The Source of All Things
Page 3
* * *
The patient has to be operated on immediately, as now only a paper-thin wall stands between life and death. It won’t withstand the enormous pressure for much longer. Blood is already seeping through the remaining dam, and soon it will break. In the pericardium (the heart sac) there is already a large amount of blood, pressing on the heart. The patient’s heart needs to be relieved if we are to save his life, as he has a condition known as cardiac tamponade. As the wrong channel is being used, the heart is choked by its own blood, which fills the pericardium. Even a strong heart cannot bear this for long. And this one is not very strong. We watch the drama on the ultrasound monitor that provides a live visual of what is happening. Beads of sweat appear on the assistant’s forehead. The nurse looks at me questioningly. The experienced anesthetist informs me that the aortic valve is leaky and may have to be replaced or repaired.
“But that doesn’t matter at the moment,” I reply gruffly, even though she is right. It really does not matter now. My reaction betrays my own nervousness. The patient’s blood pressure is low and he is beginning to go into shock. Life or death. I need to concentrate on the most important issue.
* * *
“Knife,” I say curtly to the nurse and cut the skin above the sternum. A thin stream of blood follows the scalpel’s straight incision. The pressure on the blade is just strong enough to cut the skin but not yet the tissue underneath. There will be a long scar above the heart, from the throat to the end of the sternum; it will mark the patient for the rest of his life. How long that will be I don’t want to predict right now. The only thing that is clear is that the patient—of whom I only see a small section, as he is covered in green cloth—is critically ill. With a further cut I advance to the sternum. Wordlessly, the nurse passes me the pneumatic surgical saw. Its howling sound drowns out the diminishing bleeps of the heart rate monitor. Someone hastily fetches the sternal retractor—a kind of jack that will hold open and prize apart the bony ribcage. Deep down I see the heart sac, inflated close to bursting, full of blood gleaming a dark shade of red that suggests danger.
“Scissors,” I say. When everything is on the line, you make do without “please” and “thank you.” I open the heart sac. If the aortic wall doesn’t hold now, it is highly likely the patient will bleed to death. But if I don’t open the heart sac, he will have a cardiac arrest. We have to act immediately.
* * *
I feel nothing. With the calmness that always comes over me when I operate, I do what needs to be done. My movements slow down for a moment and I look into the eyes of my assistant. He is experienced. I like and trust him. He has often been by my side during difficult operations and has helped me enormously. He knows what is at stake and what will happen now. He already has the big suction drain in his hand. I nod, he nods back. All of this happens in less than a second. Then I cut into the heart sac, and immediately half a liter of blood squirts out. We can no longer see anything. It is like looking into a bath of blood: you can’t make out the bottom beneath all the muddy, bloody liquid. You don’t know how dangerous it is in there or what lurks below. The suction runs on maximum, and finally I see the heart again. This organ, usually so majestic, is crouched in an unnatural, deformed position in the left corner of its home, the heart sac. Normally the heart is proudly enthroned in the middle, but now it has been pushed aside by the enlarged aorta.
“Pressure rising,” I hear the anesthetist say. I take a deep breath; the strange icy-cold feeling in my body subsides. The aorta has held and the lethal threat has been averted. For now.
* * *
I prepare the connection to the heart-lung machine. The whole team knows that we are about to undertake one of the biggest, most complex, and most dangerous operations that can be carried out in heart surgery, or on a person in general. The extent of the operation is not yet clear. That, too, is particular to this illness; even the most advanced imaging processes cannot tell you which parts of the aorta and arteries, potentially leading to the brain, are affected. The only thing that is clear is that it will take many hours—and the outcome is unknown.
As the aorta is damaged, the heart-lung machine will be connected via the subclavian artery below the collarbone. This artery is now exposed; parallel to it a wire is pushed into the heart via a large vein in the groin—under the stern gaze of the anesthetist, who follows the procedure on ultrasound and tells me if my wire is going the right way.
“Thirty thousand units of heparin,” I command. This is to make it impossible for the patient’s blood to clot.
“Thirty thousand units of heparin administered,” I hear shortly afterward. I like these clear and concise calls. It is like in a space station or an airplane. Deep concentration, without frills—the nitty-gritty.
The cannulas are inserted, the heart-lung machine is started. “Full flow, six liters,” reports the cardio technician. That reassures me immensely. So far we have been acrobats on a high wire. Every complication could have been deadly. Now we have installed a parallel circuit, enabling us to return to the patient the blood we suck away and to shut down the heart at any time. But we aren’t quite there yet. First, I fully open the heart sac and assess the damage. The aorta, life’s magnificent and powerful channel, lies bloated and bloodshot in the opened chest. We don’t know much about the patient, but his blood pressure has been too high for years and the connecting tube from heart to body continued to expand unnoticed and without the patient being able to sense any symptoms—until the innermost layer tore. The question is only where exactly the tear is and how much tissue has been damaged. Does the tear reach all the way to the brain arteries or down to the coronary arteries? Sometimes a tear can also come close to a heart valve, namely the aortic valve, so it also has to be replaced and repaired. At exactly the point where it emerges from the heart, the aorta is a little wider. Leonardo da Vinci knew that this widening, called the sinus of Valsalva, swirls the blood in a symmetric and even harmonious fashion. Even today the purpose of this swirling is not fully understood, but it improves the profile and properties of the flow. Possibly there is information encoded in these swirls which the heart sends to the body and the brain.
However, one thing is clear. This pipe needs to be replaced, and that can only happen with a complete shutdown of the cardiovascular system. So if the patient holds on, there will be a point in the next few hours when not only the heart pauses but the heart-lung machine as well. That is the unique feature of this particular operation. My instruction is: “Cool down to eighteen degrees of rectal temperature.” So using the heat exchanger of the heart-lung machine, the blood is cooled down progressively until the body’s core temperature in the bowel is 18°C. Why there? The temperature taken in the bottom is the true temperature, as it is measured within the body, and is more reliable than measuring the skin temperature under the arm. It takes at least an hour to cool down a person by lowering the temperature of their blood from 36°C to 18°C. I use this time to lay open the aorta and its connections to the brain and wrap them in sterile cloth strips in order to mark every single blood vessel and thereby gain an overview of the anatomy. Although in principle most people follow the same blueprint, we are vastly diverse creatures. Just as two identical faces are extremely rare, the way we are arranged internally is also individual. I tread with the utmost care, as if the area around the aorta were a minefield. One careless move and the life-threatening situation, which we have somewhat under control at the moment, will escalate.
* * *
At about 26°C, ventricular fibrillation sets in. This would be the cause of death of someone suffering from hypothermia after falling into a crevasse or drifting in the Arctic Sea. In our case this reaction is intentional. While my gaze is fixed on the aorta and my vision rather restricted by glasses with a magnification of two and a half, I receive my information from the cardio technician, who has his eyes constantly on the monitors: “Heart fibrillating.” I look past the magnifiers and see it too. Even though this situation
has been deliberately brought about, a fibrillating heart is still a picture of misery. Ever since witnessing my first heart operation some decades ago, I am always affected when a heart fibrillates. It looks so miserable, evoking my pity: the last twitches of a dying creature. Of course I know the heart is not a creature, but in some way it seems like one. It reminds me of a bird that has flown into a windowpane and is now twitching to death. The incomparable beauty of a heart’s movement and its natural power are laid low. With this operation, however, the shutting down of the heart is part of the unavoidable process and part of its success. I request a twenty-five-centimeter-long aortic clamp and put it on the aorta with the utmost accurateness and care. I close it millimeter by millimeter until a soft click indicates it is locked in place. Every sausage has two ends. The clamp is sitting in the middle of the sausage. The end toward the heart, including the heart itself, is no longer supplied with blood.
* * *
From now on we fight even harder against time. Even at these low temperatures, the heart’s blood supply should not be cut off for more than ninety minutes, if at all possible, in order for the heart muscle not to become damaged. I open the aorta close to the heart with a scalpel and see inside it for the first time. The surface of the inner wall, formerly baby-skin smooth, is now fissured like a rocky potato field. Life’s most important vein is corrugated by many centimeters of calcium. The tear is clearly visible: the innermost layer, called the endothelium, is hanging down like torn-off wallpaper in a house that needs restoration. Temporary stitches are put in, as it is important to remain visually in control and be able to clearly see every corner. The tear ends a centimeter and a half above the coronary arteries, and the aortic valve has also not been affected. One could say the patient is lucky. But will his heart continue to serve him? We inject a mixture of blood and potassium into the coronary vessels with special cannulas. The heart stops twitching and fibrillating. The desired heart shutdown has been achieved. In this state the heart will need the least amount of energy and oxygen. Neither are available at the moment. The heart will have to hold its breath—and hang on.
* * *
At one end of the sausage we will need to attach a new pipe. I measure the size for a prosthetic tube. The tissue to which it needs to be attached is fragile like wet toilet paper, so I have to sew in felt rings to strengthen it. I am familiar with this kind of tailoring from my mother. She used to sew strengthening material into my torn pants so the patches would hold. Leaky seams will lead to nasty complications. But only many hours into the operation will I know if everything is really tight. I stitch with the utmost diligence and concentration. Even the tiniest tear, a slightly too-big distance from one stitch to the next, can become a rapid leak. The seam is a success and we approach the epicenter of the operation. The patient’s body temperature is at 18°C. His head is resting on ice to protect the brain.
* * *
“Head further down, suction ready, stop machine,” I say, this time really commandingly. The patient no longer has any circulation, the heart-lung machine’s rotation pumps also stand still. His head is lowered so no air will penetrate the head vessels. You could call his state clinical death. Everything will have to work, not a minute or even a second must be wasted. The total cardiovascular arrest should last forty-five minutes at most so the brain is not damaged. This technique is only possible because the brain’s demand for oxygen is very low at 18°C—which is why accident victims sometimes survive in ice-cold water. Because of the intense hypothermia, they are not brain-dead and the heart can resume its work.
I open the aortic clamp and look into the part of the aorta that leads to the brain—the other end of the sausage. You can’t look any deeper into a human being. It is very still in the operating room. Usually during an operation, the patient still has circulation when I look into their resting heart. Not this one. His connection to life has been shut down—hopefully only temporarily. Medical team and patient are on a path through the no-man’s-land between life and death.
Meticulously, we inspect the interior of the aorta and its branches leading to the brain arteries, one of the most important nodes in the human blood vessel system. The heart gives 30 percent of its blood to the brain, even though the brain accounts for only 2 percent of body mass. Without this massive subsidy of energy from the heart, our high-performance processor and server room would break down immediately. Under normal circumstances the brain continuously tells the heart how much blood and oxygen it needs, and the heart’s pumping is essential in maintaining this cerebral circulation.1 Even if the heart is not well, is in shock, or is massively damaged, it will try to maintain blood supply to the brain, at the expense of the skin and other organs. If there is such a thing as unconditional love, this is pretty close.
* * *
The aortic arch looks better than I feared. No further tear is visible. So the connections to the brain will not have to be repaired and implanted separately. I remove as much of the damaged aortic tissue as possible and support the rest with felt strips. I carefully measure a number of times and cut the end of the prosthetic tube accordingly. The tube must not be too short but must not bend either. Felt strips are attached again, and the tube is now sewn on at the other end too, with utmost care. Blood rich in oxygen is injected through special cannulas in order to further protect the brain. Before finishing the seam, the whole system will have to be vented thoroughly to avoid damage to the heart and brain from air pockets.
Simultaneously, the heart-lung machine is started slowly and the aortic clamp released. This is a decisive moment as now it will be revealed whether the seams are tight or there is any bleeding. At this stage in the intervention, the patient’s blood is severely affected. It is reminiscent of tap water—there is not the slightest clotting, it drips and leaks everywhere. One has to trust that once clotting begins things will improve. But that might take a while.
We have now been operating for three hours and will continue to do so for another three at least. We start to warm the patient; he will be at his original body temperature of 36°C in about an hour. At the moment there is nothing to prepare. It is four o’clock at night, or in the morning … and we wait. Everyone is exhausted, their faces gray, their eyes bloodshot. A leaden fatigue clings to the ceiling and wants to descend on us. I tell my assistant to go and have a coffee, and lethargically watch the temperature indicator, which is climbing torturously slowly. The heart has started to fibrillate again and is being defibrillated at 28°C. For this purpose two metal spoons, which look like salad servers, are placed on the heart, and an electric shock is administered. The heart twitches briefly and continues to fibrillate. We try again. Nothing. Third time lucky—the heart is beating again. And even though we are completely exhausted, we are glad. We’re immediately awake again. The patient’s beating heart, even though it appears to be a bit disoriented (at least that is my interpretation), impresses us with its vitality. There is nothing more beautiful than a beating heart. After all these years I am still deeply moved by it, time and time again. It is still a damn miracle. I love being able to see it so closely.
* * *
Low conversations begin, someone tells a joke. We don’t know if the patient will survive the operation and what the damage will be if he does. But his heart is beating, which is a good start. And the beat is a strong one. It appears to rejoice with us.
* * *
The red-haired anesthetist slams her metal stool down in front of the table, climbs up, and observes the result of the operation critically. She calls the green cloth that separates the patient from the area of operation the “blood–brain barrier.” The operating room is amused. Still, we have left behind a bloodbath. Which is what the anesthetist is mercilessly pointing out with grand understatement: “It’s still a bit wet. I have RCC, FFP, and PC at the ready. Tell me when I should use them.” These are blood and clotting agents which have been generously donated by others: red blood cells, plasma, and platelets. The patient will need the
m in copious amounts.
We sew on the pacemaker cables and wean the patient from the heart-lung machine; the heart is working well. Here and there more stitches are needed where the increasing blood pressure reveals leaks. Then we remove the cannulas and stitch up the holes. After more than six hours of operating and administering forty bags of blood products, clotting is still very limited. Such an operation is also a battle of material: it produces several bags of waste.
We did what we could. Now the patient has to recover. We leave him open, which is to say the chest is provisionally stuffed with sterile fabric and closed with self-adhesive film. Sometimes this procedure is repeated over several days—until the patient’s own clotting mechanism has been restored. Until then he will remain in intensive care under anesthetic in a critical condition.
THE BLEEDING HEART
I was around eight years old and I stared at the altar in fascination. I liked to accompany my grandma to the Maria-Hilf chapel near Roggenburg, Bavaria—just a ten-minute walk—to see the heart. It was Mary’s. The heart was very red, very fleshy, and she held it in both hands in front of her breast. It looked as if it held a secret, and I found it revolting. But I was fascinated at the same time, so I stared at it, mesmerized, while my grandma knelt down beside me and prayed. On the way home, she would always tell me the same story from the Thirty Years’ War, which she could recount as if she had been there. Her “we” didn’t just include her family but our whole village. Soldiers had plundered and pillaged our village. A brave priest, the last survivor, remained in the monastery disguised as a peasant. “But on the hill where the chapel stands today,” Grandma’s voice became softer, “they caught him and hanged him from an oak tree.” Now she whispered with reverence: “But Mary came to his aid and stopped the rope from strangling him.”