Pre-Anesthetic Lab Work


Pre-operative blood testing helps ensure safe anesthesia for your pet.  Questionable or minor variations in results may be double checked or cross-referenced with a urinalysis and may influence the type of anesthesia or used.  Significant abnormalities will lead to deferment of the procedure while additional testing is done.  The parameters we check evaluate your pet’s kidneys and liver, and test for diabetes, anemia, and blood clotting deficiencies.  The following provides more details on the eleven parameters we test:

BUN (blood urea nitrogen) is influenced by kidney function, liver function, diet, and hydration status.  BUN is a waste product produced by the liver from proteins in the diet.  BUN is excreted by the kidneys and will elevate with kidney disease, a high protein diet, or dehydration.  Urine concentration is dilute with kidney disease and concentrated with dehydration.

Creatinine is a waste product that originates from muscles and is excreted by the kidneys.  Creatinine will elevate with kidney disease and dehydration.  Creatinine is a slightly more sensitive indicator of kidney disease than BUN.  Urine concentration is dilute with kidney disease and concentrated with dehydration.

ALT (Alanine Transferase) is an enzyme produced within liver cells.  Elevations of ALT indicate inflamed or damaged liver tissue.  The level of elevation does not correlate well with severity of disease and cannot be used as an indicator of disease reversibility

SAP (Serum Alkaline Phosphatase) originates from many tissues in the body.  In dogs it most commonly elevates from liver disease secondary to hyperactive adrenal glands.  Elevated SAP in cats is a strong indicator of liver disease.

Glucose is blood sugar.  Diabetes mellitus causes increased blood sugar.  Temporary increases in blood sugar are seen with excitement or stress.  This is especially true in cats.  Prolonged elevations in blood sugar result in glucose excretion in urine.

Total Protein is a measurement of albumin and globulins in the blood. Increases can be a reflection of patient hydration or stimulation of the immune system by infection or cancer.  Decreases can be seen with gastrointestinal loss, some forms of kidney disease, or failure of the liver to synthesize albumen.

Electrolytes (Sodium, Potassium, Chloride) can be affected by many things, including hydration status, adrenal gland function, gastrointestinal disease, and kidney disease.

PCV (Packed cell volume) is a measurement of the percentage of red blood cells in circulation.  It increases with dehydration and decreases with anemia.

Clotting time is a test that assesses platelet function and the clotting factors that platelets use to form blood clots.  Delayed clotting times can be seen with inherited diseases, liver disease, vitamin K deficiency, toxicity from certain rodenticides, and some medications such as aspirin.

Urinalysis, although not routinely run as a pre-op lab test, it is a good confirmatory test if lab work is suggestive of kidney disease, diabetes, protein disorders, or dehydration.