General Articles

BY-PASS TO LIFE

Every blue baby was doomed to a losing battle for oxygen until a surgical miracle found a detour past the road block in its heart

DR. W. W. BAUER December 1 1947
General Articles

BY-PASS TO LIFE

Every blue baby was doomed to a losing battle for oxygen until a surgical miracle found a detour past the road block in its heart

DR. W. W. BAUER December 1 1947

BY-PASS TO LIFE

Every blue baby was doomed to a losing battle for oxygen until a surgical miracle found a detour past the road block in its heart

DR. W. W. BAUER

THE ANXIOUS young mother brought her new baby to the hospital for examination. He was under normal size and weight, his development had been slow. His color, instead of rosy-pink, was bluish when he lay still, obviously blue when he cried.

The doctors detected unusual sounds in his heart. The X-ray shadow of his heart showed the presence of a defect in the artery which was supposed to carry blood to the lungs.

Though there was little the doctors could do, the boy grew to be six years old. By then he was thin, undernourished, blue and breathless after the least exertion. His lips were purple. His toes and fingers were bluish and showed evidence of enlargement known as “clubbing.” The diagnosis, in nonmedical terms, was—a blue baby.

Up to 1945 this boy would have been condemned to death by lack of medical knowledge.

Today, however, he is a happy, healthy, normal child. He was one of the first three successful cases reported after operation by Doctors Alfred Blalock and Helen Taussig of Johns Hopkins University, Baltimore.

While Dr. Blalock performed the first blue-baby operations in the United States, Dr. Gordon Murray of Toronto has carried the incredibly delicate surgery to a point of a near miracle. To date, in Toronto hospitals, he has operated on over 80 blue babies, with the extremely low mortality rate of seven per cent.

World Mecca

FOR MORE than 12 years the Canadian doctor has worked on experimental blood-vessel surgery and its clinical applications. What ultimately enabled him to perform the minute blood-vessel operations necessary to save blue babies, was the discovery of heparin. This is a substance which prevents clotting of blood, a fatal danger in former operations.

Parents all over the world have found a new Mecca of hope in Toronto. Dr. Murray receives letters weekly from every continent of the globe. Patients have come from as far as Sweden, France and England as well as the United States. In practically all cases there has been a happy ending to the pilgrimage.

Other doctors recommend a visit to Toronto, too. There was a Scottish war bride, Mrs. Ephriam Horton of Fonthill who, greatly troubled about her baby, consulted a doctor in Inverness. He was full of hope.

“If you can possibly make it,” he advised, “go to Toronto when you reach Canada. There’s a doctor there who has operated on blue babies. That’s your child’s only chance.”

Today two-year-old Anne Horton, in her Canadian home, is a well baby, thanks to Dr. Murray.

The tragedy of a blue baby has again and again aroused townships, villages and neighborhoods into kindly co-operation to finance the lifesaving operation. Dr. Murray himself, in many cases where payment was impossible, has given his services free.

What is a blue baby? And what is the nature of the now-famous operation which has restored so many such children to

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health and given them a chance of normal life?

In simplest terms, a blue baby occurs when the child’s blood cannot flow along normal channels into the lungs to be reoxygenized. The intricate surgery involved in trying to save a blue baby opens a by-pass beyond the; spot where the blood is bottlenecked. It is like a new traffic artery through which the blood can reach the lungs.

The human body operates not unlike an internal combustion engine. Ils fuel is derived from the food we eat, but this cannot be “burned” and its energy released without the presence of oxygen. The blood carries both fuel and oxygen to the muscles and other parts of the body where the actual combustion occurs and by the time it returns to the heart its oxygen is exhausted. It must be pumped through the lungs again and the blue

“venous blood” reoxvgenized so that it is again a healthy red as it begins another circuit through the body. It is the heart that does the pumping and actually it is a double pump; the blue blood returns to the right chamber, or ventricle, which pumps it through the pulmonary artery through the lungs, after which it enters the heart’s left ventricle and is pumped back through the body.

Some infants are born with a defect in this system—the pulmonary artery ! which should carry the blood from the heart to the lungs is much too small. Only a trickle of blood passes through to become reoxygenized and thus barely enough energy is generated to sustain life.

Emergency Route

Obviously, the blue blood which flows into the right ventricle from the body must go somewhere, when it cannot escape to the lungs, or the

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bicod flow would stop and death follow immediatel}’. Nature has its own emergency measure—though far from a perfect substitute.

Before birth an infant’s lungs are not in use because it cannot breathe and the blood receives its oxygen recharging from the blood of the mother. During the prenatal period a large opening exists between the right and left chambers of the heart and the blue blood received in one nasses directly to the other and star's its return journey through the body at once. In a normal baby this opening closes with the first breath the infant takes and the blood is rerouted through the lungs. Nature compensates the blue baby by leaving a gap in this opening so that the blue blood may escape from the heart and return to the body —but it is still blue blood, starved of oxygen except for the revitalized trickle that does manage to pass through the lungs.

'File blue-baby operation is still so unique—and will always be so intricate —that the operating theatre is invariably crowded when it is performed. You can imagine the hush of interest and attention in the brightly lit room as visiting surgeons and medical students stare down at the white figures grouped about the small form on the operating table below.

The surgeon makes a sharp incision in the child’s chest and collapses the left lung beneath the heart to provide sufficient room in which to work. Then he singles out and identifies, with minute care, all the blood vessels. For the operation is not performed on the heart itself; no attempt is made to restore the flow of blood from the heart into the pulmonary artery. Instead, the surgeon’s delicate task is to establish a “short circuit” between the two main arteries carrying blood from the heart to provide a new route to the lungs.

Rising from the child’s heart he sees the large pulmonary artery which divides in two, one channel leading to each lung; and the aorta, an even larger artery, from which a maze of smaller arteries branch out to carry the blood to various portions of the body.

Now, quickly, the surgeon cuts one of the big brandies of the aorta and neatly bends if to fit into an inch-long slit he has made in the pulmonary artery. The branch is sewn into place with delicate, sure stitches.

Still working swiftly, the surgeon now removes the clamps from the blood vessels. And then, under the eyes of the observers in the amphitheatre, the miracle happens. The bluish, pitiful-looking baby begins to turn pink.

The operation cannot restore the circulation system entirely to normal; the blue blood still flows into the right chamber of the heart, passes directly through the opening into the left, chamber along nature’s “emergency route.” Nor even with the by-pass created by the surgeon does all the blood pass through the lungs on each circuit through the heart. But sufficient circulation through the lungs is established so that enough life-giving oxygen will be carried throughout the child’s system.

Physicians say that a blue baby is afflicted with the “tetralogy of Fallot,” after the man who in 1888 first described the “tetralogy” or quartet of conditions present. These are the diminished size of the pulmonary artery; a defect in the wall between the two ventricles of the heart; the “right-sided” position of the aorta or greater artery; and a marked enlargement of the right side of the heart.

Some babies are blue at birth because the opening between the two heart chambers may take several days to close—the baby is always laid on its right side immediately after birth to assist this closing—but quickly gain a normal coloring as soon as the closure is complete. But the diagnosis “tetralogy of Fallot” was always a death sentence until two years ago. The oldest patient in Fallot’s report was 66 when he died. The late Maude Abbot of Montreal, collector of what is probably the world’s finest museum of heart specimens, had no records of any such sufferer living beyond 36. For the most part these patients had died in their teens at the latest.

Disease Grows

As blue babies grow older, their symptoms are likely to become more severe. Inability to take nourishment results in poor development and impaired nutrition. Some of the more severe cases render the child so breathless during nursing or swallowing that consciousness is lost and life is endangered. When lying quietly, they may have normal color, but the slightest exertion is too much for them.

One case reported by Doctors Blalock and Taussig at Johns Hopkins was that of a nine-year-old girl named Bernice. She had been “blue” at birth and when seen at the Harriet Lane house in Baltimore she was intensely so. She was extremely breathless and would be compelled frequently to squat down on her haunches to get her breath so she could walk a few steps more. The color of her membranes, which should have been pink, was described as “deep mulberry.” Her fingers and toes showed the malformation known as clubbing, a thickening and spreading of the ends of fingers and toes which accompanies chest diseases in which the oxygen supply has long been inadequate.

This girl, after climbing half a flight of stairs and walking 60 feet to her room, leaning forward and almost running, fell upon her bed and panted heavily for half an hour before she could get her breath. After operation, she improved so that she could walk without panting even when she held herself upright.

But before the Johns Hopkins’ doctors dared attempt their first bluebaby operation they had to devote much study to the conditions and conduct experimental operations on animals. In order to learn what happens when the pulmonary artery is too small, it was necessary to produce comparable conditions in animals, and dogs were chosen for this purpose because of their size and the fact that they react physiologically much like human beings. It was on dogs also that the operation was first devised and practiced.

While Blalock and Taussig were laboring in Baltimore, work was going on also in other places. Dr. Robert Gross and associates at Harvard were experimenting with blood-vessel surgery. Dr. Claude Beck at Western Reserve and Dr. Murray in Toronto were also working on heart and bloodvessel operations. In Chicago, at. Children’s Memorial Hospital, Dr. W. J. Potts and Dr. Stanley Gibson and associates, were perfecting a similar operation, based on the same fundamental principles but differing in an essential detail.

Blalock established a new circulation to the lungs in the manner already described. Because this method means cutting off one of the main branches of the aorta, which is then implanted in the pulmonary artery, the cut-off artery’s function must be replaced by

blood flow through another of the main arterial brandies. In the Potts operation, the arterial junction is made between the pulmonary artery and the aorta itself, side by side through artificial openings in to both arteries.

Working on arteries is tricky business. Special clamps were devised by Potts so that he could pinch off a portion of the aorta as you might pinch up a fold of skin off the hack of your hand between the thumb and forefinger. Excluding the blood from this pinched-off area rendered possible the slitting and stitching. Working with delicate silk sutures on the tiny i blood vessels of babies and making : leak-proof junctions between pulsating

I arteries in the narrow confines of the space within the chest, while avoiding injury to lungs and other adjacent, tissues, is a breath-taking project.

Consider that if you place a tourniquet upon an arm to stop bleeding in an I emergency, you are cautioned to release it every quarter hour to avoid death of the tissues of an entire arm or leg. Arteries carry blood under pressure, as shown by the way they spurt when cut. In order to operate upon them, the flow of blood must he stopped for as long a period as the surgeon dares, so that he can operate and yet no harm come to the tissues for which that artery carries the blood of life. The margin of safety is small. In little babies the vessels are tiny and the ¡ patient is a poor surgical risk to start with. Yes, this is daring stuff the stuff of courage and imagination. Yet the tiny patients stand the operations well. They may even improve under the anaesthetic, since this is administered mixed with oxygen.

Almost Halted by Law

The development of the blue-baby operation created a great public uproar in Baltimore when an attempt was made to render the use of dogs illegal for experimental purposes by introduction of a city ordinance. The campaign was launched by people calling themselves antivivisect ionists, which literally means “opposed to cutting live creat ures.”

Antivivisectionists are a small hut noisy organized minority, led by shrewd promotors who play on the natural love of animals and sympathy for suffering which animates the heart: of every decent human being. By spreading outright lies and clever half truths, and quoting scientists who have been dead for a century or more, they try to make it appear that seveiu tort ure is suffered by animals in laboratories, and that no scientific advances have ever corne out of such research. They are well financed and have the support of one of the largest chains of newspapers in the United Shi tes.

The ordinance which they sponsored in Baltimore would have stopped work in the city’s famous medical laboratories at once if it had become effect ive. How it; was beaten makes a dramatic story. The city council chamber was packed for the committee hearing, with wartime medical students, mostly in uniform, vying for space with the adherents of the antivivisectionist cult.

Up to the witness stand walked sixyear-old Marvin Mason, introduced by a professor from the surgical faculty. Louis Mason, Marvin’s father, testified that until recently the parents had no hope for their child—his lips were blue, he was unable to stand without, help, had difficulty in breathing and waked out of sleep with frightening fits of coughing. Declared Mr. Mason: '"Because we believed Marvin had practically no chance to live, we consented

to the operation . . . they've given me a new boy.”

More effective than the sober t.esti monv of the scientists, a council member said after the hearing, was the living evidence of children and their parents, refuting the claims of the cultists that research using animals has never brought about any medical advances. Numbers of scientists, doctors, nurses and medical students had t.o stop constructive work todelend themselves against the unwarranted charges of an irresponsible cult.

Not For All

Enthusiasm for the new surgery must not be allowed to obscure the fact that it is not suitable in some cases. For these the future is as dim as ever. Recently a child was brought to Chicago on funds subscribed hv citizens of his home community, only to he turned away after careful study as unsuitable.

Selection of cases for operation requires careful preliminary study. The heart is capable of withstanding a great deal of extra burden, if its muscle is inherently sound, it its rhythm is unimpaired, and if any defective blood vessels can he surgically corrected. In order to ascertain these factors, the child is given a careful physical examination, which determines the size, function and position of the heart. Heart sounds and murmurs indicate the probable character and extent of the abnormality of blood flow. X-rays indicate the size and shape of the heart and the shadows of the great vessels. The electrocardiograph gives information as to the rhythmic contractions of the heart and the sequence of action of the various chambers. Lungs must be free o( congestion.

We know very little yet as to whal causes a blue baby—why the blood vessels grow normally in the vast majority of human beings and deviate in only a few.

Dr. Gordon Murray thinks a possible cause is an infectious disease suffered by the mother during the first three months of pregnancy. German measles has been observed as the commonest possible offender, hut other conditions affecting the health of the mother during this stage of the baby’s development when the cardiac chambers are being formed may play an important part.

Heredity may he a factor, because sometimes these children have brothers and sisters with similar defects and there may be a history of heart disease in preceding generations.

Observations of the human embryo in various stages of development show how complicated is the process of growth. Beginning with a single straight tube, of which one portion begins to pulsate or heat very early in embryonic life, there evolves the complicated structure of the heart with its four chambers, and four principal sets of valves, the great arteries and veins and the connecting capillaries. So complex is this process that we may well marvel, not that some are defective, hut that so many are functionally a d e quitte despite variations in structure. ★

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