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Therac 25

In: Other Topics

Submitted By eboland2
Words 1684
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Part 1: Defend the AECL In the late 1900s, cancer treatment was reaching a whole new level with the Therac versions of radiation machines. These machines were able to target fast growing cancer cells and destroy them with x-rays and electromagnetic rays. Each new version of the machine contained major improvements for cancer treatments. However, with the release of the Therac-25 version came issues of over-exposure to radiation and deaths for already suffering cancer patients. There has since been a big debate about who is liable in the situation – The AECL, the hospitals, the operators, or the FDA. There are many reasons that the AECL, the creators of the Therac-25 machine, should not be liable for the injuries and deaths caused by the machines. First of all, consider the purpose of a person who works for a company or corporation. That is, to create and sell products that help the company make as much money as possible. The success or failure of that company depends on whether or not the products sell. Therefore, if a company produces a bad, unethical, or unsafe product, it is the job of the consumers to do their research and not purchase the product. It’s simple: if consumers don’t buy bad products, the company won’t be successful and continue selling them. The AECL did their job, which was to create a product that customers wanted to buy.
The second reason the AECL should not be liable is because they met all of the requirements of the third party company whose job was to protect the everyday citizens from harmful medical devices. The two major changes with the newer machine were the software, which newly required less time for machine set up and more computer control of safety, and the double pass accelerator, which was cheaper, more powerful, and more compact than previous versions. Both of these updates were built from the foundation of the previous Therac machine, which went through the rigorous testing required by the FDA. Therefore, the AECL met the FDA’s pre-market equivalence option and didn’t have to have rigorous testing performed on their machine. If their machine was able to pass all safety requirements from the FDA, whose main job was to protect customers, it makes sense that the AECL would get their product on the market as soon as they could, rather than spending more time on unnecessary testing. To further prove the innocence of the AECL, consider the liability of the other parties involved in the situation. First of all, looking back to my first point, the hospitals did not do their job as a consumer to properly and thoroughly research the product before making a huge investment in it. If they did do such research, then they completely disregarded blatant facts about the product. By doing a little bit of research, the hospitals could have easily found out that the FDA did not require any rigorous testing on the new medical devices that were built from the platform of an older, successful device. They would also recognize that the safety features of the machine had been completely rebuilt into the software rather than the hardware as it previously was, and those new software safety features had not gone through rigorous testing. Before any hospital introduces an incredibly powerful treatment device, they have the responsibility to ensure that it has passed an incredible amount of testing and know that it will not cause any unnecessary harm to its customers. Next, the FDA is liable in the situation for one very specific reason: they didn’t do their job. The sole purpose of the FDA is to keep the citizens safe from harmful products and medical devices. First of all, they did not require enough testing on a potentially deadly machine. It is understandable that the company would not be able to do rigorous testing on every single product upgrade that occurs. However, if a potentially dangerous product undergoes a significant change, it should be rigorously retested, especially when the safety features are entirely rebuilt. Secondly, the FDA didn’t require open communication about injuries that occurred when using the product. How could they do their job to protect citizens if they were oblivious to what was occurring with the products?
By looking further into each specific case, we discover that the operators of the machine are also liable for the injuries caused in specific cases. First of all, consider the case of Issac Dahl at the East Texas Cancer Center, who died from radiation over-exposure. In this case, the operator made a mistake entering system settings during treatment preparation time. She then tried to correct her error while the patient was underneath the radiation machine. The combination of buttons the operator pushed was what caused the injury. Also, she did not ensure that the audio and video monitors were properly set up before she began the treatment that day. If the proper precautions were taken to ensure they were working before treatment, she would have heard the patient screaming after he was hit with a radiation blast and stopped the treatment before a second one hit him. A similar incident happened to Daniel McCarthy four days later with the same operator. She made a mistake during treatment and tried to correct her error in the same way. Unfortunately, Daniel McCarthy also died. A product creator should not be responsible for predicting and preventing all mistakes that an operator could make with it. For example, car manufacturers cannot prevent car accidents; it is simply not possible. A car manufacturer would not be held responsible if its operator made a mistake. The same concept should be applied to the Therac-25 case. In conclusion, AECL is not liable for the accidents that the Therac-25 has been blamed for causing. The goal of a company or corporation is to make as much money as possible, and they should be allowed to work towards that goal, as long as they follow the requirements that the government sets out for them. In the end, it is the consumer’s decision whether or not to purchase and use their product, which determines the success of that company. The hospitals should have been much more careful in the products that they chose to buy to use on their customers. Also, the FDA should have had tighter requirements for new versions of products, especially if the safety features are rebuilt. And finally, in some of the cases, the issue began because the operator of the machine made a mistake. When you are in control of a potentially dangerous machine, you have to be very detailed and meticulous with the instructions you give it.

Part 2: My Personal Opinion

After careful consideration over who should truly be liable for the injuries and deaths that were blamed on the Therac-25, I believe that the hospital, the FDA, the AECL, and, sometimes, the operators all hold liability in the situation. The hospitals had a responsibility to prevent unnecessary harm to their patients. By not doing enough research on the machines before they purchased and used them on patients, the hospitals neglected their customers. It would have been rather easy to find out that the FDA did not require them to do extensive testing on the new safety features of the machines. The FDA is liable because it was their responsibility to keep citizens safe from unsafe medical devices. By not requiring reports to be given to them for each injury, they were neglecting a very crucial aspect of keeping people safe. Also, they should have had much stricter testing on the Therac-25 because there were significant changes to the software, especially the aspect of the computer controlling the safety locks.
The AECL is liable because they sent a life threatening machine into the market. Even as a Computer Science student, I am well aware of the extensive tested needed for computer software, even for smaller, simpler programs. There are often gaps in human logic that need to be worked out during the testing stages. I am shocked that software engineers wouldn’t extensively test software that has the potential to seriously harm and kill patients. The article mentions that the AECL did do Fault Tree Analysis on the machine, but they completely left the software out of that testing. Even though I extensively argued that they shouldn’t be liable because it is the responsibility of consumers to do research on what they buy, I do believe the AECL is liable. They did, after all, create and release the dangerous machine.
In the Isaac Dahl and Daniel McCarthy cases, the operator was also liable for the injuries and deaths of patients. The operator made a mistake when she was preparing the machine for its operations. The machine messed up only after she tried to correct her mistakes from afar. Operators of serious machines need to be very careful when they are setting them up.
I believe the health community can learn a lot from all of the mistakes that happened with the Therac-25 situation. If everybody learns their lessons, then this type of mistake can be prevented in the future. First of all, hospitals need to do extensive research on the products that they buy to treat patients with and the companies that create the products. This will keep unethical medical companies from continuously producing more bad machines. Secondly, the FDA needs to require stricter testing and narrow down the situations in which the pre-market equivalence idea can apply. If a machine’s safety features are rebuilt, for example, the machine needs to redo that testing. Third, software engineers need to better test their software themselves. Because they built the software, they are the people that understand it the best and would be the best people to test it. And finally, operators of these dangerous machines need to be much more meticulous and careful with the settings they enter. If all of these lessons are applied in the future, the possibility of injuries by such machines would decrease dramatically.

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