Beloved piano teacher's death sparks call for better drug monitoring in hospitals

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Wendy Guimont's tumour didn't kill her. But a cascade of errors tipped the scales.

The beloved piano teacher inspired and trained music instructors for children across Canada. A go-getter who loved to hike, bike and golf, the Cranbrook, B.C., resident and her husband jumped at the chance to drive an RV to Arizona.

While in the U.S., back pain Guimont had initially brushed off worsened. On Valentine's Day in 2021, she learned she had metastatic pancreatic cancer. Remarkably, her family says, she gained weight and strength while on chemotherapy. Then, on July 8, 2023, she died — not of cancer, but of kidney failure following a severe drug reaction to the antibiotic vancomycin.

"It's just sad because I feel like she could have fought a lot longer and who knows, with my mom, if we didn't have kidney failure to deal with on top of cancer," said daughter Penny Guimont of Grafton, Ont., about 120 kiometres east of Toronto. 

Vancomycin is an antibiotic commonly prescribed to treat infections such as staph. It comes with risks, particularly when the treatment lasts more than a week and in certain patients, such as those aged 65 (such as Wendy), or older. That's why doctors developed guidelines saying vancomycin levels, when delivered intravenously, need to be carefully monitored and timed to determine whether the dose needs to be adjusted, drug safety experts say. 

But staffing and other challenges in hospitals mean important steps can be missed or delayed, leading to severe kidney injury, or as in Guimont's case, death.

Continuous vancomycin can injure the kidneys, and about 10 per cent of patients given standard doses of the drug develop vancomycin-induced kidney damage — also known as nephrotoxicity. Those critically ill in ICU show the highest rates.

About 12 months after Wendy started aggressive chemotherapy, imaging showed the tumour had shrunk. But the tumour also caused a blockage in her bile duct, which required a stent. When this became blocked, it caused an infection in her blood, and she was prescribed vancomycin.

The infection developed into sepsis, Penny said. The life-threatening condition results from the immune system's overreaction to fighting an infection. Wendy recovered.

"My mom was stable and she was out of ICU," Penny recalled. "She was deemed to be able to transfer back to Cranbrook, and I think this is where things started to fall apart."

Wendy was transferred back to East Kootenay Regional Hospital in Cranbrook on Feb. 25, 2023, and Penny joined her the next day. Wendy remained on IV vancomycin. 

Hospital staff drew a sample to identify what's called a key trough level, meaning the lowest concentration of vancomycin sinks to before the next dose.

The sample was taken just hours after a dose of vancomycin was given, "making it a peak level and impossible to draw conclusions," according to Interior Health, the health authority for the Cranbrook hospital.