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Medical Research Modernization Committee

The True History of Medical Progress



by Dr. Ray Greek



Director of the



Medical Research Modernization Committee



INTRODUCTION



Why do we experiment on animals? Are they just funny looking people

with exactly the same organ tissues and diseases we have? When did all

this start?

In the first century, the Church prohibited performing autopsies on

humans. So, the scientists did what they thought was the next best

thing. Scientists like Galen dissected animals and applied his results

to humans. Galen was wrong in many of the conclusions he derived from

animal experiments. In fact, animal experiments led scientists astray

for centuries. Galen thought that the "heart was a warming machine for

two separate types of blood. He was convinced veins and arteries were

not connected and blood flowed both backward and forward from the

heart." Historians have said this about Galen:

"based mainly on the study of apes and pigs, and he unhesitatingly

transferred his discoveries to human anatomy, thus perpetuating many

errors."

This misinformation lasted for centuries. Unfortunately, we have not

progressed as far as some people think. We are still experimenting on

animals, despite the fact that better techniques are available.

The first big step for medical discoveries was during the Renaissance

when the Italian scientists and artists began to perform autopsies on

humans. This corrected many of Galen's errors. Vesalius was condemned

to death by the Church and had to hide because his discoveries

disproved Galen's theories. The Church had adopted Galen's positions

and was reluctant to change. Much as the scientific community of today

is reluctant to accept progress.

During the 19th century, many discoveries were made because of human

experiments. Harvey described the circulation of the blood. Many have

tried to credit Harvey's discovery to animal experiments (or

vivisection). Lawson Tait, a famous nineteenth century surgeon, had a

rather different impression of this part of medical history. He

stated:

"That he [Harvey] made any contribution to the facts of the case

[blood circulation] by vivisection is conclusively disprovedIt is,

moreover, perfectly clear that were it incumbent on anyone to prove

the circulation of the blood as a new theme, it could not be done by

any vivisectional process but could, at once, be satisfactorily

established by a dead body and an injecting syringe."

Medical discoveries were rampant during the 19th century. The

stethoscope, blood pressure manometer, microscopes and a host of

others were all discovered without animal experiments. This had not

dissuaded people who earn their livelihood from making the claim that

animal experiments were vital to these discoveries. If you made your

livelihood off experimenting on animals, you would have a vested

interest in saying the same thing.

Animal experiments really took off in the 19th century, largely due to

the efforts of Claude Bernard. He had this to say about laboratory

experiments on animals:

"Experiments on animals, with deleterious substances or in harmful

circumstances, are very useful and entirely conclusive for the

toxicity and hygiene of man. Investigations of medicinal or of toxic

substances also are wholly applicable to man from the therapeutic

point of view; for as I have shown, the effects of these substances

are the same on man as on animals, save for difference in degree."

"I consider hospitals only as the entrance to scientific medicine;

they are the first field of observation which a physician enters; but

the true sanctuary of medical science is a laboratory; only there will

he seek explanations of life in the normal and pathological states by

means of experimental analysis. "In leaving the hospital, a

physicianmust go on into his laboratory; and there, by experiments on

animals, he will account for what he has observed in his patients,

whether about the actions of drugs or about the origin of

morbid lesions in organs and tissues. There, in a word, he will

achieve true medical science."

That is an amazing statement. Animals are more like humans than

humans. Unfortunately for patients today, scientists still believe the

preposterous words of this man.

SURGICAL ADVANCES



Would you want a surgeon to operate on you if he or she had never

performed the procedure on humans? How about if the operation had only

been done on dogs? Do you think surgery residents should watch their

teachers perform operations and then very gradually be allowed to help

with the operation until finally they are able to do the entire

procedure under supervision or should they practice on animals and

then on you? How were all the surgical advances discovered and how do

physicians learn to be surgeons? Is modern surgery the result of

animal experimentation or human clinical observation? Have

technological discoveries or animal experiments led to the great

advances in surgery? What have animal experiments done for the field

of surgery?

Surgery would not be possible without anesthesia. Indeed, anesthesia

is one of the contributions to the history of medicine from the United

States. Physicians discovered the properties of anesthetics while

having so-called ether parties in the 1800's. Participants noticed

that while inhaling the substances, they became insensitive to pain.

Thus, the field of anesthesiology was born. Anesthesiology and

infectious control allowed surgery to advance out of the dark ages.

Many famous surgeons of the 19th and 20th centuries opposed animal

experimentation for surgery. Lawson Tait stated that animal

experimentation should be stopped "so the energy and skill of

scientific investigators could be directed into better and safer

channels." Tait stated that he had been led astray time and time again

by animal experiments. He believed vivisection wrong because of

misleading results and because focus was diverted from more reliable

data. Dr. Charles Mayo, of the famous Mayo Clinic, stated:

"I abhor vivisection. It should at least be curbed. Better, it should

be abolished...I know of no discovery that could not have been

obtained without it...."

Sir Frederick Treves stated about performing surgery on dogs,

"my experiments had done little but unfit me to operate with the human

intestine."

The differences between human anatomy and physiology were again cited

by president of the Royal College of Surgeons, Dr. Moynihan who

stated, "Has not the contribution of the laboratory to surgery of the

stomach, for example, been almost negligible when it has not been

potentially dangerous because divergent from human experience and

therefore inapplicable."

Perhaps the most important surgical advances have resulted from new

technology. CT scans, MRI's, ultrasound and other technologies allow

quicker and more accurate diagnosis of disease. Technological

contribution does not stop with the diagnosis however. New sutures

have been developed which allow very small incisions in the eye, heart

and other tissue. Microscopes which allow surgeons to reattach severed

fingers, hands and arms, have revolutionized surgery and saved many

people from devastating injuries. The microscope is also used for the

common procedure of placing tubes in a child's ears in order to

decrease ear infections and hearing loss. Microscopic discectomy, the

removal of a herniated disc in the back is accomplished with the

microscope. The microscope is also used in neurosurgery to allow very

small precise cuts of tumors off nerves. The development of the

stapler has done away with sutures in some operations. Making for a

better closure and quicker operating time. Lasers now allow

ophthalmologists to correct potentially blinding conditions without

anesthesia and as on an outpatient basis. Lasers are also used in

removing birth marks from the face and aid in stanching blood flow

during liver transplant surgery.

One advance in technology which has saved many patients from surgery

and from death is the endoscope. These instruments are commonly used

in order to visualize the inner colon, looking for early cancers. They

are also used in the upper GI tract to look for cancer and ulcers.

Prior to this patients were forced to swallow or have placed via an

enema, a chalk like substance which did not always provide adequate

visualization. Many procedures which would have required a major

surgery can now be performed non-surgically via endoscope. Along the

same lines of viewing without cutting, many operations are now

performed as laparoscopic procedures. Appendectomy, cholecystectomy,

hysterectomy, hernia repair and others were once only possible with a

large incision and a prolonged recovery. Laparoscopes allow surgeons

to make several very small incisions thus decreasing the likelihood of

infection and other complications and decreasing recovery time.

As more and more technology became available, more specialized

training was needed in order to use it. General surgery divided in to

neurosurgery, urological surgery, ophthalmology, otorhinolaryngology,

plastics, orthopedics, vascular, thoracic, cardiac, transplant surgery

and other sub specialties. This led to even more knowledge and further

technological refinements. The invention of the ophthalmoscope in 1851

allowed physicians to see inside the eye for the first time. The

otoscope, in 1860, allowed visualization inside the ear and the

laryngoscope in 1874, allowed better visualization of the larynx. The

ability to look at tissue under a microscope utilizing certain stains

and dyes allowed surgeons to decide whether or not to remove tissue or

treat more conservatively. Tissue implants including artificial eyes,

heart valves, penile prosthesis, skin expanders used in order to

harvest more skin for skin grafts, artificial blood vessels,

pacemakers and other advances came to us via technology not

animal research.

The field of neurosurgery owes much to advances in radiology. The

ability to actually see inside the nervous system and thus find

exactly where the problem lay was the sticking point in neurosurgery

for decades. Better diagnostic techniques such as myelography,

angiography and MRI scanners, has revolutionized the field. One of the

first neurosurgeons was Harvey Cushing of Boston, who developed many

techniques and instruments. The concept of using electricity to

coagulate bleeding vessels was Cushing's idea. The old method of

sewing each individual vessel when it was bleeding was time consuming

and imprecise. Today virtually no operation is performed without

electrocautery.

Other technical advances involving the microscope has allowed much

more pin point resection of tumors and lesions. This quote from Paul

Carrao, MD a former animal experimenter in head trauma exemplifies the

animal model dilemma:

"I just know what the literature shows, and I know what our results

were, and I challenge anybody to show that any of that[animal

research] has advanced the cause of the treatment of human head injury

one iota. The bulk of the knowledge that now exists and upon which the

treatment of head injuries is predicated is that which has been

derived from head injuries in the past, whether in the civilian sector

or in the military. In many ways the results which were obtained with

animals have been misleading, because in the case of quadrupeds, the

physiological mechanisms are different, so that the kinds of data

obtained from different systems - circulatory, the blood pressure and

so forth, respiratory, the cardiac - are different from those obtained

from human head injuries."

One example of animal experimentation misleading surgeons is the

operation called Radial Keratotomy. This operation is performed in

order to enable patients to see better without glasses. The procedure

was initially performed on rabbits. But it blinded the first humans.

The problem was that the rabbit cornea is able to regenerate on the

underside. The human cornea can only do this on the surface. Surgery

now performed only on the surface.

Thomas Starzl of Pittsburgh has been transplanting organs from animal

to humans for years. Starzl started by experimenting in the laboratory

for years and in the 1990s began to experiment on humans. He stated

that baboon liver transplants would be viable in humans in part

because baboons were resistant to hepatitis , a common cause of liver

failure and thus the need for a new liver. It was hoped that the

baboon liver would be resistant to the disease which infected the

patient. If the baboon liver functioned properly perhaps the patient

would not re-infect himself with the hepatitis. However even Starzl

admitted that, "a baboon liver could impose on a human recipient

lethal interspecies metabolic differences."

Others were not so optimistic. An advocate of xenotransplantation at

Harvard, Dr. Hugh Auchincloss stated, "survival rates reported for

allotransplantation (human to human) in those patients with hepatitis

B is superior to that which we could expect from xenotransplantation."

At autopsy, Starzls' transplanted baboon livers proved to be carrying

hepatitis. Of interest is the fact that Dr. Auchincloss also stated

that,"successful rodent experiments do not make an adequate scientific

basis for human experimentation."

Two baboon liver transplants were performed in 1993. One died within 4

weeks and the other 10 weeks. The quality of life during the time the

patients were alive was not something anyone would desire. Life in the

intensive care unit, unable to eat, walk, drink eliminate or even

breathe without constant mechanical assistance is not a decent quality

of life. The first baboon liver was infected with CMV, Simian Agent 8,

H.Papio and other diseases. Thomas Starzl of the University of

Pittsburgh has received over $8,000,000.00 in public funding in order

to experiment on baboons for xenotransplants. None have so far been

successful. Dr. Starzl expressed his contempt for preventative

measures when stated that he had a "cure for alcoholism" referring to

liver transplants.

Approximately 4,000 viruses have been identified which occur in

humans, animals, plants, and other organisms. Many of these can be

transmitted from xenotransplants (animal to human transplants).

Hepadnavirus, papillomavirus, retrovirus, aterivirus, togavirus,

adenovirus, parvovirus, hantavirus, papovavirus, and others can cross

over to humans, under the right circumstances. Some scientists also

postulate that Hepatitis B may have come to humans from chimpanzees.

Chimps harbor the virus asymptotically.

The idea of species contamination is not new. Millions of doses of

polio vaccine were infected with SV40. This virus causes cancer in

humans. The Marburg virus, from monkeys, killed 7 people in 1967. The

clinical manifestations of the virus caused physicians in Germany to

describe their patients as having "blood pouring from all apertures."

The patients became demented, went into coma, and eventually died

secondary to heart failure. The survivors did not fare much better.

Chronic liver failure, impotence and insanity were long term

sequellae. HTLV-2 may have originated as STLV in monkeys. The disease

causes leukemia in humans. Jacob-Cruetzfeld can cross from sheep and

cows and other animals to humans. This is the virus that has been

associated with "mad cow disease" in Great Britain. Rodent

hantaviruses can spread from rodents to humans. Monkey pox,

elephantiasis, yellow fever, tuberculosis and other diseases have been

documented to spread from animals to humans.

The macaque herpes B virus leads to brain infections in humans. It

is benign in monkeys. Scientists are now experimenting with pigs

because they do not believe pigs harbor deadly Ebola like viruses.

However, pigs do harbor pseudorabies, leptospirosis, erysipelas, wabah

babi, and others. The important question regarding any animal donor is

"what does it harbor that we do not know about?" New viruses are being

discovered in animals on a regular basis. Some of them do not harm the

host animal, but can be deadly for humans. Fortunately for the human

race, the viruses stay where they belong unless we disturb them.

Remember in the movie Jurassic Park when the character played by Jeff

Goldblum told the creator of Jurassic Park that "Nature finds a way."

We do not know as much as mother nature. We like to think we do, but

we don't. The public health implications of another retrovirus which

could mutate and be passed along like the common cold are

devastastating.

Arguably the invention to most change the face of medicine in the 20th

century was the cardiopulmonary bypass (CPB) machine. Dr. Gibbon's

machine was in part based on animal experiments. This was in part

responsible for the initial failure of the machine. Two out of 3 of

Gibbon's first patients died as a result of the heart-lung machine.

When the machine was revised based on studies of humans by Andresen,

the success rate increased. Andresen studied human circulation and

contributed the low flow theory of circulation to science. This is

when the blood volume is reduced in order for the patient to be

successfully connected to the heart lung machine. It was this human

data which allowed the CPB machine to be successful on humans.

Consider this statement from one of the inventors of modern

cardiopulmonary bypass:

"Biomedical research does not need animals any more, but should use

computers. It is pointless and even dangerous to continue following

the traditional paths, for the differences between man and animals is

so great that it mostly leads us into error. Artificial heart valves,

for example, and also the pacemaker for the heart, were first tested

on humans and only later was it established that they also function if

they are implanted in animals."

The correction of the congenital heart anomaly called Tetrology of

Fallot (TOF) is frequently cited to justify spending money on more

animal research. TOF is one of the causes of "blue babies." A Blue

baby is one who does not have enough oxygen in the blood to provide

the healthy pink color to the skin. The blood is bypassing the lungs,

thus not receiving the oxygen. A malformation of the heart usually,

does not allow blood to circulate normally. The whole story can be

found in Dr. Taussig's memoirs and textbooks of medical history.

Cardiologist Helen Taussig suggested a surgical correction of the

problem to Alfred Blalock, a surgeon. She based her suggestion on

autopsy findings on the affected infants.

Dr. Blalock attempted the procedure on dogs with poor results. Instead

of using animals with heart defects they cut lung tissue out of dogs

in an attempt to mimic the naturally occurring disease. Tetrology of

Fallot does occur in dogs, especially Keeshonds, but it is rare. So

the animal model was fundamentally flawed from the start. Dr.

Blalock's experience led him to state to Dr. Taussig, "The experiments

are suggestive but not very conclusive. But if you are convinced the

operation will work, I am convinced I know how to do it."

Dr. Blalock had in fact not been successful performing the procedure

in dogs. He thought it could be done in humans based on Dr. Taussig's

experience and based on his surgical experience. Contrast his

statement with this statement from those promoting animal research,

"The (animal) experiments were so successful and confirmed Dr.

Taussig's theory so completely that Blalock felt he could venture to

operate on one of the poor children."(Hugo Glaser, The Miracle of

Heart Surgery, London, Lutterworth Press, 1961, p59).

This is where the statement, "Which would you rather save one blue

baby or one brown dog?" comes from. It is not based on historical fact

but rather someone's wishful thinking. Sloppy thinking such as

exemplified by the above lead one surgeon to state,"The abolition of

vivisection would in no way halt medical progress, just the opposite

is the case. All the sound medical knowledge of today stems from

observations carried out on human beings. No surgeon can gain least

knowledge from experiments on animals, and all the great surgeons of

the past and of the present day are in agreement on that."

The development of the artificial heart valve, which has helped tens

of thousands of people was delayed secondary to research in dogs. Dogs

proved to be very good at making blood clots around the new valve. The

blood clots could lead to stoke or pulmonary embolism or other

complications in humans. Therefore, researchers would not release it

to humans. Many people died as a result of the new valves not being

available. The entire reason the valves were not released was based on

a myth. Dogs and humans do not clot in the same way. Humans did not

have the same problem with the valves and many people have the

artificial valves implanted each year. Some valves do require

anti-coagulants to avoid the complications, but this was not the

pointed out by the dog experiments.

What would happen if we did indeed abolish surgical training and

experimentation on animals? Researchers at Tulane University have at

least partially addressed this question. They examined complication

rates for the then relatively new procedure of laparoscopic

cholecystectomy. They compared the complication rate of those who

practiced on animals with those who did not. They found no difference

between the groups. Another area where animals are routinely used is

in training physicians to handle major trauma. Advanced Trauma Life

Support (ATLS) courses are costly in part because of the cost of the

animals. One hospital in Georgia decreased cost by 50% by eliminating

dogs from the course. Human cadavers were used instead. The

participants evaluated the course as equal or better than courses

using dogs.

More recent studies have revealed the physicians taking ATLS prefer

human cadavers to animals. This is not surprising. If you operate on

humans it only makes sense to learn on cadavers. Dr. Salvatore Rocca

Rossetti, surgeon and Professor of Urology at the University of Turin,

Italy, states that, "Nobody has become a surgeon because of having

operated on animals. He has only learnt wrongly through animals. I

have been able to see this over my many decades as a surgeon, also as

a Director of hospitals. I have carried out tens of thousands of

operations on people without ever performing them first on an animal."

Dr. Werner Hartinger of Germany agrees:

"The claim, frequently heard, that animal experimentation is vital for

the training of surgeons and that practice on living animals is

necessary to gain manual and operating skills cannot be left

unchallenged. A surgeon acquires his basic knowledge by observing and

then assisting his teacher. In time, according to his experience,

ability and manual dexterity he participates in supervised operating

duties, until the surgeon responsible for his training, decides as to

when he can start operating on his own. Specialized knowledge of

microsurgery is gained in the same way, just as working at the

surgical microscope does not call for operating on animals."
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