My practice requires preanesthetic testing for senior patients, and we strongly encourage it for younger patients, too. When clients ask if the testing is necessary, I explain that while we hope that test results will be normal, these tests can help us identify potentially serious conditions. I also give examples of cases where test results changed our surgical plans.

Here's an example: I was scheduled to spay my technician's 6-month-old kitten. "Go ahead and do everything," she said when she brought the kitty in. "Catheter, fluids, whatever you recommend."

"Do you want me to do a preanesthetic panel?" I asked.

I answered, truthfully, "Her exam results are normal and I see no red flags in her history, so the lab results will probably be normal, but better safe than sorry."

She agreed, and we ran a CBC and mini-chemistry panel. The CBC showed a marked leukopenia and neutropenia, which we confirmed on a blood smear. We postponed the surgery because of the risk of infection and delayed healing.

That same week we canceled two other elective procedures in different patients because of abnormalities found on preanesthetic blood work: thrombocytopenia in a puppy and hypercalcemia in a middle-aged dog. I've also diagnosed kidney failure and diabetes in apparently healthy pets that presented for elective procedures.

The key to effectively communicating the benefits of preanesthetic testing to veterinary clients is to emphasize that test results are usually normal, but abnormal values may alert us to undiagnosed problems that could impact the safety of anesthesia or the long-term health of the pet.

Dr. Laura McLain is an associate at Central Valley Veterinary Hospital in Salt Lake City, Utah.