Pre-Anesthetic Blood Tests: Jack’s Test Reveals Kidney Failure
Many illnesses can go from undetectable to potentially deadly (particularly when combined with surgery and/or anesthesia) over the course of just a few weeks.
Having fresh blood work provides insight into your dog’s overall health making sure that they can handle anesthesia safely. It is important to adjust the treatment plan if the blood test reveals any abnormalities.
Knowing is always better than not knowing.
Gregory House/House MD
I remember when Jasmine was to go under anesthesia for the first time to get her spay. We got an estimate with an optional pre-anesthetic blood test. I remember us deliberating whether or not we should add that expense. In the end, as you might guess, we decided that we wanted everything to go as safely as possible and asked to have the blood test included. We didn’t have much money but we didn’t want to take any risks with Jasmine’s well-being.
Pre-anesthetic blood testing can be life-saving.
I don’t believe that a pre-anesthetic blood test should have been optional.
Since then, pre-operative lab work has become part of the standard of care. If you do have the option to turn it down, don’t.
Even though we never got any surprises about Jasmine’s health, we would put any of our dogs put under without doing the test first. Why? Because you never know.
With our vet, we had the rule that if the last blood test was older than a month before the procedure, we’d run it again.

Jack’s story
Jack was a healthy senior dog, going in for his dental. He was drinking and peeing a little more during the weekend. But otherwise, he seemed perfectly fine. Before the procedure, he had his pre-anesthetic blood test done, even though it wasn’t all that long since his last blood draw which was normal.
Jack’s pre-anesthesia blood test results
Jack’s results presented an unwelcome surprise—his kidneys were failing.
His creatinine and BUN were elevated. And his dilute urine confirmed the findings. Jack’s dental had to be put on hold and Jack was scheduled for an abdominal ultrasound with a specialist the next day.
Fortunately, the ultrasound didn’t reveal any further surprises and Jack could get his dental done.
Jack’s adjusted anesthesia protocol
His anesthesia protocol was adjusted to his condition.
With kidney failure, anesthesia needs to be focused on maintaining circulation and oxygen levels. Any abnormalities, such as high blood pressure, dehydration and electrolyte abnormalities … need to be corrected before anesthesia takes place.
Further information: AAHA Anesthesia Guidelines for Dogs and Cats
Most anesthetic drugs don’t directly affect the kidneys but can decrease blood flow to the kidneys, so drugs that preserve cardiovascular function are preferred and other measures might need to be taken.
Jack’s procedure
Jack’s procedure went well and he got his teeth all fixed up.
How smoothly do you think things would have gone without doing the pre-op test and not knowing that his kidneys were bad?
Knowing that Jack’s kidneys were failing also allowed to take measures to protect them from further decline. Because he no longer could get NSAIDs, his arthritis was managed with acupuncture and trigger point therapy. His diet was changed and he was put on herbs that support kidney function. He’ll have regular blood and urine tests to monitor the development of his disease.
Kidney failure is a life-changing diagnosis. But knowing about it allowed taking measures to keep Jack as healthy and happy as possible for as long as possible.
Knowing is life-saving.!
Related articles:
Kidney Disease in Dogs – Say What? Canine Kidneys and the Associated Verbiage
Kidney Failure in Dogs: What Happens In The Dog’s Body When The Kidneys Fail To Function Properly?
Further reading:
Preanesthetic Bloodwork