Medical Students: Not Tested on Animals

In recent years, a number of medical schools have changed the way they train students to perform surgery. Whereas medical students previously received surgical experience on animals before moving on to human patients, the use of animals in these schools has been quietly dropped. Now the first surgical experience students at such schools get is when they operate on a human patient. Given that such a change in training affects us all, it is important to examine its consequences.

For generations, all medical students were required to take a laboratory course in medical physiology that involved hands-on experience with living animals. The course typically began with the study of basic physiology in animals such as frogs, turtles and rabbits. It then moved on to the intensive study of physiology using dogs, which were usually obtained from a pound.

It was in the "dog labs" that students learned the basic techniques of surgery they would later apply to humans. And there were many techniques to learn. First, it was necessary to anesthetize the animal and students soon became accomplished in the intravenous injection of anesthetic solutions (for the animals were never allowed to feel any pain). Next, the animal was placed on a respirator and the technique of inserting a breathing tube into the trachea was mastered. When it came time to operate, students tended to underestimate how hard they needed to press with a scalpel and skin incisions in early surgeries were usually imprecise and bloody. Over time, students learned to make neat and precisely placed incisions with a minimum number of strokes. But the most important aspect of training was yet to come, one that no anatomical model or computer program can duplicate, and that was the control of bleeding.

The key to successful surgery is quite simple; it's the control of bleeding – hemostasis. Obviously, uncontrolled bleeding can be life-threatening to the patient if the amount of blood loss becomes too great. However, even a small amount of bleeding can be a serious problem. This is because blood can obscure the surgical field making it difficult for the surgeon to see what he or she is doing. When this happens, it reduces the precision with which the surgeon operates and lengthens the time it takes to complete the surgery.

The way one learns to minimize surgical bleeding is the same way that any complex skill is mastered – through practice. This was exemplified by my own training in neuroscience in which I learned to perform animal neurosurgery under the direct supervision of an experienced neurosurgeon. The first few surgeries that I conducted, although considered satisfactory, were accompanied by a small amount of bleeding, not enough to be life-threatening, but they obscured the surgical field making it difficult to see exactly what I was doing. However, I can still remember the first time I conducted an operation that was virtually bloodless – from start to finish the surgical field was clear and from that time on virtually all those surgeries were equally bloodless. Can I explain what was I doing differently? The answer to that question is no. Learning surgery is much like learning how to ride a bicycle or play a musical instrument; while explanations and demonstrations are necessary, ultimately you must learn by doing. And the skills one acquires in performing animal surgery transfer to operating on humans – don't let anyone tell you differently.

In addition, working with animals allowed me to experiment with new techniques. For example, I had been taught always to tie off blood vessels that crossed areas in which I was operating because to go under them was to risk breaking them. However, I was reluctant to tie them off as this reduced the blood flow to other parts of the brain, which could only have a detrimental effect, and so I attempted to operate beneath them. Not surprisingly, my first attempt broke the blood vessel and I had to tie it off. But on the next attempt I found that I was able to operate under major blood vessels without breaking them, a technique that reduced the general trauma to the brain and became my standard procedure. Without access to animals, however, human surgeons can only improve their techniques by experimenting on their patients – whether to take such risks with patients is a personal decision.

The reason the use of animals in medical training is being abandoned, of course, is because of the animal rights movement. The main impact of these groups has not been through public protests, but though lobbying efforts which have resulted in extensive changes in the Federal Animal Welfare Act and its enforcement by the USDA. By making it a law that the use of animals for teaching or research should be minimized, the Federal government has stigmatized such use as being morally wrong. Moreover, the practical effect of the Animal Welfare Act has been to greatly increase the cost of using animals in both the amount of effort it takes to obtain permission to use animals as well as the cost of acquiring and housing them. When faced with such costs, as well as demands from some students who claim moral objections (and are then rewarded with a reduced course of study that omits animal labs) even the most dedicated teacher eventually gives in.

So we have reached the point at which it is considered immoral for surgery to be taught using animals, but perfectly acceptable to use human patients, none of whom are aware that they are being used for training. For when you go in for surgery, you routinely sign a consent form that allows the surgeon to let others operate on you. It is ironic that these forms often contain a clause that allows you specify whether tissue removed from your body during surgery may be used for future training, while you are given no say in whether you yourself may be put to such use.

Fortunately, the solution to this problem is within reach of anybody considering surgery. If you wish for the surgeons who will be operating on you or your child to have a particular level of skill, then write it in on the surgical consent form, which is, after all, a legally binding contract. For example, you may specify that anyone participating in the surgery be board certified or that they have previously conducted a minimum number of similar operations. Alternatively, you might volunteer to allow a student whose only surgical experience has been on animals to participate in the surgery, at a reduced price to you of course. And if you object to the use of animals for medical training, then you can request that students who are complete novices be allowed to participate in your surgery thereby personally reducing the demand for animals in medicine.

But most importantly, the Federal government must get out of the business of legislating morality as its attempts to do so result in contradictions. For example, the government finds it necessary to send troops into battle all over the world, yet has forbidden military surgeons to use animals to learn how to treat gunshot wounds. Similarly, the idea, embodied in the Animal Welfare Act, that the use of animals in teaching and research is morally wrong and should be minimized, and eventually eliminated, makes no sense. If it is true that using animals for our benefit is immoral, then the Federal government should also regulate our consumption of animal protein and outlaw foods, such as double cheeseburgers, that contain more than the minimum protein requirements.

Some legislators have recognized that increasing the regulation of animals in research and medical training may have its drawbacks. Thus, the recently passed Farm Bill contains an amendment that prevents the extension of USDA regulations to rats, mice and birds. While this is a step in the right direction, what is needed is a thorough examination of the effects of current regulations on both medical training and research – regulations that have resulted in human patients being used without their consent as replacements for animals in surgical training.

July 15, 2002

Dr. Henry Heffner [send him mail] is professor of psychology at the University of Toledo. Visit his webpage.

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