(Circulation. 1995;91:2089-2092.)
© 1995 American Heart Association, Inc.
Articles |
Bedside Science Reduces Laboratory Art
Appropriate Use of Physical Findings to Reduce Reliance on Sophisticated and Expensive Methods
From the Albert Einstein College of Medicine, Research, Cardiology, Medical Center at Flushing, NY, and the Cardiology Division, University of Massachusetts, Medical School, St Vincent Hospital, Worcester, Mass.
Correspondence to Samuel Zoneraich, MD, 46th Ave, Flushing, NY 11355.
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Introduction |
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 Top Introduction Magnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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During recent decades, we have witnessed the steady downgrading of bedside cardiology as it is constantly being replaced by modern technology. Many, if not most, cardiological diagnoses could be made by use of patient history and the physical examination, supplemented by simple noninvasive procedures, such as the ECG and chest roentgenogram. Newer, increasingly complex techniques become indispensable only when the simpler methods fail or when physicians fail to use them appropriately owing to ignorance, lack of training, or atrophy of previously acquired skills. Access to more sophisticated technologies accelerates these trends in contemporary practice.
Newer diagnostic technologies expanded our ability to define anatomic and physiological abnormalities. Our clinical acumen was first sharpened by the correlation between bedside cardiology and cardiac catheterization. Newer, noninvasive confirmatory techniques, such as nuclear medicine, ultrasonography, computed tomography, and magnetic resonance imaging should have further extended and honed our clinical capabilities. Yet these impressive opportunities ultimately weakened transmission and acquisition of physical diagnostic skills. In 300 randomized subjects autopsied in 1960, 1970, and 1980, Harvard investigators reported that 20 years of sonography, scintigraphy, and computed tomography had not reduced the frequency of misdiagnosis.1
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Magnitude of the Problem |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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A nationwide investigation of trainees in internal medicine and cardiology and third-year medical students demonstrated that the proficiency of bedside cardiac auscultation was seriously degraded.2 Programs with structured teaching in auscultation existed in only 27% of medicine and 37% of cardiology programs.3 Correct answers at the end of an academic year ranged from 0% to 56% for cardiology fellows (median, 21.9%) and from 2% to 36.8% for medical residents (median, 19.3%); these performances equalled those of the third-year medical students.
In another survey, 124 internal medicine residents, 11 pulmonary fellows, and 63 medical students in six university-affiliated programs were never exposed to structured teaching of pulmonary auscultation. The auscultatory performance of medical residents was 13.7% to 82.3% (median, 51.6%). Their clinical skills, which failed to improve during customary training, were no better than those of medical students.4
Structured teaching of cardiac and pulmonary auscultation includes lectures; seminars; use of audiotapes, videotapes, and simulators; and bedside physical evaluation. Six hundred five residents in internal medicine and family medicine who were accredited in the United States and who responded to survey showed overwhelming interest in cardiac and pulmonary auscultation (5.5+ and 5.3±8, respectively, on a grade scale of 0 to 6).5 Most of the respondents interviewed thought that more auscultatory teaching was necessary during training (4.5±1.3 and 4.7±1.1). Structured teaching of cardiac auscultation was included in 23.1% and 27.1% of family medicine and internal medicine programs. Family medicine program directors requested more teaching of cardiac auscultation in the United States.5
A pilot study6 evaluated the clinical skills of medical students trained rurally (n=9) versus those trained in metropolitan medical centers (n=9). The rurally trained students spent more time with patients and collected more case-relevant data than their counterparts from the metropolitan medical centers. Therefore, one can assume that the cause of superior educational outcome of rural training should be given special consideration.
The In-Training Examination in Internal Medicine provides residents and program directors with a reliable evaluation of their level of competence and factual knowledge. It has the unique advantage of providing insight into the "working" knowledge of the house staff. However, as is the case with any other written examination, "the test does not measure bedside skills, residents' attitude or relationship with patients."7 It fails to evaluate teaching ability, technical skills, and humanistic qualities. Such characteristics are best evaluated by direct observation.
Contemporary teaching rounds often take place in the conference room and not at the bedside. Internal medicine topics are taught during lunch hours in conference rooms.8 Physical examinations cannot be evaluated by written certification examinations and therefore are considered by residents and fellows to be of no major significance.
Even teaching with Harvey simulators failed to improve house staff skills. At the end of an academic year, the house staff gave correct answers in 52% of patients with mitral regurgitation, in 37% of patients with mitral stenosis, and in 54% of patients with aortic regurgitation.9 In another study, errors occurred in 56.7% of the cardiac examinations performed by the house staff.10 Basic physical examination skills thus require basic improvement.11
Neglect of the inexpensive and indispensable ECG springs from the same trends as neglect of physical examination. Recent cardiovascular fellows are so poor at it that the time allotted to the ECG in the certifying board examination was expanded by 50%, ie, from 2 to 3 half-days. The third half-day is completely devoted to ordinary electrocardiography; fellows are required to pass this section irrespective of performance on the preceding traditional full day.
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Bedside Rounds: Science and Applications |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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Objective assessment of the ability of individual physicians to evaluate physical signs is lacking.12 We undertook this report to evaluate physician competency because we discovered that we took a similar approach to teaching and assessing clinical evidence; we both used a blinded approach to evaluation of the data to avoid information biases and misinformation. While our approaches had individual differences, essentially we each encourage trainees initially to provide us with access in a blinded fashion to the patient and the patient's test results. Thus, with the knowledge that we are dealing with cardiovascular problems, physical examination should reveal any such problems irrespective of patient history and laboratory findings. That is, if there is an abnormal heart sound, a murmur, or a palpatory abnormality, we should be able to find it without being directed or misdirected by additional information. For example, it is easy to note the absence of an
wave in the jugular pulse if one is
told that the patient has atrial fibrillation. Depending on the problem, the ECG or chest roentgenogram can be used by itself for diagnosis or after bedside evaluation. Indeed, some patients can be presented because of an unusual or particularly interesting ECG or chest roentgenogram, and these patients can be analyzed in the absence of other data, since what is present (that is, the evidence we see) is there, irrespective of other information.
Naturally, for all visual tests, reading and interpretation are different but related matters.
It is the reading that must be made cleanly. The interpretation, of course, as with the ultimate interpretation of physical findings, must await the gathering of all important data. However, for the most objective practice and for training purposes, all data initially must be evaluated in an unbiased manner. As Oliver Wendell Holmes recommended to his legal trainees: First get your facts and then distort them as you will.
Approaches comparable to the foregoing were adopted by well-known clinicians, such as Jean Lenègre and Charles Debray in Paris, France, Isadore Snapper and William Dressler in New York City, and Sodi-Pallares in Mexico City. William Dock could make correct diagnoses from physical examinations alone.13 He thought that "blinding" strengthens evidence for clinical diagnosis and "raises the feeling of confidence and self-esteem of the participant."
Key to improving any clinical skill is correction of faulty teaching methods, a problem that to some extent preceded the advent of sophisticated laboratory crutches. For example, ECG and chest roentgenogram readings are considered to require prior acquaintance with clinical and other data. This may be true of ultimate composite interpretation, but primary readings should report what is there in front of the reader: all the clinical truths, half truths, and untruths cannot add to or subtract from the visual evidence.
How many well-trained cardiologists could approach that standard? Similarly, if a physical finding exists, it is there irrespective of any other data (subject, of course, to observer variability). Atrial fibrillation usually can be diagnosed without prior inspection of an ECG. Without its occasional mimic, multifocal atrial tachycardia, atrial fibrillation is of course much easier to diagnose if one has already seen the ECG, which facilitates further atrophy of bedside skills.
The technique of taking a patient history, including a general inspection and personality assessment, can be considered as the most important part of the entire bedside examination.14 15 Grupper et al16 reported straightforward clinical diagnoses in 79% of internal medicine outpatients that were based only on the nurses' notes and patients' demographic information before even seeing the patients and in 90% of cases after adding the chief complaint and the patient history.16 Such findings confirm the significance of patient histories, including those taken by dedicated nurses in the outpatient department.
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Palpation and Auscultation |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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In 1876, Richard Schulz17 reported on the "diabetic" heart in 81 patients in whom the physical diagnosis was based on palpation and auscultation (faint S1) and realized that "[e]ach test must stand on its own merits." Palpation detects abnormalities of the apical impulse and ectopic precordial pulsations, such as precordial bulges in ischemic heart disease, a right ventricular impulse produced by right ventricular hypertrophy, palpable heart sounds and gallops, thrills, and aortic and pulmonary artery pulsation.
In this connection, it is remarkably poorly understood that a sensitive area for palpation is the palm just proximal to the fingers.18 Percussion is being used less often and by a limited number of physicians but has not been the subject of a truly objective investigation.
The stethoscope, introduced in 1819,19 endures as one of the physician's most indispensable medical tools. The sensitivity of the human hearing and cybernetics of the human brain offer a high level of effectiveness, as confirmed by modern technology. In contrast to the use of equipment handled by the technician, the physician, by imposing on himself uncompromising self-discipline and years of apprenticeship, lays the groundwork for a diagnosis based on his own findings. Physical examination, and auscultation in particular, continue to be of paramount importance in diagnosing rheumatic heart disease among sociopolitically deprived minorities in Western countries and among indigent third-world populations. For example, during a recent outbreak of rheumatic fever in the United States, 12 of 67 patients (18%) had acute carditis and 2 required mitral surgery. In South Africa,20 748 patients (median age, 25 years old) had mitral-valve surgery from 1983 through 1986. All these patients could have benefitted from diligent auscultation.
Recently, S3 was found to be the best predictor of mortality at 2.5 years in patients with coronary artery disease.21 22
Auscultation over the arteries is part of the routine physical examination. For example, auscultation of the abdomen over the aorta and its branches is used to assess vascular disorders.23 It is the first basic clue for evaluation of hypertensive renal disease.
The diagnostic value of cervical bruits as a marker distinguishing high-grade from moderately symptomatic carotid stenosis was evaluated in 1268 patients enrolled in NASCET, a randomized multicenter trial conducted in 57 centers across Canada and the United States from 1988 through 1991.24 Patient history and physical examination, including auscultation of the orbits, supraclavicular area, and neck, were compared with computed tomography and bilateral angiography. An ipsilateral carotid bruit had a sensitivity of 60% and a specificity of 61% for high-grade stenosis, but when combined with other findings characteristics, such as carotid ultrasound scan suggesting >90% stenosis, a transient ischemic attack, and a retinal event, the high-grade stenosis ranged to 94%.24 Hence, under some conditions, the physical findings require complementation. Cervical bruits were absent in one third of patients with high-grade stenosis. In our own experience, short systolic bruits were present in severe vascular renal stenosis (and, hence, are of clinical significance); the bruit was absent in complete obstruction of the artery.25
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Do Doppler Ultrasonography and Nuclear Magnetic Resonance Imaging Quantify Mitral Valvular Murmurs? |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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Disturbed flow that produces murmurs depends on many factors, including the driving pressure, jet-dimension orifice size, viscosity, multiple associated radial velocities, compliance of the receiving chamber, and the instrument variable.26 DeMaria et al found that the geometry of the regurgitant jet could not quantify the volume of the murmur. Doppler ultrasonography is extremely sensitive for detecting flow patterns that were considered to be the result of cardiac abnormalities. However, Houston27 has reported that some abnormalities appeared to be normal variants. The original enthusiasm for quantification of mitral valve murmurs has simmered down to a more realistic goal: semiquantification.28 Quantification of mitral regurgitation by nuclear magnetic resonance imaging is facing the same limitations: lack of a precise reference standard to compare the result of velocity-encoded cine imaging, lack of discrimination between patients with mild regurgitation and normal subjects, and signals without artifacts emanating from sternal wires.29
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Supportive Role of Inexpensive Techniques |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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ECG
Einthoven's ECG, which was introduced 90 years ago, remains a powerful diagnostic tool for supplementing bedside information. It offers diagnostic clues to anatomic, hemodynamic, metabolic, and therapeutic interventions. Identification of subtle changes in ECG and thorough recognition of the limitations of ECG remain the privilege of the well informed.30 Only in exceptional cases will the echocardiogram make the correct diagnosis of atrial flutter rather than the ECG.31
In some patients, the surface ECG remains an independent marker for coronary artery disease. Modern technical advances, such as surface and intracardiac mapping and His-bundle ECGs, have strengthened the diagnostic value of the surface ECG. The need for recording the intracardiac ECG is often eliminated by "careful assessment of the surface ECG."32 Bedside diagnosis of ischemic heart disease is definitely strengthened by stress testing.
Computers are of little value for diagnosing cardiac arrhythmias and in other conditions. For all practical purposes, an experienced cardiologist validates the computer reading. Individual physicians should be able to correlate ECG findings with bedside patient examination. Frequently, when the ECG offers borderline information or is nonspecific, use of the ECG is inseparable from clinical observation for diagnosis. For example, among the fine points of diagnosing coronary artery disease, straightening of the ST segment producing a right angle is a valuable clue missed by the computer.
Another example in the continual discovery of new information in the standard ECG is that newer and previously unrecognized minor ECG markers are now considered helpful for diagnosing long QT syndrome. The long QT syndrome trait is considered present even among blood relatives with borderline QTc intervals. In such families, T-wave "humps" involving left precordial leads or limb leads ought to be considered part of the QT-syndrome trait.33
Detectable pericarditis occurs in 25% of acute myocardial infarctions and can be recognized by friction rubs and typical symptoms. Lytic therapy reduces the frequency of infarct pericarditis by 50%.34 Atypical T-wave evolution is more sensitive to regional infarct pericarditis than a friction rub. T waves may remain persistently positive for 48 hours or longer (type I), or inverted T waves may gradually become positive (type II). Thus, an accurate patient history, bedside physical examination, and newly reported ECG signs can be used to diagnose a potentially severe complication of acute myocardial infarction.
Chest Roentgenogram
The chest roentgenogram continues to play
a significant role in
the multicenter trials.35 Chest roentgenographic evidence
of interstitial edema and other signs of pulmonary congestion is
closely followed. The cardiothoracic ratio reflects the effect of
treatment.36 Pulmonary congestion and preserved left
ventricular systolic function appear to reflect, to some degree, left
ventricular diastolic function, which plays an important role in the
development of flash pulmonary edema in patients with ischemic heart
disease.37 In patients with acute myocardial infarction,
severe pulmonary congestion is a marker of mortality
effect.38
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Recommendations |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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Recently, a national task force stressed the need for more physicians trained in clinical and preventive medicine.39 This need will be served most efficiently by better bedside training at all levels: among medical students, residents, fellows, and nurses.
The In-Training Examination, the National Board, and specialty examinations should include principles of daily practice, such as physical examination and bedside skills. However, structured bedside teaching must be reviewed before implementing such broad educational objectives.
Restoration of bedside cardiology to its time-honored status may be tedious and difficult. National surveys have revealed the magnitude of the problem. Lectures, visual aids, and other teaching techniques are no substitute for hands-on bedside techniques. We must be ready to face this challenge; economic realities should hasten its success.
Received October 26, 1994; accepted November 24, 1994.
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References |
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TopIntroductionMagnitude of the Problem...Bedside Rounds: Science and...Palpation and Auscultation Do Doppler Ultrasonography and...Supportive Role of Inexpensive...Recommendations References |
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