Blood tests; when, why, and how do these help?

Veterinarians will sometimes recommend blood tests for your pet.

When is bloodwork helpful? It can rule out or reveal, certain problems, particularly useful to know in the following situations:

• • if your pet is going under general anesthesia or having a big procedure
  • if your pet is not feeling well, and we wish to gather information to investigate
  • when we are monitoring the success of a treatment or the progression of a disease
  • when we wish to monitor the blood levels of, or side effects of, a medication
  • or to obtain a baseline before starting a medication or treatment
  • even if your pet seems well, we may wish to screen for issues to catch & treat early

What information can we get from these?

• Depending on which tests are run, the following information can be obtained:
  • • Pre-anesthetic blood tests will show us red & white blood cells, blood clotting cells, blood sugar, kidney parameters, liver enzymes, electrolytes, and blood proteins. This is a general health screening tool. (Blood test results can strongly suggest normal health at the time the tests are performed, but cannot guarantee wellness, because there are some conditions that can’t be diagnosed using blood tests alone.) Pre-op bloodwork can be a helpful baseline, in case we need to compare to it in future. But mostly, it’s a tool to show the likelihood that the patient is well enough to have an anesthesia or a given procedure. The following values are part of a pre-anesthetic blood panel:
      • • Red blood cells – numbers & characteristics; a relative increase in numbers can suggest dehydration, while a low number tells us of anemia (which may be caused by bleeding problems or blood cell production problems in the bone marrow, sometimes influenced by age, inflammatory disease, kidney problems, etc.)
        • White blood cells – the numbers of these cells can indicate inflammation (sometimes due to infection), stress, bone marrow problems, etc.
        • Blood clotting cells – these are “platelets“. It is important that these cells are in normal numbers for their very important function in helping blood to clot (crucial during surgical and dental procedures).
        • Blood sugar values, when abnormal, can hint at problems with liver issues or possibly diabetes, and some other less common issues.
        • Urea & creatinine are tests that will give us hints about how the kidneys are doing.
        • Liver enzymes can tell us about suspected liver injury or bile flow problems.
        • Electrolytes (sodium & potassium) reflect potential issues with adrenal disease, kidney disease, and some other imbalances.
        • Blood proteins tell us about hydration, potential inflammation or some immune reactions, & liver status.
    • Full blood panels (same tests as in the bloodwork listed above, but with some additional measurements regarding calcium, phosphorus, more kidney, liver, & pancreatic indicators).
    • Examples of common additional tests are:  urinalyses, pancreatic enzyme tests, liver (bile acids) tests, cortisol measurements, antibody titres, thyroid tests, etc. These are used to get more health information, or investigate for specific conditions.