A Fatal Chemotherapy Error in Canada

Yesterday the results of two separate investigations into the death of a Canadian cancer patient were released. Both reports documented the mistakes made in the programming of a chemotherapy pump that was supposed to deliver a controlled infusion of fluorouracil over 96 hours:

On Tuesday, the Institute for Safe Medication Practices Canada released its independent report on the death of 43-year-old Denise Melanson last summer at Edmonton's Cross Cancer Institute.

A pump was supposed to deliver fluorouracil, a drug used to treat tumours, over four days, but it was given to Melanson over four hours, along with another chemotherapy drug, cisplatin.

A misprogrammed chemotherapy pump is a rare occurence. According to the news story there have been seven other similar incidences reported in North America, a disturbing yet small number of errors compared to the annual ouput for all of health care. Chemotherapy errors can occur from a miscalculation of dosage by the doctor or pharmacist, but typically they are the result of a breakdown in the communication or interpretation of the specific orders. This is the first I have ever heard of a pump being incorrectly programmed.

Melanson was undergoing treatment for naso-pharynx cancer, where the cavity of the throat and nose meet. She had already received radiation and chemotherapy. [Dr. Tony] Fields, the cancer board's vice-president of medical affairs and community oncology, said at the time of Melanson's death that her cancer was advanced but she was being treated with the expectation of a cure. He also said the the two nurses involved were experienced and highly trained, and there was no indication of negligence.

When oncologists finish calculating the proper doses of chemotherapy they document these numerical results either on paper or electronically. The orders are then read by the pharmacist and/or the oncology nurse specialist. The nurse then delivers the chemotherapy to the patient, usually intravenously. What went wrong in the death of Ms. Melanson?

The Institute for Safe Medication Practices identified 16 factors that led to the accidental overdose, including a complicated mathematical formula that tripped up two nurses administering her drugs.

According to the report, on July 31 a nurse made the initial error after she misunderstood a pharmacist's prescription and then misprogrammed the electronic pump to disperse fluorouracil, a drug used to treat tumours, over four hours instead of the prescribed four days, along with another chemotherapy drug, cisplatin.

A second nurse double-checked her work, but couldn't find a calculator and ended up doing the mathematical equation mentally and on a piece of paper. She didn't catch the mistake and the electronic pump was then given to Ms. Melanson.

As the only investigative medical oncologist/journalist on the ScienceBlogs website (Orac is a surgeon, you know), it is my duty to translate the medical facts of this case into plain English. Ms. Melanson had advanced stage nasopharyngeal carcinoma, (probably stage IV since earlier stages are typically treated successfully with radiation therapy only). Nasopharyngeal carcinoma is a rare and aggressive tumor that is endemic in southern China and Southeast Asia and is associated with exposure to the Epstein-Barr virus or consumption of Cantonese salted fish (which is rich in nitrosamines). Based on the results of an American clinical trial the standard treatment in North America is to give concurrent radiation therapy and cisplatin chemotherapy, followed by three more cycles of cisplatin and 96-hour infusional fluorouracil, each cycle given three weeks apart.

If one treats a patient of average body surface area (1.73 meters squared, or m2), the calculated dose of infusional fluorouracil in this regimen would be 1000mg/m2 X 1.73 X 4 (days) or 6920 mg given over 96 hours.

The standard daily dose of fluorouracil given as an intravenous push is 500mg/m2, which would produce a daily dose of only 865 mg. This daily dose can be repeated up to five days in a row, which adds up to a maximum dose of 4325 mg given over 120 hours.

Therefore assuming she had a standard body surface area, Ms. Melanson received 6920 mg of fluorouracil over four hours. The following day she was told that she had received a lethal dose of chemotherapy. She died 22 days later when artificial life-support was withdrawn.

Ms. Melanson, a Nova Scotia native who moved with her family to Alberta in 2005, took the "high road" after she was told about the overdose and the fact there was no cure.

"There was little room in her heart for bitterness and anger."

Next: How Do Oncologists Prevent Errors in Dosing? A Highly Biased Opinion from Yours Truly

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I cried - we all cry.
A tragedy for everyone involved.
How are they to pick up the pieces?

Wow, that's just awful.

Not knowing anything about fluorouracil (and not wanting to sound morbid) what happened to this woman? She was told she received a lethal dose of chemotherapy, so what happened physiologically? How did she die, how quickly would this have shut down her body? How many conscious days did she have?

It's awful that there's nothing that could be done.

I hope whatever hurry these folks were in that they couldn't stop and track down a calculator was really important.

The thought just leaves me cold and sad. As a patient, I want to know that I am safe. But the reality is that even in the clinical setting we are subject to the same forces of humaness that we are everywhere else. To demand that the nurses and doctors and pharmasist be without error is, well, just plain stupid. They are human and they are going to make errors. They did what they could to try to prevent this by checking each other. It is tragic that the error wasn't found. It must have been horrendous for them when they realized the error. It must have been horrendous for the person who had to tell her of the mistake. I have mental blocks against being able to try to fathom the pain she and her family and friends went through because of the mistake. Still, it is wrong to stand back months later and try to pass judgement on the nurses involved. They are human and humans make errors. I would only pray in the same situation I'd be able to express forgiveness to them.

It seems too easy to sit back months later and pass judgement on the nurses involved, especially when you weren't in the moment with them and you have no idea what the pressures were that there at that moment. Things don't happen in the vaccuum of hindsite, they happen in real life and the vaccuum can't be observed after the fact. To expect the nurses to be anything other than capable of human error is ludicrous. You might as well ask the sun to quit being hot. The nurses' checked each other and in a perfect world that would have been enough to prevent any error. But this is not a perfect world and the system works well enough to make this sad situation such a rarety that we are all gasping and blogging about it. It must have been a life and career changing tragedy for the nurses to have realized their mistake and horrendous for the person who had to tell Ms. Melanson of the error.

As patient I still feel safe (as safe as you can feel knowing that you are being poisoned) in treatment. I would only pray that if given the same situation I'd be able to express forgiveness to the people involved and die in peace as it seems Ms. Melanson has. What would be the gain of anything else?

I've been thinking about this sad occurance all day, and I've got a few questions, hopefully not out-of-bounds:

1. I imagine that the nurses had knowledge of what were the usual dosages of the chemotherapy drugs that they administer. Is it possible that they might have noticed beforehand that they were giving a high amount of the drug over a short period of time, something that would have stood out as unusual? Or is there such a variation in the dosages of chemotherapy drugs, that the dosage used in this case would not have drawn a red flag?

2. Is a patient informed in writing by their doctor exactly what chemotherapy drugs they will be getting at each session, in what amounts and over how many hours, and also told to bring that written information to each session? I'm just asking, because I'm wondering what info Mrs. Melenson had about her treatments, if she was aware that the drug was to be administered over 4 days, not 4 hours. Would a nurse doublecheck with a patient about each individual treatment, to make certain things add up, or is this not done, for any variety of reasons?

I have to say that I'm glad that the doctors noticed the mistake early on, and were honest with Mrs. Melanson and her family.

Nurses were criminally negligent and should have been sentenced to the same penalty as a drunk driver who kills.
Actually they should receive stiffer sentence because they are held to a higher standard than a worthless drunk.

Of course we're all human. That is why there has to be a process in place to protect our patients from human error. The nurse checking the pump is responsible for making her own calculations, and manually is not acceptable. Did she calculate and come to the same wrong conclusion, or did she attempt her calculation while looking at what the pump was programmed at by the first nurse? Even mentioning that she couldn't find a calculator shows lack of professionalism and I would not want that person administering my chemotherapy. I do administer chemotherapy and the best director of nursing I have ever worked for taught me that every error needed to result in a process correction so that it could not happen again. Now if a process is in place and is not followed by the employee, education, and disciplinary action are required. Educating the patients also protects them. There is no reason not to inform them of how many ml's will be given in a 24 hr period, etc. The patient would have caught the error had they been told how much was to go in over 2 days, if they looked at the rate on the pump they would have pointed out it was wrong! Not that patients should have to check, but I would and recommend giving patients as much information as possible to ensure their safety. Have a careful process in place that will not be circumvented no matter how "busy" you are. My prayers to the family and all involved. Please know that this will be passed on so we can all stop and learn and maybe someone else was helped by you're sharing.

By Patti Belzunce (not verified) on 21 Jan 2008 #permalink

I hope whatever hurry these folks were in that they couldn't stop and track down a calculator was really important....