Chapter 001. The Practice of Medicine

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The Modern-Day Physician

No greater opportunity, responsibility, or obligation can fall to the lot of a human being than to become a physician. In the care of the suffering, [the physician] needs technical skill, scientific knowledge, and human understanding. . . . Tact, sympathy, and understanding are expected of the physician, for the patient is no mere collection of symptoms, signs, disordered functions, damaged organs, and disturbed emotions. [The patient] is human, fearful, and hopeful, seeking relief, help, and reassurance.

–Harrison's Principles of Internal Medicine, 1950

The practice of medicine has changed in significant ways since the first edition of this book appeared in 1950. The advent of molecular biology with its enormous implications for the biological sciences (the sequencing of the human genome), sophisticated new imaging techniques, and advances in bioinformatics and information technology have contributed to an explosion of scientific information that has fundamentally changed the way we define, diagnose, treat, and prevent disease. This explosion of scientific knowledge is not at all static as it continues to intensify with time.

The widespread use of electronic medical records and the Internet have altered the way we practice medicine and exchange information. As today's physician struggles to integrate the copious amounts of scientific knowledge into everyday practice, it is important to remember that the ultimate goal of medicine is to treat the patient. Despite more than 50 years of scientific advances since the first edition of this text, it is critical to underscore that cultivating the intimate relationship that exists between physician and patient still lies at the heart of successful patient care.

The Science and ART of Medicine

Science-based technology and deductive reasoning form the foundation for the solution to many clinical problems. Spectacular advances in biochemistry, cell biology, and genomics, coupled with newly developed imaging techniques, allow access to the innermost parts of the cell and provide a window to the most remote recesses of the body. Revelations about the nature of genes and single cells have opened the portal for formulating a new molecular basis for the physiology of systems. Increasingly, we are understanding how subtle changes in many different genes can affect the function of cells and organisms. We are beginning to decipher the complex mechanisms by which genes are regulated. We have developed a new appreciation of the role of stem cells in normal tissue function and in the development of cancer, degenerative disease, and other disorders. The knowledge gleaned from the science of medicine has already improved and undoubtedly will further improve our understanding of complex disease processes and provide new approaches to disease treatment and prevention. Yet skill in the most sophisticated application of laboratory technology and in the use of the latest therapeutic modality alone does not make a good physician.

When a patient poses challenging clinical problems, an effective physician must be able to identify the crucial elements in a complex history and physical examination, to order the appropriate laboratory tests, and to extract the key results from the crowded computer printouts of data to determine whether to "treat" or to "watch." Deciding whether a clinical clue is worth pursuing or should be dismissed as a "red herring" and weighing whether a proposed treatment entails a greater risk than the disease itself are essential judgments that the skilled clinician must make many times each day. This combination of medical knowledge, intuition, experience, and judgment defines the art of medicine, which is as necessary to the practice of medicine as is a sound scientific base.

Clinical Skills

History-Taking

The written history of an illness should include all the facts of medical significance in the life of the patient. Recent events should be given the most attention. The patient should, at some early point, have the opportunity to tell his or her own story of the illness without frequent interruption and, when appropriate, receive expressions of interest, encouragement, and empathy from the physician. Any event related by the patient, however trivial or seemingly irrelevant, may provide the key to solving the medical problem. In general, only patients who feel comfortable will offer complete information, and thus putting the patient at ease to the greatest extent possible contributes substantially to obtaining an adequate history.

An informative history is more than an orderly listing of symptoms; by listening to patients and noting the way in which they describe their symptoms, physicians can gain valuable insight into the problem. Inflections of voice, facial expression, gestures, and attitude, i.e., "body language," may reveal important clues to the meaning of the symptoms to the patient. Because patients vary in their medical sophistication and ability to recall facts, the reported medical history should be corroborated whenever possible. The social history can also provide important insights into the types of diseases that should be considered. The family history not only identifies rare Mendelian disorders within a family but often reveals risk factors for common disorders such as coronary heart disease, hypertension, or asthma. A thorough family history may require input from multiple relatives to ensure completeness and accuracy. However, once recorded, it can be readily updated. The process of history-taking provides an opportunity to observe the patient's behavior and to watch for features to be pursued more thoroughly during the physical examination.

The very act of eliciting the history provides the physician with the opportunity to establish or enhance the unique bond that forms the basis for the ideal patient-physician relationship. This process helps the physician develop an appreciation of the patient's perception of the illness, the patient's expectations of the physician and the health care system, and the financial and social implications of the illness to the patient. Although current health care settings may impose time constraints on patient visits, it is important not to rush the history-taking since the patient may get the impression that what he or she is relating is not of importance to the physician and therefore may hold back relevant information. The confidentiality of the patient-physician relationship cannot be overemphasized.

Physical Examination

The purpose of the physical examination is to identify the physical signs of disease. The significance of these objective indications of disease is enhanced when they confirm a functional or structural change already suggested by the patient's history. At times, however, the physical signs may be the only evidence of disease.

The physical examination should be performed methodically and thoroughly, with consideration for the patient's comfort and modesty. Although attention is often directed by the history to the diseased organ or part of the body, the examination of a new patient must extend from head to toe in an objective search for abnormalities. Unless the physical examination is systematic and performed in a consistent manner from patient to patient, important segments may be inadvertently omitted. The results of the examination, like the details of the history, should be recorded at the time they are elicited, not hours later when they are subject to the distortions of memory. Skill in physical diagnosis is acquired with experience, but it is not merely technique that determines success in eliciting signs of disease. The detection of a few scattered petechiae, a faint diastolic murmur, or a small mass in the abdomen is not a question of keener eyes and ears or more sensitive fingers, but of a mind alert to these findings. Because physical findings can change with time, the physical examination should be repeated as frequently as the clinical situation warrants. Because a large number of highly sensitive diagnostic tests are available, particularly imaging techniques, it may be tempting to put less emphasis on the physical examination. Indeed, many patients are seen for the first time after a series of diagnostic tests have already been performed and the results known. This should not deter the physician from performing a thorough physical examination since clinical findings are often present that have "escaped" the barrage of preexamination diagnostic tests.

Diagnostic Studies

We have become increasingly reliant on a wide array of laboratory tests to solve clinical problems. However, accumulated laboratory data do not relieve the physician from the responsibility of carefully observing, examining, and studying the patient. It is also essential to appreciate the limitations of diagnostic tests. By virtue of their impersonal quality, complexity, and apparent precision, they often gain an aura of authority regardless of the fallibility of the tests themselves, the instruments used in the tests, and the individuals performing or interpreting them. Physicians must weigh the expense involved in the laboratory procedures relative to the value of the information they are likely to provide.

Single laboratory tests are rarely ordered. Rather, physicians generally request "batteries" of multiple tests, which often prove useful. For example, abnormalities of hepatic function may provide the clue to such nonspecific symptoms as generalized weakness and increased fatigability, suggesting the diagnosis of chronic liver disease. Sometimes a single abnormality, such as an elevated serum calcium level, points to a particular disease, such as hyperparathyroidism or underlying malignancy.

The thoughtful use of screening tests, such as low-density lipoprotein cholesterol, may be quite useful. A group of laboratory determinations can be carried out conveniently on a single specimen at relatively low cost. Screening tests are most informative when directed toward common diseases or disorders and when their results indicate the need for other useful tests or interventions that may be costly to perform. On the one hand, biochemical measurements, together with simple laboratory examinations such as blood count, urinalysis, and sedimentation rate, often provide a major clue to the presence of a pathologic process. On the other hand, the physician must learn to evaluate occasional abnormalities among the screening tests that may not necessarily connote significant disease. An in-depth workup following a report of an isolated laboratory abnormality in a person who is otherwise well is almost invariably wasteful and unproductive. Among the more than 40 tests that are routinely performed as screening, it would not be unusual for one or two of them to be slightly abnormal. If there is no suspicion of an underlying illness, these tests are ordinarily repeated to ensure that the abnormality does not represent a laboratory error. If an abnormality is confirmed, it is important to consider its potential significance in the context of the patient's condition and other test results.

The development of technically improved imaging studies with greater sensitivity and specificity is one of the most rapidly advancing areas of medicine. These tests provide remarkably detailed anatomic information that can be a pivotal factor in medical decision-making. Ultrasonography, a variety of isotopic scans, CT, MRI, and positron emission tomography have benefited patients by supplanting older, more invasive approaches and opening new diagnostic vistas. Cognizant of their capabilities and the rapidity with which they can lead to a diagnosis, it is tempting to order a battery of imaging studies. All physicians have had experiences in which imaging studies turned up findings leading to an unexpected diagnosis. Nonetheless, patients must endure each of these tests, and the added cost of unnecessary testing is substantial. A skilled physician must learn to use these powerful diagnostic tools judiciously, always considering whether the results will alter management and benefit the patient.

Principles of Patient Care

Evidence-Based Medicine

Evidence-based medicine refers to the concept that clinical decisions are formally supported by data, preferably data that are derived from prospectively designed, randomized, controlled clinical trials. This is in sharp contrast to anecdotal experience, which may often be biased. Unless they are attuned to the importance of using larger, more objective studies for making decisions, even the most experienced physicians can be influenced by recent encounters with selected patients. Evidence-based medicine has become an increasingly important part of the routine practice of medicine and has led to the publication of a number of practice guidelines.

Practice Guidelines

Professional organizations and government agencies are developing formal clinical-practice guidelines to aid physicians and other caregivers in making diagnostic and therapeutic decisions that are evidence-based, cost-effective, and most appropriate to a particular patient and clinical situation. As the evidence base of medicine increases, guidelines can provide a useful framework for managing patients with particular diagnoses or symptoms. They can protect patients—particularly those with inadequate health care benefits—from receiving substandard care. Guidelines can also protect conscientious caregivers from inappropriate charges of malpractice and society from the excessive costs associated with the overuse of medical resources. There are, however, caveats associated with clinical practice guidelines since they tend to oversimplify the complexities of medicine. Furthermore, groups with differing perspectives may develop divergent recommendations regarding issues as basic as the need for periodic sigmoidoscopy in middle-aged persons. Finally, guidelines do not—and cannot be expected to—account for the uniqueness of each individual and his or her illness. The physician's challenge is to integrate into clinical practice the useful recommendations offered by experts without accepting them blindly or being inappropriately constrained by them.

Medical Decision-Making

Medical decision-making is an important responsibility of the physician and occurs at each stage of the diagnostic and treatment process. It involves the ordering of additional tests, requests for consults, and decisions regarding treatment and prognosis. This process requires an in-depth understanding of the pathophysiology and natural history of disease. As described above, medical decision-making should be evidence-based so that patients derive the full benefit of the scientific knowledge available to physicians. Formulating a differential diagnosis requires not only a broad knowledge base but also the ability to assess the relative probabilities of various diseases. Application of the scientific method, including hypothesis formation and data collection, is essential to the process of accepting or rejecting a particular diagnosis. Analysis of the differential diagnosis is an iterative process. As new information or test results are acquired, the group of disease processes being considered can be contracted or expanded appropriately.

Despite the importance of evidence-based medicine, much of medical decision-making relies on good clinical judgment—a process that is difficult to quantify or even to assess qualitatively. Physicians must use their knowledge and experience as a basis for weighing known factors along with the inevitable uncertainties and the need to use sound judgment; this is particularly important when a relevant evidence base is not available. Several quantitative tools may be invaluable in synthesizing the available information, including diagnostic tests, Bayes' theorem, and multivariate statistical models. Diagnostic tests serve to reduce uncertainty about a diagnosis or prognosis in a particular individual and to help the physician decide how best to manage that individual's condition. The battery of diagnostic tests complements the history and the physical examination. The accuracy of a given test is ascertained by determining its sensitivity (true positive rate) and specificity (true negative rate) as well as the predictive value of a positive and negative result. Bayes' theorem uses information on a test's sensitivity and specificity, in conjunction with the pretest probability of a diagnosis, to determine mathematically the posttest probability of the diagnosis. More complex clinical problems can be approached with multivariate statistical models, which generate highly accurate information even when multiple factors are acting individually or together to affect disease risk, progression, or response to treatment. Studies comparing the performance of statistical models with that of expert clinicians have documented equivalent accuracy, although the models tend to be more consistent. Thus, multivariate statistical models may be particularly helpful to less experienced clinicians. See Chap. 3 for a more thorough discussion of decision-making in clinical medicine.

Electronic Medical Records

Our growing reliance on computers and the strength of information technology are playing an increasingly important role in medicine. Laboratory data are accessed almost universally through computers. Many medical centers now have electronic medical records, computerized order entry, and bar-coded tracking of medications. Some of these systems are interactive and provide reminders or warn of potential medical errors. In many ways, the health care system has lagged behind other industries in the adoption of information technology. Electronic medical records have extraordinary potential for providing rapid access to clinical information, imaging studies, laboratory results, and medications. This type of information is invaluable for ongoing efforts to enhance quality and improve patient safety. Ideally, patient records should be easily transferred across the health care system, providing reliable access to relevant data and historic information. However, technology limitations and concerns about privacy and cost continue to limit a broad-based utilization of electronic health records in most clinical settings. It should also be emphasized that information technology is merely a tool and can never replace the clinical decisions that are best made by the physician. In this regard, clinical knowledge and an understanding of the patient's needs, supplemented by quantitative tools, still seem to represent the best approach to decision-making in the practice of medicine.

Evaluation of Outcomes

Clinicians generally use objective and readily measurable parameters to judge the outcome of a therapeutic intervention. For example, findings on physical or laboratory examination—such as the blood pressure level, the patency of a coronary artery on an angiogram, or the size of a mass on a radiologic examination—can provide critically important information. However, patients usually seek medical attention for subjective reasons; they wish to obtain relief from pain, to preserve or regain function, and to enjoy life. The components of a patient's health status or quality of life can include bodily comfort, capacity for physical activity, personal and professional function, sexual function, cognitive function, and overall perception of health. Each of these important areas can be assessed by means of structured interviews or specially designed questionnaires. Such assessments also provide useful parameters by which the physician can judge the patient's subjective view of his or her disability and the response to treatment, particularly in chronic illness. The practice of medicine requires consideration and integration of both objective and subjective outcomes.

Women's Health and Disease

Although past epidemiologic studies and clinical trials have often focused predominantly on men, more recent studies have included more women, and some, like the Women's Health Initiative, have exclusively addressed women's health issues. Significant gender differences exist in diseases that afflict both men and women. Much is still to be learned in this arena, and ongoing studies should enhance our understanding of the mechanisms of gender differences in the course and outcome of certain diseases. For a more complete discussion of women's health, see Chap. 6.

Care of the Elderly

The relative proportion of elderly individuals in the populations of developed nations has been growing considerably over the past few decades and will continue to grow. In this regard, the practice of medicine will continue to be greatly influenced by the health care needs of this growing elderly population. The physician must understand and appreciate the decline in physiologic reserve associated with aging; the diminished responses of the elderly to vaccinations such as those against influenza; the different responses of the elderly to common diseases; and disorders that occur commonly with aging, such as depression, dementia, frailty, urinary incontinence, and fractures. For a more complete discussion of medical care for the elderly, see Chap. 9.

Errors in the Delivery of Health Care

A report from the Institute of Medicine called for an ambitious agenda to reduce medical-error rates and improve patient safety by designing and implementing fundamental changes in health care systems. Adverse drug reactions occur in at least 5% of hospitalized patients, and the incidence increases with use of a large number of drugs. No matter what the clinical situation, it is the responsibility of the physician to use powerful therapeutic measures wisely, with due regard for their beneficial action, potential dangers, and cost. It is also the responsibility of hospitals and health care organizations to develop systems to reduce risk and ensure patient safety. Medication errors can be reduced through the use of ordering systems that eliminate misreading of handwriting. Implementation of infection-control systems, enforcement of hand-washing protocols, and careful oversight of antibiotic use can minimize complications of nosocomial infections.

The Role of the Physician in the Informed Consent of the Patient

The fundamental principles of medical ethics require physicians to act in the patient's best interest and to respect the patient's autonomy. This is particularly relevant to the issue of informed consent. Most patients possess only limited medical knowledge and must rely on their physicians for advice. Physicians must respect their patients' autonomy, fully discussing the alternatives for care and the risks, benefits, and likely consequences of each alternative.

Patients are required to sign a consent form for essentially any diagnostic or therapeutic procedure. In such cases, it is particularly important for the patient to understand clearly the risks and benefits of these procedures; this is the definition of informed consent. It is incumbent on the physician to explain the procedures in a clear and understandable manner and to ascertain that the patient comprehends both the nature of the procedure and the attendant risks and benefits. The dread of the unknown, inherent in hospitalization, can be mitigated by such explanations.

The Approach to Grave Prognoses and Death

No problem is more distressing than the diagnosis of an incurable disease, particularly when premature death is inevitable. What should the patient and family be told? What measures should be taken to maintain life? What can be done to maintain the quality of life?

Although some would argue otherwise, there is no ironclad rule that the patient must immediately be told "everything," even if the patient is an adult with substantial family responsibilities. How much is told at a given point in time should depend on the individual's ability to deal with the possibility of imminent death; often this capacity grows with time, and, whenever possible, gradual rather than abrupt disclosure is the best strategy. A wise and insightful physician is often guided by an understanding of what a patient wants to know and when he or she wants to know it. The patient's religious beliefs may also be taken into consideration. The patient must be given an opportunity to talk with the physician and ask questions. Patients may find it easier to share their feelings about death with their physician, who is likely to be more objective and less emotional, than with family members. As William Osler wrote, "One thing is certain; it is not for you to don the black cap and, assuming the judicial function, take hope away from any patient." Even when the patient directly inquires, "Am I dying?" the physician must attempt to determine whether this is a request for information or for reassurance. Only open communication between the patient and the physician can resolve this question and guide the physician in what to say and how to say it.

The physician should provide or arrange for emotional, physical, and spiritual support and must be compassionate, unhurried, and open. There is much to be gained by the laying on of hands. Pain should be adequately controlled, human dignity maintained, and isolation from family and close friends avoided. These aspects of care tend to be overlooked in hospitals, where the intrusion of life-sustaining apparati can so easily detract from attention to the whole person and encourage concentration instead on the life-threatening disease, against which the battle will ultimately be lost in any case. In the face of terminal illness, the goal of medicine must shift from cure to care, in the broadest sense of the term. In offering care to the dying patient, the physician must be prepared to provide information to family members and to deal with their grief and sometimes their feelings of guilt. It is important for the doctor to assure the family that everything possible has been done. For a more complete discussion of end-of-life care, see Chap. 11.

The Patient-Physician Relationship

The significance of the intimate personal relationship between physician and patient cannot be too strongly emphasized, for in an extraordinarily large number of cases both the diagnosis and treatment are directly dependent on it. One of the essential qualities of the clinician is interest in humanity, for the secret of the care of the patient is in caring for the patient.

–Francis W. Peabody, 1881–1927

Physicians must never forget that patients are individual human beings with problems that all too often transcend their physical complaints. They are not "cases" or "admissions" or "diseases." This point is particularly important in this era of high technology in clinical medicine. Most patients are anxious and fearful. Physicians should instill confidence and should be reassuring but should never be arrogant. A professional attitude, coupled with warmth and openness, can do much to alleviate anxiety and to encourage patients to share all aspects of their medical history. Whatever the patient's attitude, the physician needs to consider the setting in which an illness occurs—in terms not only of the patients themselves but also of their familial, social, and cultural backgrounds. The ideal patient-physician relationship is based on thorough knowledge of the patient, on mutual trust, and on the ability to communicate.

The Dichotomy of Inpatient and Outpatient Internal Medicine

The hospital environment has transformed dramatically over the past few decades. In more recent times, emergency departments and critical care units have evolved to identify and manage critically ill patients, allowing them to survive formerly fatal diseases. There is increasing pressure to reduce the length of stay in the hospital and to manage complex disorders in the outpatient setting. This transition has been driven not only by efforts to reduce costs but also by the availability of new outpatient technologies, such as imaging and percutaneous infusion catheters for long-term antibiotics or nutrition, and by evidence that outcomes are often improved by minimizing inpatient hospitalization. Hospitals now consist of multiple distinct levels of care, such as the emergency department, procedure rooms, overnight observation units, critical care units, and palliative care units, in addition to traditional medical beds. A consequence of this differentiation has been the emergence of new specialties such as emergency medicine, intensivists, hospitalists, and end-of-life care. Moreover, these systems frequently involve "hand-offs" from the outpatient to the inpatient environment, from the critical care unit to a general medicine floor, and from the hospital to the outpatient environment. Clearly, one of the important challenges in internal medicine is to maintain continuity of care and information flow during these transitions, which threaten the traditional one-to-one relationship between patient and physician. In the current environment, teams of physicians, specialists, and other health care professionals have often replaced the personal interaction between doctor and patient. The patient can benefit greatly from effective collaboration among a number of health care professionals; however, it is the duty of the patient's principal or primary physician to provide cohesive guidance through an illness. In order to meet this challenge, the primary physician must be familiar with the techniques, skills, and objectives of specialist physicians and allied health professionals. The primary physician must ensure that the patient will benefit from scientific advances and from the expertise of specialists when they are needed, while still retaining responsibility for the major decisions concerning diagnosis and treatment.

Appreciation of the Patient's Hospital Experience

The hospital is an intimidating environment for most individuals. Hospitalized patients find themselves surrounded by air jets, buttons, and glaring lights; invaded by tubes and wires; and beset by the numerous members of the health care team—nurses, nurses' aides, physicians' assistants, social workers, technologists, physical therapists, medical students, house officers, attending and consulting physicians, and many others. They may be transported to special laboratories and imaging facilities replete with blinking lights, strange sounds, and unfamiliar personnel; they may be left unattended for periods of time; they may be obliged to share a room with other patients who have their own health problems. It is little wonder that patients may lose their sense of reality. Physicians who can appreciate the hospital experience from the patient's perspective and make an effort to develop a strong personal relationship with the patient whereby they may guide the patient through this experience can make a stressful situation more tolerable.

Trends in the Delivery of Health Care: A Challenge to the Humane Physician

Many trends in the delivery of health care tend to make medical care impersonal. These trends, some of which have been mentioned already, include (1) vigorous efforts to reduce the escalating costs of health care; (2) the growing number of managed-care programs, which are intended to reduce costs but in which the patient may have little choice in selecting a physician or in seeing that physician consistently; (3) increasing reliance on technological advances and computerization for many aspects of diagnosis and treatment; (4) the need for numerous physicians to be involved in the care of most patients who are seriously ill; and (5) an increased number of malpractice suits, some of which are justifiable because of medical errors, but others of which reflect an unrealistic expectation on the part of many patients that their disease will be cured or that complications will not occur during the course of complex illnesses or procedures.

Given these changes in the medical care system, it is a major challenge for physicians to maintain the humane aspects of medical care. The American Board of Internal Medicine, working together with the American College of Physicians–American Society of Internal Medicine and the European Federation of Internal Medicine, has published a Charter on Medical Professionalism that underscores three main principles in physicians' contract with society: (1) the primacy of patient welfare, (2) patient autonomy, and (3) social justice. Medical schools have also increased their emphasis on physician professionalism in recent years (Fig. 1-1). The humanistic qualities of a physician must encompass integrity, respect, and compassion. Availability, the expression of sincere concern, the willingness to take the time to explain all aspects of the illness, and a nonjudgmental attitude when dealing with patients whose cultures, lifestyles, attitudes, and values differ from those of the physician are just a few of the characteristics of the humane physician. Every physician will, at times, be challenged by patients who evoke strongly negative or positive emotional responses. Physicians should be alert to their own reactions to such patients and situations and should consciously monitor and control their behavior so that the patient's best interest remains the principal motivation for their actions at all times.
An important aspect of patient care involves an appreciation of the patient's "quality of life," a subjective assessment of what each patient values most. Such an assessment requires detailed, sometimes intimate knowledge of the patient, which can usually be obtained only through deliberate, unhurried, and often repeated conversations. Time pressures will always threaten these interactions, but they should not diminish the importance of understanding and seeking to fulfill the priorities of the patient.

The Twenty-First Century Physician: Expanding Frontiers

The Era of Genomics

In the spring of 2003, the complete sequencing of the human genome was announced, officially ushering in the genomic era. However, even before this landmark accomplishment, the practice of medicine had been evolving as a result of the insights gained from an understanding of the human genome as well as the genomes of a wide variety of microbes, whose genetic sequences were becoming widely available as a result of the breathtaking advances in sequencing techniques and informatics. Examples of the latter include the identification of a novel coronavirus as the etiologic agent of the severe acute respiratory syndrome (SARS) and the tracking of the evolution of a potentially pandemic influenza virus found in birds. Today, gene expression profiles are being used to guide therapy and inform prognosis for a number of diseases; the use of genotyping is providing a new means to assess the risk of certain diseases as well as variation in response to a number of drugs; we are understanding better the role of certain genes in the causality of certain common conditions such as obesity and allergies. Despite these advances, we are still in the infancy of understanding and utilizing the complexities of genomics in the diagnosis, prevention, and treatment of disease. Our task is complicated by the fact that phenotypes are generally determined not by genes alone but by the interplay of genetic and environmental factors. Indeed, we have just begun to scratch the surface of possibilities that the era of genomics will provide to the practice of medicine.

The rapidity of these advances may seem overwhelming to the practicing physician. However, he or she has an important role to play in ensuring that these powerful technologies and sources of new information are applied with sensitivity and intelligence to the patient. Since genomics is such a rapidly evolving field, physicians and other health care professionals must continue to educate themselves so that they can apply this new knowledge to the benefit of their patients' health and well-being. Genetic testing requires wise counsel based on an understanding of the value and limitations of the tests as well as the implications of their results for specific individuals. For a more complete discussion of genetic testing, see Chap. 64.

The Globalization of Medicine

Physicians should be cognizant of diseases and health care services beyond local boundaries. Global travel has implications for disease spread, and it is not uncommon for diseases endemic to certain regions to be seen in other regions after a patient has traveled and returned from these regions. Patients have broader access to unique expertise or clinical trials at distant medical centers, and the cost of travel may be offset by the quality of care at these distant locations. As much as any other factor influencing global aspects of medicine, the Internet has transformed the transfer of medical information throughout the world. This change has been accompanied by the transfer of technological skills through telemedicine and international consultation for radiologic images and pathologic specimens. For a complete discussion of global issues, see Chap. 2.

Medicine on the Internet

On the whole, the Internet has had a very positive effect on the practice of medicine; a wide range of information is available to physicians and patients through personal computers almost instantaneously at any time and from anywhere in the world. This medium holds enormous potential for delivering up-to-date information, practice guidelines, state-of-the-art conferences, journal contents, textbooks (including this text), and direct communications with other physicians and specialists, thereby expanding the depth and breadth of information available to the physician about the diagnosis and care of patients. Most medical journals are now accessible online, providing rapid and comprehensive sources of information. This medium also serves to lessen the information gap felt by physicians and health care providers in remote areas of the world by bringing them into direct and instant contact with the latest developments in medical care.

Patients, too, are turning to the Internet in increasing numbers to acquire information about their illnesses and therapies and to join Internet-based support groups. Physicians are increasingly faced with the prospect of dealing with patients who arrive with sophisticated information about their illness. In this regard, physicians are challenged in a positive way to keep themselves abreast of the latest relevant information while serving as an "editor" for the patients as they navigate through this seemingly endless source of information.

A critically important caveat is that virtually anything can be published on the Internet, with easy circumvention of the peer-review process that is an essential feature of quality publications. Physicians or patients who search the Internet for medical information must be aware of this danger. Notwithstanding this limitation, appropriate use of the Internet is revolutionizing information access for physicians and patients and in this regard is a great benefit that was not available to our predecessors.

Public Expectations and Accountability

The level of knowledge and sophistication regarding health issues on the part of the general public has grown rapidly over the past few decades. As a result, expectations of the health care system in general and of physicians in particular have risen. Physicians are expected to master rapidly advancing fields (the science of medicine) while considering their patients' unique needs (the art of medicine). Thus, physicians are held accountable not only for the technical aspects of the care that they provide but also for their patients' satisfaction with the delivery and costs of care.

In many parts of the world, physicians are increasingly expected to account for the way in which they practice medicine by meeting certain standards prescribed by federal and local governments. The hospitalization of patients whose health care costs are reimbursed by the government and other third parties is subjected to utilization review. Thus, the physician must defend the cause for and duration of a patient's hospitalization if it falls outside certain "average" standards. Authorization for reimbursement is increasingly based on documentation of the nature and complexity of an illness, as reflected by recorded elements of the history and physical examination. There is a growing "pay for performance" movement, which seeks to link reimbursement to quality of care. The goal of this movement is to improve standards of health care and to contain spiraling health care costs. Physicians are also expected to give evidence of their continuing competence through mandatory continuing education, patient-record audits, maintenance of certification, or relicensing.

Medical Ethics and New Technologies

The rapid pace of technological advances has profound implications for medical applications far beyond their traditional roles to prevent, treat, and cure disease. Cloning, genetic engineering, gene therapy, human-computer interfaces, nanotechnology, and designer drugs have the potential to modify inherited predispositions to disease, select desired characteristics in embryos, augment "normal" human performance, replace failing tissues, and substantially prolong life span. Because of their unique training, physicians have a responsibility to help shape the debate concerning the appropriate uses of, and limits that should be placed on, these new techniques.

The Physician as Perpetual Student

It becomes all too apparent from the time we graduate from medical school that as physicians our lot is that of the "perpetual student" and the mosaic of our knowledge and experiences is eternally unfinished. This concept can be at the same time exhilarating and anxiety-provoking. It is exhilarating because we will continue to expand our knowledge that can be applied to our patients; it is anxiety-provoking because we realize that we will never know as much as we want or need to know. At best, we will translate this latter feeling into energy to continue to improve ourselves and realize our potential as physicians. In this regard, it is the responsibility of a physician to pursue new knowledge continually by reading, attending conferences and courses, and consulting colleagues and the Internet. This is often a difficult task for a busy practitioner; however, such a commitment to continued learning is an integral part of being a physician and must be given the highest priority.

Research, Teaching, and the Practice of Medicine

The title doctor is derived from the Latin docere, "to teach," and physicians should share information and medical knowledge with colleagues, with students of medicine and related professions, and with their patients. The practice of medicine is dependent on the sum total of medical knowledge, which in turn is based on an unending chain of scientific discovery, clinical observation, analysis, and interpretation. Advances in medicine depend on the acquisition of new information through research, and improved medical care requires the transmission of this information. As part of broader societal responsibilities, the physician should encourage patients to participate in ethical and properly approved clinical investigations if they do not impose undue hazard, discomfort, or inconvenience. On the other hand, physicians engaged in clinical research must be alert to potential conflicts of interest between their research goals and their obligations to individual patients; the best interests of the patient must always take priority.

To wrest from nature the secrets which have perplexed philosophers in all ages, to track to their sources the causes of disease, to correlate the vast stores of knowledge, that they may be quickly available for the prevention and cure of disease—these are our ambitions.

–William Osler, 1849–1919

Further Readings
Blank L et al: Medical professionalism in the new millennium: A physician charter 15 months later. Ann Intern Med 138:839, 2003 [PMID: 12755556]

Council on Graduate Medical Education: Thirteenth Report: Physician Education for a Changing Health Care Environment. US Department of Health and Human Services, March 1999

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