure.  Pre-anesthetic blood work can alert us to any hidden problems that your pet may have.  With this knowledge, we may elect to forego the anesthetic/surgical procedure, modify the anesthetic regimen, or change your pet’s medication.  While performing blood work cannot guarantee that your pet will not have any problems with the anesthesia or surgical procedure, it can significantly minimize the risk to your pet and give both of us peace of mind.

Young animals

Blood work is recommended for young pets undergoing any anesthetic/surgical procedure.  Also if a problem such as liver or kidney disease is suspected, then blood work will help to identify this.  A significant percentage of young animals, especially purebred dogs and cats, can have congenital or hereditary problems such as portosystemic shunts (liver), kidney disease, hypoglycemia (low blood sugar), and diabetes.

Mature adults

While most pets experience the best health of their lives between the ages of two and six years of age;  stress, illnesses, and poor nutrition can affect and potentially cause disease to their organs.  Blood work at this point will detect these early changes and provide a good baseline for comparison to later on in the pet’s life.  Treatment is usually the most effective when begun in the early stages of the disease process.

Senior and Geriatric pets

We feel that blood work is of critical importance for our older pets.  For giant dog breeds, senior status is attained at five to six years of age.  Yes, we do not like to admit it, but our pets are senior citizens at seven years of age.  Because of rapid aging changes at this stage of your pet’s life, we highly recommend blood work on an annual basis.  We can compare current and previous blood results in order to evaluate the process of a disease and its response to therapy.  Common diseases include heart disease, liver and kidney disease, arthritis, diabetes, thyroid disease, and dental (tooth) disease.  Advances in medical diagnostics and treatment enable us to help your pet be more comfortable and also to prolong its life.  New pain management medications also help pets with chronic pain have a better quality of life.  In addition to medications, appropriate nutrition for your pet’s condition will also prolong its lifespan.

If my pet’s blood work is normal then have I wasted my money?

Absolutely not.  A normal result on blood work is great!  We now have a baseline for how your pet is doing at this time.  If future blood work reveals changes, then we can tell how long the problem has been going on and are assured that we are indeed catching the problem early.  Normal blood work results give both of us peace of mind that your pet is doing well.

What kind of blood work do you perform?

Complete Blood Cell Count 

This test provides information about the various types of blood cells.  Red blood cells carry oxygen to tissues.  White blood cells are the body’s primary defense against infection.  Platelets are involved in the clotting process.  Abnormalities with any of these values help to potentially detect anemia, inflammation, acute or chronic infection,  bleeding disorders, blood parasites, dehydration and autoimmune diseases.

Comprehensive Serum Blood Chemistry

This is a series of individual tests that analyzed together give us valuable information concerning the kidneys, liver, pancreas, intestinal tract, and endocrine diseases.

BUN, CREATININE, and PHOSPHORUS—kidney

ALT, ALKALINE PHOSPHATASE, and BILIRUBIN—liver

AMYLASE and LIPASE--pancreas 

TOTAL PROTEIN and GLOBULIN—immune system, dehydration

GLUCOSE—diabetes, insulin tumor

CHOLESTEROL—hypothyroidism, cushings disease, pancreatitis

CALCIUM—kidney disease, hyperparathyroidism, some tumors

ELECTROLYTES—endocrine diseases, kidney, and dehydration

Are there any other types of tests that may need to be done on my pet?

A CBC and Comprehensive Chemistry are good screening tests to help detect health problems for your pet.  Sometimes other diagnostics may be recommended based upon these results.  Some of these involve specialized tests at outside laboratories.  Some of the more common diagnostics involve:

Thyroid:  Hyperthyroidism is extremely common in older cats.  It can cause hypertension, heart disease, and weight loss.  Dogs tend to get hypothyroidism which causes weight gain, problems with the hair coat, and other problems. 

Urinalysis:  This will help to detect kidney disease, diabetes, infection, inflammation, and metabolic disorders.  Kidney disease is first evident here. 

ECG (Electrocardiogram):  This enables us to see the electrical activity of the heart.  Abnormalities may indicate a serious problem and a chest x-ray or cardiac ultrasound may be recommended.

Ultrasound:  This is a specialized piece of equipment that allows us to obtain a three dimensional image of your pet’s organs.  We can visualize the heart, liver, spleen, kidneys, stomach, intestines, pancreas, adrenal glands and bladder.  When diseases of the liver or kidney are detected, the ultrasound can give us a look at the internal structure of these organs and allow for ultrasound guided biopsies to help further identify the cause of the disease.  We strongly recommend an ultrasound on all of our cardiac patients, especially cats.  Older cats are prone to HCM—Hypertrophic Cardiomyopathy.  This is a disease in which the heart muscle hypertrophies, decreasing the available volume of blood to be moved through the heart.  Radiographs will not diagnose this disease;  it can only be diagnosed via ultrasound.  This disease is fatal without specific and appropriate medical management.

Blood Pressure:  Many older cats become hypertensive, especially with hyperthyroidism and/or kidney disease.  Older dogs can also get this disease. This machine works much like the blood pressure monitors in human medicine.  The test is quite simple and easy to perform.

X-Rays (Radiographs):  These can help to detect problems with the heart, lungs, kidneys, liver, bones, soft tissue and intestinal tract.  They are used to identify disease and also to monitor progress/response to therapy.  X-rays are an essential component in the work up of heart patients.

Note: This article is provided by Claws & Paws Veterinary Hospital® for informational purposes only.