Efforts to curtail abuse of alcohol and other drugs concentrate on activities designed for supply-and-demand reduction. Many law enforcement and health officials agree that the reduction in supply of drugs cannot succeed as long as the demand for drugs for purposes of abuse occurs in a significant segment of society. Critical to reducing this demand is prevention. Only through an understanding of the correlates and risk factors associated with the use of alcohol and other drugs, along with the identification and implementation of sound strategies, can change occur. Although research has uncovered a considerable body of knowledge about the interplay of personal behavior, risk factors, and health in the prevention of substance abuse, many questions remain unanswered. Until those answers are known, efforts that have proven most effective need to be more widely emphasized.

Is a permanent injury more likely to elicit a rating of inappropriate care than a temporary injury? To explore this question, we asked 112 practicing anesthesiologists to judge the appropriateness of care in 21 cases involving adverse anesthetic outcomes. The original outcome in each case was classified as either temporary or permanent. The authors then generated a matching alternate case identical to the original in every respect except that a plausible outcome of opposite severity was substituted. The original and alternate cases were randomly divided into two sets and assigned to reviewers who were blind to the intent of the study. The reviewers were asked to rate independently the care in each case as appropriate, less than appropriate, or impossible to judge, based on their personal (implicit) judgment of reasonable and prudent practice. A significant inverse relationship between severity of outcome and judgments of appropriateness of care was observed in 15 (71%) of the 21 matched pairs of cases. Overall, the proportion of ratings for appropriate care decreased by 31 percentage points when the outcome was changed from temporary to permanent and increased by 28 percentage points when the outcome was changed from permanent to temporary. We conclude that knowledge of the severity of outcome can influence a reviewer's judgment of the appropriateness of care.

To quantify the effect of estrogen replacement therapy on breast cancer risk, we combined dose-response slopes of the relative risk of breast cancer against the duration of estrogen use across 16 studies. Using this summary dose-response slope, we calculated the proportional increase in risk of breast cancer for each year of estrogen use. For women who experienced any type of menopause, risk did not appear to increase until after at least 5 years of estrogen use. After 15 years of estrogen use, we found a 30% increase in the risk of breast cancer (relative risk, 1.3; 95% confidence interval [CI], 1.2 to 1.6). The increase in risk was largely due to results of studies that included premenopausal women or women using estradiol (with or without progestin), studies for which the estimated relative risk was 2.2 (CI, 1.4 to 3.4) after 15 years. Among women with a family history of breast cancer, those who had ever used estrogen replacement had a significantly higher risk (3.4; CI, 2.0 to 6.0) than those who had not (1.5; CI, 1.2 to 1.7).

Cardiopulmonary resuscitation (CPR) is routinely performed on hospitalized patients who suffer cardiac or respiratory arrest. Consent to administer CPR is presumed since the patient is incapable at the moment of arrest of communicating his or her treatment preference, and failure to act immediately is certain to result in the patient's death. Two exceptions to the presumption favoring CPR have been recognized, however. First, a patient may express in advance his or her preference that CPR be withheld. If the patient is incapable of expressing a preference, the decision to forgo resuscitation may be made by the patient's family or other surrogate decision maker. Second, CPR may be withheld if, in the judgment of the treating physician, an attempt to resuscitate the patient would be futile. In December 1987, the American Medical Association's Council on Ethical and Judicial Affairs issued a series of guidelines to assist hospital medical staffs in formulating appropriate resuscitation policies. The Council's position on the appropriate use of CPR and do-not-resuscitate orders is updated in this report.

We review herein the evidence that estrogen is protective against the development of cardiovascular disease in women. To our knowledge, no studies in women have looked at endogenous estrogen levels as predictors of cardiovascular disease. Studies of surrogate measures of endogenous estrogen such as parity, age at menarche, and age at menopause have provided inconsistent results. Current use of oral contraceptives increases risk in older women who smoke cigarettes, but most studies of past use show no increased risk. Most, but not all, studies of hormone replacement therapy in postmenopausal women show around a 50% reduction in risk of a coronary event in women using unopposed oral estrogen. These important observations need to be confirmed in a double-blind, randomized clinical trial, since the protection is biologically plausible and the magnitude of the benefit would be quite large if selection factors can be excluded.

As new imaging modalities emerge and existing technologies improve, indications for a particular imaging method may change. This article examines current indications for abdominal and prostatic ultrasound examination and, where possible, compares ultrasound with other imaging techniques. This is not an attempt to list all possible ultrasound indications or examinations, but rather an attempt to serve as an aid to informed imaging selection based on current literature and equipment.

The benefits of continuous antihypertensive therapy have been extensively documented. However, lack of compliance with the prescribed regimen, excessive cost, and troublesome adverse effects of some antihypertensive agents led to the consideration of intermittent therapy or even complete discontinuation of therapy as an effective alternative to lifelong medication. Prospective studies dealing with this subject reported inconsistent results. Nevertheless, they allowed us to identify selection criteria of candidates for step-down or discontinuation of antihypertensive therapy. Such candidates include patients with mild essential hypertension who have one or more of the following characteristics: young age, normal body weight, low salt intake, no alcohol consumption, low pretreatment blood pressure, successful therapy with one drug only, and no or only minimal signs of target organ damage. Stopping antihypertensive therapy without subsequent rise in arterial pressure was shown to be possible in a subset of patients with mild essential hypertension for a period of months to years. This approach appears to be safe, provided that blood pressure is monitored frequently, and may improve compliance, save treatment costs, and reduce adverse effects of certain drugs, although its long-term consequences for morbidity and mortality remain to be determined.

To meet the needs of a rapidly growing population and minimize the toxic influences of traditional farming practices on the environment, the American agricultural industry has applied molecular technology to the development of food crops and livestock. By placing genes specific for highly desirable phenotypes into the DNA of plants, animals, and bacteria, farmers have increased crop and livestock survival, enhanced the nutritional quality of foods, increased industry productivity, and reduced the need for toxic pesticides and herbicides. However, introduction of genetically modified foods into the marketplace has raised a spectrum of public health issues. Physicians, as the most proximal scientific resource for most individuals, are uniquely positioned to address patient concerns regarding the safety of genetically altered foods. This report provides an overview of the inherent risks and benefits of "agrogenetics" and offers a series of recommendations designed to promote the education of the medical community and dispel public misconception regarding genetic manipulation.

Over the past 20 years, there has been a dramatic increase in the use of ultrasonography as an imaging modality. The introduction of real-time ultrasonography and Doppler units for the measurement of blood flow in the 1970s, recent advances in transducer design, signal processing, and miniaturization of electronics, along with the lack of radiation exposure, have been primarily responsible for the increased use of ultrasound. However, although ultrasonography can provide diagnostic information safely and easily, interpretation of the information requires an understanding of the physics behind ultrasound, how that physics is translated into ultrasound instrumentation, recognition of artifacts that are associated with the various types of ultrasonography, and identification of these artifacts in specific anatomic locations.

Primary pulmonary hypertension is a clinical syndrome characterized by pulmonary hypertension in the absence of sufficient underlying cardiac, parenchymal pulmonary, or systemic disease to account for it. The population of patients with primary pulmonary hypertension is a heterogeneous one, both clinically and histologically. As the etiologic mechanisms are unknown, therapy is directed toward the consequences of the pulmonary vascular process. Oxygen supplementation, the use of digoxin and diuretics for symptomatic heart failure, and anticoagulation all may have a role in treating primary pulmonary hypertension, although vasodilator therapy has been the main area of investigation. Screening for vasodilator responsiveness, defining a favorable vasodilator effect, predicting long-term effectiveness, and deciding who to treat have all been controversial. New approaches, such as use of high-dose calcium channel-blocking agents and continuous intravenous infusion of prostacyclin (an investigational agent), have recently been proposed. When medical therapies are exhausted, heart-lung or lung transplantation has increasingly become an option for selected patients.

Most cases of typhoid fever in the United States occur in international travelers, with the greatest risk associated with travel to Peru, India, Pakistan, and Chile. Laboratory workers and household contacts of long-term carriers are also at greater risk than the general population. Decisions to the use typhoid vaccine involve weighing the risk of illness against the risk of vaccine reactions. Until recently, the only typhoid vaccine commercially available to US civilians was a heat-phenol-inactivated parenteral product that is 51% to 77% effective in preventing typhoid fever but frequently produces local pain and swelling, fever, headache, and malaise. A new orally administered, live-attenuated vaccine, made from the Ty21a strain of Salmonella typhi, has been recently licensed in the United States. This vaccine provides equivalent protection with a much lower incidence of adverse reactions. It is administered in a four-dose series given over 7 days. Since neither vaccine offers total protection, the most important elements in prevention of typhoid fever remain sound biosafety precautions in laboratory workers and care in selecting food and beverages by those traveling to areas where typhoid fever is endemic.

Most out-of-hospital cardiac arrests result from the sudden onset of a sustained ventricular arrhythmia in the absence of a new myocardial infarction. Individuals who survive cardiac arrest are at high risk for recurrent arrhythmias and sudden unexpected death. To prevent recurrent cardiac arrest, effective treatment must be provided during hospitalization after the initial episode. Caring for the survivor of cardiac arrest requires a detailed clinical investigation to define the underlying cardiac anatomy and left ventricular function and to elucidate the mechanism and characteristics of the patient's arrhythmia. Appropriate antiarrhythmic therapy, such as drugs or a nonpharmacological intervention (eg, implantable cardioverter-defibrillator), is then selected based on these considerations. In addition, ischemia is treated aggressively with beta-adrenergic blocking agents and, when appropriate, with surgical coronary artery revascularization.

Pharmacologic stress imaging has increasingly been employed as an alternative to exercise imaging for detection of coronary artery disease and risk stratification particularly in patients who are unable to perform adequate exercise. Sensitivity and specificity of thallium 201 scintigraphy using intravenous dipyridamole infusion as a stress for coronary artery disease detection average 85% and 91%, respectively. Dipyridamole imaging is also useful for differentiating between ischemia and scar and identifying patients who have an increased risk for subsequent cardiac events. Dipyridamole imaging is particularly useful for preoperative risk stratification in patients undergoing surgery for peripheral vascular or aortic disease. Dipyridamole imaging is also useful for identifying residual myocardial ischemia after myocardial infarction and detecting restenosis after coronary angioplasty. Adverse side effects of dipyridamole are promptly reversed by aminophylline. Dipyridamole stress can also be employed in association with echocardiography for detection of ischemia-induced regional wall motion abnormalities.

Driving and epilepsy is a problem that involves physicians as both care providers to patients and consultants to regulatory authorities. Driving restrictions for people with seizure disorders are intended to ensure the public's safety, but such restrictions may unduly harm the welfare of many people with seizures. In the United States, all states now permit some people with epilepsy to drive. In general, only people whose seizures are adequately controlled are licensed to drive. Adequate control has been judged principally by the seizure-free interval, but individual state standards widely vary. There is a trend toward greater liberalization of driving standards for people with seizure disorders, but the appropriateness and application of these standards continue to raise questions, as does the role physicians should have in the licensing process. Our responsibilities to persons with disabilities and advances in our understanding of seizures and the nature of driving risks warrant a reappraisal of the current medical, legal, and social implications of driving and epilepsy.