Canadian researchers say they have uncovered several potential errors that could dangerously undermine the production of chemotherapy solutions — and threaten “catastrophic” consequences for some of the thousands of cancer patients treated with the drugs daily.

The just-published findings by scientists who “embedded” themselves in hospital pharmacies are already triggering changes in the facilities, and are part of a broader investigation into chemo safety prompted by the overdose death of an Edmonton cancer patient.

The wider probe uncovered mistakes such as hooking up patients to the wrong infusion pump, delivering the drugs perilously quickly and failing to infuse the crucial chemical cocktail at all.

A report on those findings was produced two years ago, but has never been reported on publicly before.

The toxic nature of chemotherapy makes it particularly critical to avoid errors in its use, said Rachel White, the latest study’s lead author and a “human-factors” expert at Toronto’s University Health Network (UHN).

Dosing of chemotherapy and the timing is a really complicated balance

“It’s such a high-risk medication,” said Ms. White, a researcher with HumanEra, a UHN project that aims to find systemic problems behind medical blunders, estimated to cause thousands of deaths a year in Canada.

“You bombard the system with these drugs, trying to get as many bad cells as you can, but accepting that you’re also going to take out some of the good cells as well. So dosing of chemotherapy and the timing is a really complicated balance.”

Given how dangerous chemotherapy can be, the work of preparing treatments is often stressful, especially when numerous patients are awaiting their infusions, said Kathy Gesy, Saskatchewan’s provincial leader of oncology pharmacy services. The system has taken to heart, however, the findings and advice highlighted in the new study and other research, she said.

“In the last four or five years, there have been major changes in how we work, all focused on safety,” said Ms. Gesy.

The overhaul quietly taking place in Canadian oncology wards stems largely from that Edmonton death in 2006 and the “courageous” decision by Dr. Tony Fields, head of the city’s Cross Cancer Institute, to make the tragic mishap public, said Ms. White. Dr. Fields was one of the authors on the latest study, along with the UHN’s Dr. Anthony Easty.

The Cross centre’s 43-year-old patient died when her infusion pump was wrongly programmed and a potent dose of the drug fluorouracil surged into her body over four hours, instead of the intended four days. A subsequent report by the Institute for Safe Medication Practices uncovered evidence of at least seven other accidental, fluorouracil-related deaths in recent years, though it was unclear if any occurred in Canada.

Ms. White and other members of HumanEra were asked to review the whole process of administering chemotherapy.

Their report in 2011 included results of a survey of 331 doctors, nurses and pharmacists involved in cancer care, who reported over 230 adverse events involving chemotherapy, though it is possible different people cited some of the same incidents.

The problems included attaching the wrong infusion pump to a patient, incorrectly calculating the volume of drugs, and “numerous cases” of the pump being clamped shut so the patient absorbed none of the medication. There were also 67 reports of events reminiscent of the Edmonton accident, the pump malfunctioning so it delivered too much or too little medicine. One professional reported “at least two incidents where … infusers emptied much faster/sooner than they were supposed to and patients were very ill as a result.”

That report and others have already brought about significant change, said Ms. White, like extensive new training on operating the pumps, and use of pre-printed forms that make ordering the drugs clearer.

The study just published in the Journal of Oncology Pharmacy Practice stemmed from unique research that involved HumanEra scientists actually “embedding” themselves in the pharmacies at six hospitals across Canada and observing how work was done.

The team highlighted three serious flaws: The lack of a second worker in some pharmacies to check whether a chemotherapy solution had been properly combined; work surfaces where several bags of chemicals were being prepared at one time, raising the risk of mix-ups; and failing to keep a label bearing the patient’s name attached to the infusion bag at all times, increasing the chances of giving patients the wrong drugs. The study includes a photograph of a pharmacy technician with a jumble of prescriptions pinned to a board above his bench, with the corresponding bags below, not unlike a busy restaurant cook surveying dinner orders.

Once the bag leaves the pharmacy, though, no one would know a mistake had been made, the researchers note. They are launching a new study to analyze the contents of completed chemotherapy bags to determine how often they contain the wrong ingredients.

National Post