When to Say Yes to a Diagnostic Test

As veterinarians, we have access to so many incredible diagnostic tests for our patients. The tests can help us uncover medical problems that, in the past, we could only guess about. The downside of having all this diagnostic ability at our fingertips, however, is that we must all — veterinarians and clients alike — sometimes tackle difficult decisions about which diagnostic options to pursue for our pets.

How can you know whether or not to say yes to your vet when he or she recommends a diagnostic test? Here are my suggestions for how to think this through:

Begin by talking with your veterinarian about all the potential risks and benefits associated with the recommended testing. What will be involved for your dog or cat (anesthesia, hospital stay, risk of complications), and what will be involved for you (time, expense)?

Ask Yourself Two Simple Questions

Before making a decision about whether or not to pursue recommended testing, consider the following:

1. Will the results of the testing have the potential to change what I do next?
2. Will the results of the testing have the potential to provide me with some peace of mind?

If you answer yes to one or both of these questions, then it is reasonable to consider proceeding with the recommended diagnostics. If your responses are "No," however, then more testing is harder to justify. In such cases, you may be subjecting your dog or cat to pointless procedures.

Real-World Examples of How These 'Decision Trees' Can Work

Here are a couple of examples from my case files that show how answers to the questions I have posed above can help guide you in your decision-making process.

Shasta

This sweet-as-can-be 12-year-old Golden Retriever mix was brought to see me because of vomiting and loss of appetite. An abdominal ultrasound revealed multiple masses within her liver, stomach, and spleen. I told Shasta's mom that I was 99 percent certain I had identified cancer involving multiple organs. Surgical removal would not be an option (the disease was already too widespread). Therefore, the only option for potentially helping Shasta would be chemotherapy, assuming that the cancer was a type that would be responsive to cancer-fighting medications. We discussed the risks and benefits of performing an ultrasound-guided biopsy to "name the enemy" and determine its sensitivity to chemotherapy. Shasta's mom was certain that she would wish to give chemotherapy a try, so she opted for the biopsy procedure. Moving forward in this case made sense, as the results of the diagnostic testing had the potential to change or guide what would happen next.

Shasta handled the biopsy procedure beautifully and was diagnosed with lymphoma. Her cancer responded to chemotherapy, and she, for the time being, is back to being her happy, lively self.

Pixel

A history of coughing is why this 12-year-old kitty came to see me. Chest X-rays revealed multiple lung masses, and I told Pixel's family I was 90 percent certain they were cancerous growths. I left the 10 percent door open to the possibility of an unusual infectious disease. Pixel's family members and I discussed further diagnostics, including a computed tomography (CT) scan of the chest cavity and an aspirate or biopsy of one of the masses in order to firm up the diagnosis and determine if we might be able to provide effective treatment. Pixel's family, however, felt certain that if he had cancer, they would not wish to treat it. The 90 percent certainty that their little boy had cancer was enough to provide them with peace of mind about their decision. Pixel's family took him home and is managing him with cough suppressants, pain medication, and lots of TLC in order to keep him comfortable until the need for euthanasia becomes evident.

Both these cases show that medical decision-making is never easy, particularly when advocating for patients who cannot speak for themselves. Gathering information, asking the right questions, and spending some nose-to-nose time with that wonderful animal of yours can make all the difference in terms of deciding what to do.

Have you ever found yourself in a decision-making dilemma concerning diagnostic tests for your pet? What helped you make your decision? Tell us in the comments box below.

Dr. Nancy Kay graduated from Cornell College of Veterinary Medicine and is the author of Your Dog's Best Health: A Dozen Reasonable Things to Expect From Your Vet and Speaking for Spot: Be the Advocate Your Dog Needs to Live a Happy, Healthy, Longer Life. Dr. Kay is a specialist in small-animal internal medicine at Upstate Veterinary Specialists, with offices in Asheville, N.C., and Greenville, S.C.