Saturday, January 02, 2010

There is power in the blood

From In His Image by Dr. Paul Brand:
A fly is a nobler creature than the sun, because a fly hath life, and the sun hath not. - St. Augustine
My entire career in medicine traces back to one dreary night at Connaught Hospital in East London. Before that night I had stubbornly resisted all pressures to enter medical school. For some time my family had tried to influence me toward medicine, even to the extent of an uncle offering to pay all school expenses. And just before I left high school my mother's return from India gave us an opportunity for a serious talk about my future.

We sat together before a hissing gas fire in her bedroom. After a separation of six years, I was struck by her changed appearance. Twenty years in rural India had worn away the soft facade of British gentility and etched an unmistakable resolve in the lines of her face. Grief covered her face like a mask - my father had died of blackwater fever that same year. She had come home a desperately broken person, seeking a place of refuge.

It seemed strange for me to be abruptly planning my future with someone I had not seen in six years. "You know how much your father loved the medical work in the mountains," she began gently. "He always wished he had become a doctor with a proper degree instead of having to rely on a short training course at Livingston College. If he had . . . who knows, he might still be with us. He would have known how to treat the fever."

Her eyes filled up and she paused a few minutes, swallowing repeatedly. She went on to tell me of new laws in India that would prohibit all but qualified doctors from practicing medicine. Then she looked directly into my eyes and said gravely, "Paul, your father always dreamed that you could take up where he left off and return as a real doctor -"

"No, Mother!" I stopped her in mid-sentence. "I don't want to be a doctor. I don't like medical work. I'd rather be a builder. I could build houses and schools and even hospitals. Anyhow, I don't want to be a doctor."

Although she did not argue, I could sense a barrier had arisen between us. I mumbled some excuse and left, with a gnawing awareness that I was disappointing her as well as my father and my generous uncle by not studying medicine. I could not tell my mother, and probably did not even admit to myself at the time, the real reason: a visceral reaction against blood and pus. Memories had sickened me ever since childhood. . . .

* * *

Five years after my awkward conversation with Mother, I found myself unavoidably working at Connaught, a small hospital on London's East Side. I had kept my promise of learning the building trade, having apprenticed as a carpenter, a mason, a painter, and a bricklayer. I loved it. Evening classes in civil engineering had also exposed me to the theories behind construction. I chafed to return to India to practice my trade. The mission advised enrolling in the same Livingston College course in hygiene and tropical medicine that my father had taken. I was assigned to a local hospital to do dressings in the wards and to learn basic principles of diagnosis and treatment.

It was during one evening of my stint at Connaught that my whole view of medicine - and of blood - permanently shifted. That night hospital orderlies wheeled a beautiful young accident victim into my ward. Loss of blood had given her skin an unearthly paleness, and her brownish hair seemed jet-black in contrast. Oxygen starvation had shut down her brain into a state of unconsciousness.

The hospital staff lurched into their controlled-panic response to a trauma patient. A nurse dashed down a corridor for a bottle of blood while a doctor fumbled with the transfusion apparatus. Another doctor, glancing at my white coat, thrust a blood pressure cuff at me. Fortunately, I had already learned to read pulses and blood pressure. I could not detect the faintest flicker of a pulse on the woman's cold, damp wrist.

In the glare of hospital lights she looked like a waxwork Madonna or an alabaster saint from a cathedral. Even her lips were pallid, and as the doctor searched her chest with his stethoscope I noticed whitened nipples on her small breasts. Only a few freckles stood out against the pallor. She did not seem to be breathing. I felt sure she was dead.

The nurse arrived with a bottle of blood and buckled it into a metal stand as the doctor punctured the woman's vein with a large needle. They fastened the bottle high and used an extra-long tube so that the increase in pressure would push the blood into her body faster. The staff told me to keep watch over the emptying bottle while they scurried off for more blood.

Nothing in my memory can compare to the excitement of what happened next. Certainly the details of that scene come to me even now with a start. As the others all left, I nervously held the woman's wrist. Suddenly I could feel the faintest press of a pulse. Or was it my own finger's pulse? I searched again - it was there, a tremor barely perceptible, but regular. The next bottle of blood arrived and was quickly connected. A spot of pink appeared like a drop of watercolor on her cheek. It began to spread into a beautiful flush. Her lips darkened pink, then red, and her body quivered with a kind of sighing breath.

Then her eyelids fluttered lightly and parted. She squinted at first, and her pupils constricted, reacting to the bright lights of the room. At last she looked directly at me. To my enormous surprise, she spoke, asking for water.

That young woman entered my life for only an hour or so, but the experience left me utterly changed. I had seen a miracle: a corpse resurrected, the creation of Eve when breath entered into and animated her body. If medicine, if blood could do this. . . .

I picked up the empty glass bottle, streaks of blood still smearing its side, and read the label. Who had given these pints of life? I wanted some mental picture of the donor who had made the miracle possible. In our registry I discovered the donor lived in Seven Kings, Essex, a town where I had worked for a building construction firm. With eyes closed I envisioned one of the burly workmen from that blue-collar neighborhood. At that moment he could have been out climbing ladders or laying bricks, exuding strength and vigor, oblivious to the frail young woman revived by his own blood cells miles away.

By the time I finished my year at Livingston College I was incurably in love with medicine. A short time later, feeling some shame at my vacillation, but compelled by an inner sense, I turned back and accepted my uncle's offer of support for medical school. The memory of shed blood had kept me out of medicine; the power of shared blood ultimately brought me to it.

* * *

For most of us, the organ of blood, if one can think of this fluid mass as an organ, comes to consciousness mainly when we begin to lose it. Then, the sight of it in tinted urine, a nosebleed, or a weeping wound provokes alarm. We miss the dramatic sense of blood's power that I saw demonstrated in the Connaught patient - the power that sustains our lives at every moment.

"What does my blood do all day?" a five-year-old child asked, peering dubiously at his scraped knee. Whereas the ancients would have responded with elegant references to ethers and humours borne in that "pure clear lovely and amiable juice," perhaps a technological metaphor would serve best today. Imagine an enormous tube snaking southward from Canada through the Amazon delta, plunging into oceans only to surface at every inhabited island, shooting out eastward through every jungle, plain, and desert in Africa, forking near Egypt to join all of Europe and Russia as well as the entire Middle East and Asia - a pipeline so global and pervasive that it links every person worldwide. Inside that tube an endless plenitude of treasures floats along on rafts: mangoes, coconuts, asparagus, and produce from every continent; watches, calculators, and cameras; gems and minerals; forty-nine brands of cereals; all styles and sizes of clothing; the contents of entire shopping centers. Six billion people have access: at a moment of need or want, they simply reach into the tube and seize whatever product suits them. Somewhere far down the pipeline a replacement is manufactured and inserted.

Such a pipeline exists inside each one of us, servicing not six billion but one hundred trillion cells in the human body. An endless supply of oxygen, amino acids, nitrogen, sodium, potassium, calcium, magnesium, sugars, lipids, cholesterols, and hormones surges past our cells, carried on blood cell rafts or suspended in the fluid. Each cell has special withdrawal privileges to gather the resources needed to fuel a tiny engine for its complex chemical reactions.

In addition, that same pipeline ferries away refuse, exhaust gases, and worn-out chemicals. In the interest of economical transport, the body dissolves its vital substances into a liquid (much as coal is shipped more efficiently through a slurry pipeline than by truck or train). Five or six quarts of this all-purpose fluid suffice for the body's hundred trillion cells.

When blood spills, it appears as a uniform, syrupy substance ranging in color from bright red to dark purple. . . .

A simple experiment confirms the composite nature of blood. Pour a quantity of red blood into any clear glass and simply wait. Horizontal bands of color will appear as various cells settle by weight, until the final multilayered result resembles an exotic cocktail. The deepest reds, comprising clumps of red cells, sink to the bottom; plasma, a thin yellow fluid, fills the top part of the flask; platelets and white cells congregate in a pale gray band in between.

What the telescope does to nearby galaxies, the microscope does to a drop of blood: it unveils the staggering reality. A speck of blood the size of this letter "o" contains 5,000,000 red cells, 300,000 platelets and 7,000 white cells. The fluid is actually an ocean stocked with living matter. Red cells alone, if removed from a single person and laid side by side, would carpet an area of 3,500 square yards. . . .

When a blood vessel is cut, the fluid that sustains life begins to leak away. In response, tiny platelets melt, like snowflakes, spinning out a gossamer web of fibrinogen. Red blood cells collect in this web, like autos crashing into each other when the road is blocked. Soon the tenuous wall of red blood cells thickens enough to stanch the flow of blood.

Platelets have a very small margin of error. Any clot that extends beyond the vessel wall and threatens to obstruct the vessel itself will stop the flow of blood through the vessel and perhaps lead to a stroke or coronary thrombosis and possibly death. On the other hand, people whose blood has no ability to clot live short lives: even a tooth extraction may prove fatal. The body cannily gauges when a clot is large enough to stop the loss of blood but not so large as to impede the flow within the vessel itself. 1

* * *

A view through a microscope clarifies the various components of blood but gives no picture of the daily frenzy encountered by each cell. Red cells, for example, never sit motionless. From their first entrance into the bloodstream they are pushed and shoved through rush hour traffic. Beginning the cycle at the heart, they take a short jaunt to the lungs to pick up a heavy load of oxygen. Immediately they return to the heart, which propels them violently over the Niagara Falls of the aortic arch. From there, highways crowded with billions of red cells branch out to the brain, the limbs, and vital internal organs.

Sixty thousand miles of blood vessels link every living cell; even the blood vessels themselves are fed by blood vessels. Highways narrow down to one-lane roads, then bike paths, then footpaths, until finally the red cell must bow sideways and edge through a capillary one-tenth in diameter of a human hair. In such narrow confines the cells are stripped of food and oxygen and loaded down with carbon dioxide and urea. If shrunken down to their size, we would see red cells as bloated bags of jelly and iron drifting along in a river until they reach the smallest capillary, where gases fizz and wheeze in and out of surface membranes. From there red cells rush to the kidneys for a thorough scrubbing, then back to the lungs for a refill. And the journey begins anew.

A person can live a day or two without water and several weeks without food, but only a few minutes without oxygen, the main fuel for our hundred trillion cells. Heavy exercise may increase the demand for oxygen from the normal four gallons up to seventy-five gallons an hour, prompting the heart to double or even triple its rate to speed red cells to the heaving lungs. If the lungs alone cannot overcome the oxygen shortage, the red cells call up reinforcements. Instead of five million red cells in a speck of blood, seven or eight million will gradually appear. After a person spends a few months in the rarefied atmosphere of Colorado's mountains, for example, up to ten million red cells will fill each drop of blood, compensating for the thinner air.

The pell-mell journey, even to the extremity of the big toe, lasts a mere twenty seconds. An average red cell endures the cycle of loading, unloading, and jostling through the body for a half million round trips over four months. In one final journey, to the spleen, the battered cell is stripped bare by scavenger cells and recycled into new cells. Three hundred billion such red cells die and are replaced every day, leaving behind various parts to reincarnate in a hair follicle or a taste bud. 2

The components of this circulatory system cooperate to accomplish a simple goal: nourishing and cleansing each living cell. If any part of the network breaks down - the heart takes an unscheduled rest, a clot overgrows and blocks an artery, a defect diminishes the red cells' oxygen capacity - life ebbs away. The brain, master of the body, can survive intact only five minutes without replenishment.

Blood once repulsed me. I saw it as the most distasteful part of medical treatment. Now . . . I feel like assembling all my blood cells and singing them a hymn of praise. The drama of resurrection enacted before me in Connaught Hospital takes place without fanfare in each heartbeat of a healthy human being. Every cell in every body lives at the mercy of blood.

1 India has a very feared species of snake, the "eleven-step adder," so named because its toxic bite is said to allow the victim time for just eleven more steps. Like all vipers, it kills with a clotting toxin. If its fang penetrates a major vein, say, in the leg, all the blood in the channel between the heart and leg clots at once. If the toxin merely reaches a minor vessel, an amazing thing happens. The poison draws platelets to the tissue like a magnet. Elsewhere in the body platelets simply vanish so that the blood cannot clot anywhere. Then, the smallest scratch will kill the victim or he may bleed internally in the brain or intestine. Bleeding cannot be stopped. Thus a viper's toxin can kill in two opposite ways: a devastating clot or an equally devastating inability to clot. The Haffkeine Institute in Bombay (Mumbai) milks these adders and uses minute amounts of the dried toxin to treat excess bleeding in patients.

2 The body provides the energy for the red cells' travels by employing the heart, an organ that deserves a book exclusively devoted to it. Primitive artificial hearts are now available, but I would like to see a government design specification sheet for a truly adequate replacement.

  • Fluid pump with 75-year life expectancy (2,500,000,000 cycles).
  • No maintenance or lubrication required.
  • Output: must vary between .025 horsepower at rest and short bursts of 1 horsepower determined by such factors as stress and exercise.
  • Weight: not to exceed 10.5 ounces (300 grams).
  • Capacity: 2,000 gallons per day.
  • Valves: each to operate 4,000-5,000 times per hour.

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