Biomedical subjects
Publications and source records attributed to J Varon.
Excessive daytime sleepiness has various causes, and appropriate treatment varies accordingly. The diagnosis requires a history, physical examination, and polysomnographic study. A case report exemplifies the clinical approach.
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The posterior approach for correction of the webbed neck defect involves wide anterolateral skin undermining and skin resections from the nape of the neck. The redundant tissue and the underlying defect are corrected and the resultant scar is hidden in the scalp rather than being exposed on the lateral aspect of the neck or shoulder as would be the case with a Z-plasty procedure. In addition, the hairline remains smooth and in a relatively natural position. The surgical dissection is not difficult, and few anatomical structures are involved. The procedure has been employed in 4 patients and has proved to be effective and safe, with long-lasting improvement and acceptable aesthetic results.
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One of the most startling ideas of modern medicine is that "sudden death" may be reversed; however, this idea was not reached easily. In its earliest forms, cardiopulmonary resuscitation (CPR) is probably as old as the human being. The evolution of CPR represents, as does the evolution of medicine as a whole, a history of human error and human discovery. Although it is common to ascribe the development of CPR to Kouwenhoven and colleagues at Johns Hopkins Hospital, in fact they refined and popularized a method that had been evolving over several millennia. This paper reviews the most important advances in resuscitation prior to the 20th century.
The discovery of penicillin was directly linked to the inhibition by that agent of the growth of colonies of staphylococcus. However, subsequent resistance by this organism to penicillin as well as to a number of other agents has marked the history of staphylococcus in the antibiotic era. One of the most important mechanisms of this resistance has been the production of penicillinase, an enzyme that inactivates penicillin and related antibiotics. Penicillinase is currently termed beta-lactamase, and it is now recognized that there are several types of beta-lactamases produced by various organisms. The ability of staphylococci to produce this enzyme has been countered by the development of penicillinase-resistant agents and the addition of beta-lactamase inhibitors to antibiotics.
Austin Flint first ausculted the murmur associated with his name in 1859. Suspecting it to be of mitral origin, he identified it as occurring in aortic insufficiency three years later. Recent echocardiographic study has indicated that this murmur is produced by an aortic insufficiency jet colliding with the anterior mitral valve leaflet. Flint was among the first to recognize the importance of normal cardiac and respiratory sounds. He advocated routine auscultation on all patients, and had great influence in popularizing auscultation in American medicine.
Although the systolic click was first mentioned in the medical literature in 1887, it was not until the investigations of John Barlow and his colleagues in the 1960s that it became linked to the mitral valve and mitral valve prolapse identified as the cause. Mitral valve prolapse is currently the most commonly diagnosed cardiac valvular abnormality. Significant complications may occur with mitral valve prolapse, though most patients are asymptomatic. However, a number of issues persist regarding mitral valve prolapse, especially with respect to the mitral valve prolapse syndrome, a term which has been applied to patients who develop a variety of symptoms, including chest pain, shortness of breath, fatigue, lightheadedness, syncope, palpitations, anxiety, and panic attacks.
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Wilhelm Konrad Roentgen presented a preliminary report on his discovery of x-rays in 1895. In his initial experiments with these rays, he had taken a radiograph of his wife's hand. This picture immediately implied a medical use for the new discovery by demonstrating the bones of the hand. Various aspects of medical treatment were soon revolutionized by the technique of radiography. There were concerns expressed by the medical community regarding the use of x-rays. Many of these concerns regarded deficiencies that were subsequently overcome by technical improvements, resulting in a higher quality of radiographs. However, the benefit of ever-improving radiographic techniques is undergoing greater scrutiny regarding its cost and utility.
Congestive heart failure (CHF) and pulmonary edema are major health problems in the United States as well as across the rest of the developing world. The prevalence of CHF and pulmonary edema in the general population results in a significant number of these patients presenting to Emergency Departments (EDs). Mortality from these disorders is substantial, with a 5-year mortality rate for patients requiring hospitalization of approximately 50%. Understanding of the clinical syndromes of CHF and pulmonary edema requires review of the basic determinants of cardiovascular performance. Preload, afterload, contractility, and heart rate may all be modified by pharmacological or mechanical techniques. Diuretics, vasodilators, cardiac glycosides, and other inotropes all may play a role in the ED management of CHF. In rare instances, mechanical devices for support of the heart and circulation may be indicated.
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The term adult respiratory distress syndrome (ARDS) was first introduced by Ashbaugh and Petty more than two decades ago. Since then, our understanding of this clinicopathologic entity has increased significantly. However, little therapeutic progress has been achieved, and the mortality remains high. ARDS is characterized by diffuse pulmonary microvascular injury resulting in increased permeability and, thus, noncardiogenic pulmonary edema. Ventilation-perfusion lung studies have demonstrated that the predominant pathogenesis of hypoxemia in ARDS is related to intrapulmonary shunts. Common symptoms include dyspnea, tachypnea, dry cough, retrosternal discomfort, and moderate to severe respiratory distress. In most cases the diagnosis of ARDS is that of exclusion. The mainstay of therapy for this syndrome is the management of the underlying disorder causing it. To date, there are no specific pharmacologic interventions of proven value for the treatment of ARDS. Once the potentially treatable sources have been found and their therapy started, the main treatment for ARDS is supportive.
Qualitative and quantitative measurement of the carbon dioxide (CO2) concentration in respiratory gases is readily available with current technology. End-tidal CO2 (PetCO2) monitoring, whether by qualitative colorimetric methods or by solid-state spectrophotometric techniques, is becoming increasingly valuable in the Emergency Department (ED). These techniques offer a practical adjunct to the ED management of critical interventions including endotracheal intubation, conscious sedation, and cardiopulmonary resuscitation.
The clinical features of Guillain-Barré syndrome were initially described by Octave Landry in 1859. Subsequently, Guillain, Barré, and Strohl described a similar syndrome that also displayed a marked increase in cerebrospinal fluid albumin without an increase in white blood cells--an "albuminocytologic dissociation." The hallmark clinical findings in Guillain-Barré syndrome are symmetrical ascending paralysis and areflexia. The differential diagnosis is large, and early cases are often misdiagnosed. Of importance to the emergency physician are the various spinal cord compression syndromes that may present in similar fashion. Acute therapy includes hospitalization and frequent assessment of vital capacity to determine the need for ventilatory assistance.
Continuous cyclical peritoneal dialysis (CCPD) is a well-established, effective method of maintenance dialysis in patients with end-stage renal disease (ESRD). Massive hydrothorax producing hemodynamic compromise (tension hydrothorax) has been documented as an infrequent complication of both acute temporary peritoneal dialysis and continuous ambulatory peritoneal dialysis (CAPD). We recently saw a patient with massive hydrothorax as a consequence of CCPD. The etiology of this rare condition is thought to be that of a diaphragmatic defect with a one-way valve mechanism. Diagnosis is made by aspiration of the pleural fluid and estimation of pleural fluid glucose. Management of these patients requires pleural drainage and changing to hemodialysis if possible.
Moritz Kaposi first published a description of the entity that bears his name in 1872, calling it "idiopathic multiple pigmented sarcoma of the skin." For many years thereafter, Kaposi's sarcoma was considered to be a relatively rare, slow-growing malignancy, most commonly seen in middle-aged and elderly men. This changed in 1981, with Alvin Friedman-Kein's report of what eventually proved to be HIV-associated (epidemic) Kaposi's sarcoma. Kaposi's sarcoma is now one of the diagnostic markers of the acquired immunodeficiency syndrome, as well as the most common neoplastic complication of that disease. HIV-associated Kaposi's sarcoma tends to disseminate widely to mucous membranes and the viscera. Almost all of the cases reported in the United States have occurred in homosexual and bisexual men, and a number of hypotheses have been suggested to explain this association. Over the past several years, however, the incidence of HIV-associated Kaposi's sarcoma has declined, and the reasons for this are also uncertain.
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