chapter three

Breath and Blood

Anatomical textbooks give the misleading impression that everything in the chest is immediately distinguishable. The unsuspecting student plunges into the laboratory carcase expecting to find these neat arrangements repeated in nature, and the blurred confusion which he actually meets often produces a sense of despair.

JONATHAN MILLER,THE BODY IN QUESTION

The opened thorax, or chest cavity, reveals two large, gray-brown lungs. Though they are similar in size, they are asymmetrical by design—the right lung has three sections, or lobes, where the left lung has only two. The top of the heart is positioned at the body’s vertical midline, directly between the lungs, beneath the sternum. The base, though, veers off to the left, appropriating some of the space into which the left lung could have otherwise expanded. The hearts of the cadavers in the room vary greatly in size. Ours is on the smallest end of the spectrum and is only a little larger than my fist. The heart of the cadaver at the table behind ours is, like the dead man himself, much, much bigger. With the fat that encases it, his heart is nearly the size of a Nerf football.

In order to examine the lungs and heart, we must remove them from the thorax. As with sawing the rib cage, some force is required to do so. We reach beneath the lungs to find the root structures—the forked bronchi, which divide the trachea’s path to serve both the right and left lungs, and the pulmonary arteries and veins, which connect both lungs to the heart. The Dissector, in its typically obtuse tone, instructs us to “push the lung laterally to stretch the root of the lung and carefully transect the root structures.” A great deal of effort must be exerted to stretch the root of the lung, and Tripler and Raj wince as they slide their gloved hands into the pooled embalming fluid at the base of the thoracic cavity. They flex their arms and pull up on the lungs from the connections at their base. I have the scalpel, and I lean over the table at different angles to try to see where to cut. With the lungs still encased by the lateral rib cage, and my partners’ four forearms already filling the space, I must make a nearly blind cut. The trick is to sever the bronchi and the pulmonary vessels while preserving as much of them, and of the lung tissue, as I can. And I must exert care not to slice into the hands of my lab partners. Tamara buries her gaze in the Dissector and reads aloud the path each cut is supposed to take. When the cut is done, the lines of separation are jagged and imprecise, and too little of the pulmonary vessels remain in the thoracic space. Raj and Tripler have soaked the cuffs of their lab coats in the formalin embalming fluid that the lungs had absorbed. We are frustrated and decide to remove the heart after a break for lunch.

 

When we return to the lab in the afternoon, we have a bit of renewed energy for the remainder of the thorax dissection. Now that we have removed the lungs, the heart has more space around it, and once we have cut through the vessels to prompt its release, it comes out easily. But when it’s time to dissect the heart itself, the process feels inexact and takes a great deal of time. The embalming fluid has combined with hardened blood to fill our cadaver’s heart with something that looks strangely like overcooked, processed chicken. All afternoon we are fishing this stuff out of veins, arteries, and heart spaces.

The heart muscle itself does not look so different from chicken—a little stiffer and grayer, perhaps—so, as we attempt to clear out the blood and embalming fluid, we cannot tell the difference between the flesh and the blood. We feel all the while as though we are actually tearing into this woman’s heart. Occasionally we come across wide, thick tubes of hardened blood, and red-black crumbles of it cover everything. We try to run water through the vessels, and the pieces of blood clog the drain of the lab sink. The white cloth covering the body is now dirty and stained, as is the body bag, and the feeling of imprecision and carelessness is exasperating.

For reasons partially physiological and partially philosophical, only the brain supersedes the heart and lungs as the most essential human organ. The loss of brain function invariably leads to cardiopulmonary death, though several hours or days may pass in between. We know that brain death is synonymous with the loss of personhood, and therefore with the loss of life. Surely there will be a voice or two raised here objecting that as long as we can hook bodies up to machines that breathe air into them, and pump blood through them, and maintain the look and feel of a body, warm and alive, then life continues. I disagree. Scientifically I side with the neurologists who designate death as the irreversible cessation of all functions of the entire brain. Philosophically I wade into murky and controversial waters with personal beliefs that the boundaries of death are nebulous. To me the definition of “dead” may extend far enough toward life to include a person whose brain is a physically functional void: the end-stage Alzheimer’s patient, for example, who never wakes but breathes and sends urine from injected liquid food into her diapers.

You could make the argument that a few other organs are indispensable. If the kidneys fail, we need dialysis to rid the body of its waste and toxins or else we poison ourselves, no matter how healthy the heart, lungs, and brain. The necessity of other failing organs has been bypassed by medical advances: If the stomach doesn’t work, we can surgically implant a feeding tube that empties liquid nutrition directly into the intestine; if a cancerous rectum is removed, we can attach an ostomy bag to the patient’s colon to collect the products of the bowels. The gallbladder is routinely removed in people prone to gallstones, with no severe repercussions.

The seventeenth-century English physiologist Richard Lower conducted a simple experiment that illustrated the essential role of the heart and lungs in living beings. Since ancient times it had been known that the blood entering the heart had a purplish-blue color to it, and that the blood exiting the heart was a deep, rich red. Lower demonstrated that this color change took place in the lungs. The question remained: Did the color transformation occur simply due to the blood’s passage through the lungs, or was exposure to air integral to the change? In order to answer this question, Lower performed two experiments. In the first he pumped blood through a dog’s lungs, which he hooked up to a kind of artificial respiration. As long as the “breaths” of the respirator continued, the blood that emerged from the lungs was red. However, if the respirator was stopped, the blood stayed blue.

The second experiment ensured that there was not some intrinsic aspect of the lungs that caused the blood to undergo its change. Into a vial Lower poured purplish blood, which promptly clotted. The top surface of the clot, which was exposed to air, changed to a vivid red, and the blood below the surface remained purple. When Lower removed the clot and turned it over, the colors inverted. The red faded from the portion of the clot that was now at the base of the vial, and the newly exposed surface of the clot brightened from a purple-blue to bright red.

With these two simple experiments, Lower established the collaboration of the heart and lungs in loading blood with oxygen and distributing it throughout the body. And it is this understanding of the precise purpose of the heart that guides our dissection and our study.

The language of the heart is lovely. Divided into distinct functional and structural quadrants, the heart is routinely described as “four-chambered.” Tiny valves open and close—doorways into each chambered space—to allow or prevent the entrance of blood. The top chambers of the heart are the right and left atria. The bottom chambers of the heart are the right and left ventricles.

The right and left sides of the heart work in parallel to one another. The right side collects Lower’s blue blood, drained of oxygen by the workings of the body, and pumps it back to the lungs for fresh contact with inhaled air. The left side is devoted to gathering the blood from the lungs once it is again heavily laden with oxygen and propelling it to the body’s farthest recesses. On both sides the blood first pours into the delicate atria and then flows into the thick-walled, muscular ventricles, which contract mightily to send it to load or unload precious oxygen.

The atria fill simultaneously, then empty into the ventricles during a period of heart relaxation called diastole. The ventricles contract together in systole, sending deoxygenated blood to the lungs and oxygenated blood throughout the body. This emptying and filling, receiving and sending, happens more than once each second. The blood loops and returns, loads and unloads, empties and fills. Systole and diastole are marked by the two sounds of the heartbeat, and they each occur around seventy times a minute. When the body needs more oxygen—in exercise or in fear—the heart may sound 120 times in those sixty seconds. Maybe more. The beating of the heart is one of the first internal things about our bodies that we understand. And yet how can our hearts beat 3,153,600,000 times, give or take a few hundred thousand, over the course of a lifetime? How can they not predictably and catastrophically hiccup sometime in the first year of life with more than 42,048,000 beats in which to do so?

This is one of the experiences in the anatomy lab that I do not expect: When I look at the tissues and organs responsible for keeping me alive, I am not reassured. The wall of the atrium is the thickness of an old T-shirt, and yet a tear in it means instant death. The aorta is something I have never thought about before, but if mine were punctured, I would exsanguinate, a deceptively beautiful word meaning that my blood would spill throughout my body. This is a condition the textbooks describe in a blasé tone, as if they were talking about a fouled relationship: It is incompatible with life.

During this first long day of lab work, I have realized that Raj and I are polar opposites in our approach to dissection. I do not react at all the way I would have expected. Unlike in almost every other realm of my life, in lab I am tentative and cautious, perpetually afraid of cutting something important. But I also feel as though I should cut these things well. Though we each inevitably sail through an important artery with our scalpel, or remove a superficial nerve without even knowing it, I am aware of the fact that in dissection there is no going backward. Raj, on the other hand, moves quickly and with less concern. When we read in the Dissector that we are to cut into the right ventricle so that we can see the thickness of its wall, Raj makes the incision swiftly and with certitude and sort of shreds it. I am a little saddened by that, even though I’m not sure it was avoidable. Before long it becomes clear that neither of our methods is quite right. Raj charges ahead, sometimes inadvertently destroying a structure that we needed to preserve. Though our two styles will grow more similar as the semester progresses, I instinctively cringe while watching him cut, and he sits and sighs to watch me poke and check the book before I proceed. I am so careful that by the end of the day I am way behind schedule. We form a dynamic that will, unbeknownst to us, endure over the course of the semester.

Despite our stylistic differences, Raj and I have nonetheless aligned ourselves as the two lab members who are most comfortable performing the dissections. Tripler and Tamara direct us much of the time from the Dissector, point out landmarks, and ask questions that help all of us study. In most groups the roles sort themselves out in similar—and similarly unspoken—ways. Raj naturally gravitates toward cutting, as he has since the first moments of lab. Yet I am surprised to learn that even if the actions we are asked to do are distressing, I am more comfortable doing the dissections than observing them. When Trip takes over for me, I hover, restless and bored.

It is only the first afternoon of lab, and already, when Trip asks me questions, I am feeling behind. There are so many names of veins and arteries, so many tiny parts to the heart and body that we aren’t even sure we have correctly found. Many more don’t seem worth the effort to locate. We can easily see the superior and inferior venae cavae. But seemingly endless numbers of other landmarks are more like the oblique pericardial sinus, a space within the heart bounded by five vessels into which we stick our fingers and kind of shrug: I guess that’s it. Whether or not it is, we move on.

When the first day of dissection comes to a close, Tripler and I head to our lockers. We chat absentmindedly as if today is no different from any other day for us, as if we haven’t touched our first dead body—cut it, even, taken out its heart and held it in our hands. Its heart. The “it” is what bothers me.

“Trip,” I say, “I just feel weird about…”

“The face,” she says. “Me, too.”

We walk back to the lab door, fumble in our notes until we find the combination. We are the only ones in the room, and it is strange all over again. When we stand above our cadaver as we have done for the last six hours, the room is silent. Twenty bodies in the room, only we two breathing.

“It doesn’t feel right to cut her up without knowing what she looked like before,” I say. The reiteration is to buy time. We won’t see what she looked like before, of course. She is shorn; she is the gray-green of formalin embalming. We can tell even through the cheesecloth, through the plastic bag, that her mouth is open. Still, she will look less herself by the time we are meant to take off the bag for the face dissection at the term’s end.

Trip nods. She is resolute. She unwraps a new blade for the scalpel and slides it onto the handle. She cuts the string that ties the bag over the head at the neck. I pull off the bag, unwrap the cloth.

We hold our breath.

The truth is, she is beautiful.

Fine features; small, angular nose; thin lips. A face capable of intensity. At her throat a dark braid of stitches closing the spot where her blood was exchanged for embalming fluid.

Her eyes are open. Her mouth is open. Tongue. Teeth. She looks as if she would speak if she were not this wrong hue.

I did not expect her to be beautiful.

I bring my partner, Deborah, to the lab that night. “It is so clear that these are not people any longer,” she says. She is right. And she is wrong. The time eddies and swirls. They were people, are people, were loved, are loved, were bodies, are bodies, have died. And what else?

 

The syllabus informs us that we will spend two entire weeks dissecting the thorax, due to the sheer number of structures to consider. During the second week of these dissections, our anatomy instructors have gone to a butcher shop to get a heart, trachea, and lungs from a cow that was butchered this morning. The cow’s trachea is wide, bright white, and plasticky, and it looks like the hose of a bilge pump. The heart is huge and a great relief, as it can easily illustrate the tiny structures that are so difficult to locate in our human specimens. We see the oversize tricuspid valve and the chordae tendineae, the fibrous cords that connect the cusps of the valve to the papillary muscles. When the heart contracts, the papillary muscles also contract to pull on the cords and prevent the cusps from inverting into the atrium. In our human hearts, the chordae tendineae are a thickness somewhere between thread and embroidery floss, but in the cow heart they are far less fragile. The cow’s lungs are the most remarkable. At first they look like a small, pink, split manta ray. We touch them and they squish, like a sponge filled with water. Then Dale hooks them up to an air hose and they grow stiff instead of spongy and inflate until they are half of a huge beach ball. They swell to five or six times their original size, and their capacity for expansion is permanently fixed in our minds. Trip, Tamara, Raj, and I return to our cramped and difficult heart, to our cadaver’s gray-brown lungs, spotted with blue specks of pollution, amazed at them.

Our replenished energy does not make up for our growing sense of falling behind, and when we finish the second week of dissection, we know we will have to spend additional time in the lab before we become responsible for still more material in the week that follows. To that end I return to the lab on Saturday morning to study with Lex, a friend from class. Lex is a sweet soul with a British accent and a persistently half-untucked shirt who alternates between thinking he should be a doctor and thinking he should fix up old cars. He is an insomniac who studied literature at Bennington, and so from time to time he’ll stay up all night with books of poetry and will come in waving pages of Mary Oliver poems for me to read.

During our Saturday-morning study session, I am teasing Lex about being both a vegetarian and a chocoholic when we stumble upon one of the most wondrous moments I experience in lab. We are looking at the semilunar valves in the pulmonary trunk and aorta, and they look just like their names, like little half-moons that work passively and without musculature, unlike the tricuspid valve with its papillary muscles. The idea behind them is that they surround the lumen of the vessel into which the blood is being pumped from the ventricles—on the right the pulmonary trunk and on the left the aorta. If the blood flows forward, they are pressed closed against the side of the vessel, so as not to impede the flow. However, should any blood attempt to flow backward, it would catch on the flaps of the three semilunar valves and instantly fill and open them, thereby closing off the vessel. When full, each of the cusps presses up against the sides of the others, their joinings splitting the circle of the vessel’s lumen into perfect thirds. To visualize the valves’ function, Lex and I decide to take a heart to the sink and pour water through the pulmonary trunk toward the ventricle. The semilunar valves work like a dream, catching the water as sails catch wind, closing fast and preventing any leakage. It is astonishing, almost impossible to believe.