How Doctors Think (6 page)

Extreme arousal happens not only during the first encounter with a William Morgan, but throughout internship and residency. During this training, young doctors gradually learn how to move themselves back from the edge of the Yerkes-Dodson curve toward points of effective performance. My internship group did so largely, as interns still do, by following the maxim "See one, do one, teach one." In the emergency room or in the intensive care unit or on the wards, you saw "one," which might be a massive heart attack, or a pulmonary embolism, or a brain hemorrhage, or a grand mal seizure. If you were lucky and it was during the day, the senior resident would not be at home sleeping but would be called to the scene and would rapidly assess the situation, issue orders, and work to save the patient. As the intern "seeing one," you pitched in, starting, in part, to "do one" by following the resident's instructions as you listened to the heart and lungs or examined the widened pupils or inserted an airway into a clenching mouth. You listened closely to what the senior resident ordered, the measures he initiated to supply oxygen to an injured lung or stabilize blood pressure with a failing heart or stanch a hemorrhage or arrest the electrical discharges of a seizing brain. If you were very lucky, despite the rush of the moment, the senior resident might offer a few explicit words, explaining the tricks he used to pass a breathing tube into the trachea and not mistakenly into the esophagus, how to adjust the dose of an anticoagulant for a pulmonary embolism, which drug he preferred to try to restore falling blood pressure or stop a seizure. The next time, you were more ready to imitate him. You were beginning to think and act simultaneously.

It took Dr. Burnside some fifteen seconds to figure out what was wrong and what to do for William Morgan. Physicians had fifteen years to ponder Anne Dodge's case. Anne Dodge was dying a slow death from malnutrition; William Morgan would have died quickly from acute heart failure. Anne Dodge's condition called for the withdrawal of a single dietary component, gluten; William Morgan's demanded complex intervention, opening his heart and inserting a new valve. Given these contrasts, you might imagine that a doctor thinks differently with an Anne Dodge than with a William Morgan. Certainly, time and task determine how much deliberate analysis is called for versus how much rapid intuitive thinking is required. But I would argue that important similarities outweigh any differences. In both cases Myron Falchuk and John Burnside recognized a clinical pattern. And in both cases they had to modulate their inner emotions. Falchuk had to avoid the negative feelings that physicians have for patients labeled as "psychiatric," seeing such people as neurotic, cloying, deranged, and generally delusional, a burden because they do not tell the truth, their physical complaints not worth taking seriously because their symptoms originate not in the chest or bowels or bones but in the mind. A wealth of research shows that patients thought to have a psychological disorder get short shrift from internists and surgeons and gynecologists. As a result, their physical maladies are often never diagnosed or the diagnosis is delayed. The doctor's negative feelings cloud his thinking. Burnside faced a different challenge: to lower his level of arousal so he could think and act quickly and effectively. In each case, correctly adjusting the emotional temperature saved a life. Cognition and emotion are inseparable. The two mix in every encounter with every patient, obvi ously in a clinical catastrophe like William Morgan's, more subtly in a drawn-out chronic case like Anne Dodge's.

The importance of a physician's insight into his inner state came into sharp focus when I told colleagues what had happened in William Morgan's room. My fear and anxiety were familiar to them. But what I and my colleagues rarely recognized, and what physicians still rarely discussed as medical students, interns, residents, and indeed throughout their professional lives, is how other emotions influence a doctor's perceptions and judgments, his actions and reactions. I long believed that the errors we made in medicine were largely technical ones—prescribing the wrong dose of a drug, transfusing a unit of blood matched for another person, mislabeling an x-ray of an arm as "right" instead of "left." But as a growing body of research shows, technical errors account for only a small fraction of our incorrect diagnoses and treatments. Most errors are mistakes in thinking. And part of what causes these cognitive errors is our inner feelings, feelings we do not readily admit to and often don't even recognize.

Chapter 2

Lessons from the Heart

O
N A SPRING AFTERNOON
several years ago, Evan McKinley was hiking in the woods near Halifax, Nova Scotia, when a pain in his chest stopped him in his tracks. McKinley was a forest ranger in his early forties, trim and extremely fit, with straw-blond hair and chiseled features. He had had a growing discomfort in his chest for the past few days, but nothing as severe as this. He wasn't sweating or lightheaded, and didn't feel feverish. But each time he took a breath, the pain got worse. McKinley slowly made his way back through the woods to the shed that housed his office. He sat and waited for the pain to pass, but it didn't. As a forest ranger, he was used to muscle aches from scaling a steep rocky trail or jogging with a loaded pack on his back. But this was different, and he decided he should see a doctor immediately.

As it happened, Dr. Pat Croskerry was working in the emergency department that day. He took McKinley's measure: a wiry, muscular man wearing the distinctive bright olive bomber jacket and pants, much like an American park ranger's uniform. McKinley's face was ruddy, as would be expected of someone who spends most of his day working outdoors, and his brow was free of per spiration. Croskerry listened intently as McKinley described how his chest pains had increased over the past few days and how they had worsened today. Croskerry questioned him further to get a more precise description of his symptoms. McKinley said the pains stayed in the center of his chest but did not move down his arms, into his neck, or through to his back. The pain got no worse if he changed position, and even taking a really deep breath didn't make him feel faint.

Croskerry went over a checklist of risk factors for heart and lung disease. McKinley had never smoked and had no family history of heart attack, stroke, or diabetes. He laughed, as Croskerry did, when Croskerry used the term "sedentary lifestyle." McKinley added that he felt under no particular stress, his family life was fine and he loved his job, and he had never been overweight. Croskerry then did a physical examination. First he verified that the vital signs recorded by the triage nurse were correct. McKinley's blood pressure was 110 over 60, his pulse 60 and regular, as would be expected of an athletic man. Croskerry listened with particular care to McKinley's lungs and heart, especially when he took a deep breath, but everything sounded fine. His muscles were well developed, and when Croskerry pressed on the junction between McKinley's ribs and breastbone, McKinley felt no pain. There was no swelling or tenderness in his calves or thighs. Finally, the doctor ordered an electrocardiogram, a chest x-ray, and blood work that would include tests for oxygen level and cardiac enzymes that indicate heart damage. As he expected, all of these were normal.

"I'm not at all worried about your chest pain," Croskerry told McKinley. "You probably overexerted yourself in the field and strained some muscle. My suspicion for this coming from your heart is about zero." Deeply reassured, the forest ranger went home.

The next morning, Croskerry was off duty, and read part of a novel that he was keen to finish. He is an avid athlete and rowed on Canada's 1976 Olympic crew in Montreal. He stays in shape, and that day he had jogged four miles around the Halifax harbor. When he arrived in the emergency department in the early evening, he bumped into a colleague. "Very interesting case, that man you saw yesterday," the doctor said. "He came in this morning with an acute myocardial infarction."

Croskerry was stunned. He reviewed his notes on the emergency room chart. The colleague tried to reassure him. "If I had seen this guy, I wouldn't have gone as far as you did in ordering all those tests." But Croskerry found this cold comfort. It was not because he expected to be infallible. Rather, he recognized that he had made a common cognitive error that could have cost the forest ranger his life. "Clearly, I missed it," Croskerry told me after recounting McKinley's case. "And why did I miss it? I didn't miss it because of any egregious behavior or negligence. I missed it because my thinking was overinfluenced by how healthy this man looked." Croskerry's voice faltered for a moment. "Happily, he didn't die."

Chest pain is the second most common reason for a patient to visit an emergency room (abdominal pain is number one). Each year in the United States and Canada there are more than six million evaluations in the ER of patients like McKinley. But despite its frequency, chest pain is one of the most challenging symptoms for the clinician to unravel. In retrospect, Croskerry realized that when he saw Evan McKinley, the ranger was in the midst of unstable angina—a crescendo of chest pain, caused by coronary artery disease, that usually prefigures a heart attack. "The unstable angina didn't show on the EKG, because fifty percent of such cases don't," Croskerry said in a voice that sounded to me as if he were lecturing himself. "His unstable angina did not show up on the cardiac enzymes because there wasn't yet injury to the heart muscle, and it didn't show up on the chest x-ray because the heart had not yet begun to fail to pump blood, so there was no fluid backup into the lungs."

The mistake Croskerry made is called a representativeness error: your thinking is guided by a prototype, so you fail to consider possibilities that contradict the prototype and thus attribute the symptoms to the wrong cause. Croskerry told me how his eyes had fixed on McKinley's trim frame and his elegant olive uniform, and how the ranger's physique and chiseled features reminded him of a young Clint Eastwood—all strong associations with health and vigor. Yes, there were unusual aspects to McKinley's angina; his pain was not typical of coronary artery disease, nor did the physical examination and tests point to the heart. But, Croskerry emphasized, that was precisely the point: "You have to be prepared in your mind for the atypical and not so quickly reassure yourself, and your patient, that everything is okay." When Croskerry now teaches students and interns about such errors, he uses Evan McKinley as an example.

More commonly, doctors make what are called attribution errors when patients fit a negative stereotype. Dr. Donald Redelmeier of the University of Toronto, who, like Croskerry, studies physician cognition, told me about a case he had recently seen on rounds. Charles Carver was in his seventies, retired from the merchant marine and living by himself in a small apartment. Over the past months, he had felt fatigued and his belly had begun to swell. When Carver came into the ER, the intern noticed alcohol on his breath, and Carver readily told him that he enjoyed a glass of rum each evening. His legs and feet, as well as his abdomen, were swollen. Carver was unshaven; his clothes were old and frayed. The intern wondered to himself how many days it had been since he bathed.

The initial presentation to Dr. Redelmeier on rounds was terse. "Charles Carver, a seventy-three-year-old retired merchant mariner, with a long history of alcohol ingestion, presents with in creasing fatigue and fluid retention." The intern palpated Carver's liver and told Redelmeier that it was enlarged, hard, and nodular. Redelmeier began to quiz the intern about Carver's problem. It soon became apparent that the trainee had in mind one and only one possible diagnosis: alcoholic cirrhosis. Redelmeier asked the medical team to offer other explanations for Carver's problems. He could see in their eyes that they felt burdened, that he was wasting precious time on rounds when they could be discussing much more interesting cases than that of an old, foul-smelling, rum-swilling sailor. "The intern's plan was to have this boozer sleep it off, give him some mild diuretics, and send him home as quickly as possible," Redelmeier told me.

"You are filled with a sense of disgust," Redelmeier said when we discussed the kinds of feelings that a man like Charles Carver summons in a doctor. That disgust pushes you away from him. Of course, as a doctor, it is your job to diagnose and treat him properly, but, consciously or subconsciously, you want to get the job over with and send such a man on his way. In particular, doctors consider people who seem not to be caring for themselves—alcoholics with cirrhosis, heavy smokers with end-stage emphysema, massively obese people with diabetes—as to some degree less deserving of their time and attention. Or, as in the stereotype of psychiatric patients that cloaked Anne Dodge, people who are not to be believed when they say they are following the doctor's orders. Physicians like to succeed in their treatment, and an essential ingredient for that success is a patient's cooperation. One doctor told me that patients who don't care for themselves made him feel like Sisyphus.

Redelmeier himselfis prone to that visceral sense of disgust. He has taught himself to recognize the feeling and, as he put it, "plant a red flag in my mind." So, on rounds that day, Redelmeier didn't back down. He pushed the interns and residents to come up with alternative hypotheses for Carver's liver disease. He insisted on tests for unusual conditions, like alpha-I antitrypsin deficiency, an inherited malady that can cause lung and liver disease, and Wilson's disease, another inherited disorder, in which copper deposits damage the liver and brain.

To everyone's surprise, including Redelmeier's, Charles Carver had Wilson's disease. "They said I was a brilliant clinician," Redelmeier recalled with a chuckle. "But it wasn't really brilliance. It was just forcing myself not to make an attribution error and dismiss the case out of hand as one more scuzzy alcoholic." Redelmeier added that, in fact, Carver was not an alcoholic. He enjoyed his glass of rum a day, but it really was only one glass, as Carver's daughter confirmed. Now, along with his evening drink, Carver takes copper chelators, drugs that remove the excess metal from his tissues.