The Invention of the Heart-Lung Machine Launches the Era of Open-Heart Surgery

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The Invention of the Heart-Lung Machine Launches the Era of Open-Heart Surgery

Overview

One of the most important advances in cardiac medicine in the twentieth century was the invention of the heart-lung machine. Scientists knew that delicate heart surgery was impossible without a console to take over the function of the human heart and lungs, but few deemed it possible. After decades of trial and error, John "Jack" H. Gibbon successfully tested the first human heart-lung machine in 1953, fueling the visions of his peers and ushering in a new era of open-heart surgery. Today, the heart-lung machine is an indispensable device that has extended the bounds of operative treatment beyond the most imaginative dreams.

Background

From the earliest days of medicine until the mid-1900s, tampering with the heart was considered taboo. For centuries, people regarded the human heart as the seat of our soul, our spirit, and our emotions, and as such the organ was off-limits to surgeons and doctors. Evidence of this belief is cemented in the writings of some of the earliest French surgeons. In 1648 Riolanus (a.k.a. Jean Riolan) described the heart as the "noblest organ in the body and the source of a life-giving substance which supplied the rest of the body with nourishment."

From the Middle Ages through the Renaissance, physicians observed heart functions and failure but did more to impede medical progress than to further it. With the exception of a few bold scientists, the heart remained surgically untouchable for two and a half more centuries.

Those who dared to suggest that heart surgery was, indeed, possible, were looked upon with doubt and disbelief by their peers. Heart wounds could be sutured and the cavity surrounding the heart could be drained, but little beyond these procedures found acceptance.

By the turn of the twentieth century, medical science was booming, and yet cardiac surgery remained virtually non-existent. Scientists had pioneered major advances in anesthesia, antibiotics, and blood transfusions, but successful surgery of the heart and chest was still decades away. Doctors carrying out experimental work in the early 1900s failed more often then they succeeded, and open-heart surgery remained an evasive pursuit.

In the early 1930s a young medical resident, touched by the death of a patient suffering from a pulmonary embolism, gave birth to an idea that he pursued vigorously for the next twenty years. John "Jack" H. Gibbon (1903-1973) proposed building a machine that would perform the function of the heart and lungs during surgery. Little did Gibbon know that his novel idea would one day revolutionize surgery of the heart.

While Gibbon struggled with various prototypes and experiments, World War II broke out. The need for improvements in cardiac surgery escalated with a fervor never seen before. Soldiers with shell fragments and bullets lodged inside their hearts begged for help as military physicians pondered how to save them. To do nothing was dangerous, but to remove the foreign objects was almost surely fatal.

One of the first surgeons to cut into a beating heart was Dr. Dwight Harken, a young U.S. Army surgeon stationed along the European front. Harken conducted three different animal studies to see if he could slice open a beating heart and remove the shrapnel with his own finger. His first experiment was a complete failure; all 14 animal subjects died. The second time, 7 died. But by the third test, only 2 of the 14 died. Harken was ready to try the technique on humans. He eventually removed 134 missiles from the chest, including 13 in the heart chambers, without losing a single patient. His success proved that human heart surgery was possible.

After Harken's incredible accomplishment, advances came one right after another. In 1948 doctors performed a bold procedure to widen a narrowed mitral heart valve, following the same finger-insertion procedure used by Harken. Early results were devastating and most-often fatal. Gradually, surgeons refined Harken's technique, and the mitral valve procedure became quite safe.

Despite the tremendous leap in cardiac surgery, the advancement made little difference to patients suffering from more serious heart problems, such as congenital heart disease. Surgeons could not open the human heart without fear of patients bleeding to death. While it was possible to temporarily halt a patient's circulation, doing so gave doctors only four short minutes to work magic before brain damage from oxygen deprivation would occur.

Then, a young Canadian surgeon suggested a highly bizarre, but quite plausible, solution. Taking a cue from hibernating animals, which survived the bitterly cold Canadian winters, Dr. Bill Bigelow theorized that cold temperatures might be the key to open heart surgery. Bigelow discovered that by cooling animals considerably, open-heart surgery could be performed for long periods without death. At hypothermic levels, the tissues of the body and brain required less oxygen and, therefore, could survive much longer.

Bigelow's discovery allowed physicians to embark on an exciting new level of cardiac surgery. Daring to push science to the limit, two University of Minnesota doctors attempted the first open-heart surgery in 1952. Drs. Walton Lillehei (1918- ) and John Lewis operated on a five-year-old girl who had been born with a hole in her heart. They cooled her body to 81 degrees Fahrenheit (27 degrees Celsius) and quickly repaired her injured heart. The child was immersed in warm bath water to raise her body temperature back to normal. The operation was a success.

While 10 minutes gave physicians enough time to treat small heart defects, it was insufficient for more complex problems. Doctors needed time to first visualize a major defect, and even more to repair it. Cardiac surgeons had hit a roadblock.

Gibbon had what they needed. After 23 years of trial and error, the Philadelphia native finally fulfilled the dreams of surgeons across the country. Gibbon built a machine that was successfully capable of assuming the functions of the human heart and lungs. The innovative and indispensable device was the result of more than two decades of hard labor and often discouraging results.

Gibbon's early experiments were cumbersome and dangerous; the machine often leaked blood, and hemorrhaging was a common form of failure. One of his first successes came when his heart-lung console proved capable to support the vital heart and lung functions in small animals during occlusion of their pulmonary artery. The results were very encouraging and further tests were planned. But Gibbon, now the director of surgical research at the Jefferson Medical College, lacked the funding and support to carry out such plans.

In a stroke of incredible luck, one of his medical students introduced him to Thomas Watson (1874-1956), the visionary chairman of International Business Machines (IBM). Watson agreed to underwrite the cost to develop a heart-lung device for human adults.

With money in his pocket, the aggressive Gibbon refused to let earlier complications discourage him. By January 1952 he was ready to test his machine on human patients. Gibbon announced his results at the May 1952 American Association for Thoracic Surgery: "I believe we are approaching the time when extracorporeal blood circuits of the heart-lung type can be safely employed in the treatment of human patients."

Gibbon had perfect timing. By the time of his 1952 speech, surgeons in a number of medical centers were constructing similar machines; three of them had used the machines in human cases. Gibbon believed his thoroughly tested console would safely permit precise, unhurried operations inside the human heart, and he vigorously sought to prove his point. Gibbon made certain his tests were performed on patients who would not have survived their ailments without surgical intervention.

Gibbon's first opportunities to use his machine on humans failed tragically. His first attempt was in March 1952 on a desperately ill 42-year-old man who had a possible clot or tumor in the right atrium. The outlook was bleak from the very beginning of the operation. The diagnosis was incorrect: neither a clot nor tumor was found. The patient's right ventricle was swollen to about twice its normal size. Doctors concluded nothing could be done and the procedure was terminated.

A year later Gibbon conducted the first trial with total cardiopulmonary bypass. The patient this time was a 15-month-old girl whom doctors believed had a heart defect. No such defect was found and the child's enlarged heart began to weaken from the moment it was exposed.

Three months after the tragic experience with the infant, Gibbon finally achieved success. The first successful open-heart surgery using cardiopulmonary bypass with the heart-lung machine took place on May 6, 1953, on a young woman with an atrial septal defect. The patient survived. News of Gibbon's success spread rapidly across the states. His dream had been realized and his accomplishment instantly made him a national and international celebrity.

Impact

A new era of heart surgery had begun. IBM began revising the original heart-lung machine, and other companies quickly followed suit. In 1955 John Kirklin at the Mayo Clinic reported success with a slightly modified Gibbon apparatus.

In the early 1960s scientists discovered that combining Gibbon's technique with the hypothermic cooling method originally proposed by Bigelow brought even better results. The method became known as extracorporeal cooling. The machine cooled the blood as it circulated through it, and after the operation, warmed it back to the correct temperature. With the heart dry and motionless, surgeons could operate more efficiently on the coronary arteries.

Gibbon and the earlier pioneers opened the door for cardiac surgery's exciting climax: organ transplantation. In 1967 South African surgeon Christiaan Barnard (1922- ) transplanted the first human heart. While Barnard's surgical triumph was short-lived, Dr. Norman Shumway was not discouraged. By the mid-1970s Shumway had devised a way of spotting rejection attacks and transformed the picture for heart transplant patients. In little over a half of century, the heart had been transformed from a forbidden organ to one that could remarkably be repaired, or even replaced.

By January 2000 261 medical institutions in the United States operated an organ transplant program. From 1988 to 1999 doctors performed more than 20,000 heart transplant surgeries in the United States.

KELLI A. MILLER