When Danielle Richard-Fowler had a lung biopsy at the QEII Health Sciences Centre this spring, anesthesia was the last thing on her mind.
“It's a necessary part of surgery and not something you think about during the process,” she says.
Anesthesia is very safe but as people age, it adds risks of post-operative mental decline. Researchers at the QEII are trying to find out what causes it and how they can reduce the risk. Dr. Michael Schmidt, an anesthesiologist in the Department of Anesthesia, Pain Management & Perioperative Medicine, says the majority of his patients are older adults.
“The challenge is that we do anesthesia that works well for 40-year-olds but, if you are 80 years old, the same anesthesia may leave patients with post-operative cognitive decline,” he says. “In most cases, the family tells us their loved one is no longer the same.”
The incidence of some form of post-operative cognitive decline is described in the literature in 75 per cent of cardiac patients older than 65. It can range from mild to life-changing, Dr. Schmidt says, adding that medical professionals haven’t been able to measure the change as a first step toward improving care in a clinically feasible way in larger numbers of patients.
“It is a problem for the patient, who clearly sees they cannot perform like they did before. They get frustrated and upset because they cannot remember things like family birthdays. They are changed in their cognition and in their mood,” he says.
Dr. Schmidt engaged Dr. Gail Eskes, a Dalhousie University professor of psychiatry, psychology and neuroscience, to help design the test battery to measure cognitive abilities before and after a surgical procedure. The test will help them isolate the decline caused by the procedure from any other cognitive decline the elderly patient may be experiencing. “Anesthesia and surgery are affecting the brain on top of whatever’s going on in the brain already,” Dr. Eskes says.
A combination of pen-and-paper tests combined with a computerized test battery designed by Dr. Eskes and colleagues in the Brain Repair Centre, are used to gauge brain performance before and after surgery. “What we’re trying to do is define the best ways to measure the changes in cognitive abilities. If we can’t measure it, we’re not going to be able to figure out what’s causing it or identify things we can do to reduce the impact,” she says.
The first tests were done in the spring. Danielle volunteered to do one and found it challenging and a little taxing. One of the computer tests got her to click when a certain image appeared. “You have to be quick and click on the red card, for instance.”
She took the first test in October, had her procedure in April, and did the re-test in June. “I don’t feel any different. I don’t have more memory problems or any side effects that I can think of,” she says.“It’s very accurate if you want to gauge whether or not you've experienced decline. I think it was a good method of doing so.”
Yaeesh Sardiwalla, a medical student at Dalhousie University, is helping Dr. Schmidt and Dr. Eskes analyze the data as part of his Research in Medicine project. He’s also looking for ways to make it easier for patients to take the test.
“We can definitely see a possibility of it being on a computer tablet. You could have patients waiting to see the clinician, completing the test. As soon as it’s done, the results would feed into the electronic medical record,” Yaeesh says.
A better understanding of the risk of post-operative cognitive decline, especially comparing the preoperative cognitive status to the postoperative, is necessary to help patients make informed decisions and help medical professionals investigate ways to lower the incidence of cognitive decline.
“Making anesthesia safer is our goal,” Dr. Schmidt says.
And while Danielle felt fine after her procedure, she was happy to help other patients at the QEII, and is interested to learn about the results of this ground-breaking research.