Biomedical subjects
Publications and source records attributed to J B Nelson.
Arterial aneurysms have been among the relative contraindications cited for extracorporeal shock wave lithotripsy. We report the successful use of extracorporeal shock wave lithotripsy for treatment of renal calculi in a solitary kidney with renal artery aneurysms. Appropriate management considerations and perioperative precautions are discussed.
Two hundred sixty-six of 374 consecutive blunt trauma patients underwent emergency computed tomographic (CT) scanning during evaluation at a level I trauma center. The purpose of this study was to develop guidelines for use of CT scanning in the initial evaluation of blunt trauma patients. Of the 131 CT scans of the head obtained, 20 (15%) had positive results. Seven patients whose initial neurologic examinations were normal had abnormal results on head CT scans; none required emergent treatment of their head injury. This suggests that, in the presence of a normal neurologic examination, head CT scans can safely be delayed until other more serious injuries are addressed. Twenty-six CT scans of the chest were performed and ten (38%) were interpreted as abnormal. Chest CT scans provided information about the extent of the injury but did not alter the initial management of any patient and therefore are rarely indicated in the acute evaluation of trauma patients. A total of 110 abdominopelvic CT scans were performed and 20 (19%) were interpreted as positive. Seventy-five percent of those patients with positive CT scans were treated successfully in a nonsurgical fashion.
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This article begins with a summary of the anatomy and physiology of the upper esophageal region. The appropriate diagnostic tools used in the evaluation of upper esophageal motility disorders are then detailed including cineradiography, manometry, and other modalities. Specific clinical disorders associated with pharyngeal, UES, or upper esophageal dysfunction are described followed by a section on treatment.
Esophageal motility disorders consist of a complex array of disturbances in normal esophageal function associated with dysphagia, gastroesophageal reflux, and noncardiac chest pain. A thorough knowledge of normal esophageal anatomy and physiology is important to a full understanding of these motility derangements. Through a complicated interaction of neuromuscular and hormonal influences, the voluntary act of swallowing transforms into an automated sequence of peristaltic waves propelling food and liquids into the stomach in concert with coordinated relaxation of the sphincters. Anatomic and physiologic barriers exist within the esophagus protecting against gastroesophageal reflux and aspiration. With improvements in diagnostic tools such as barium contrast radiography, scintigraphy, pH measurements, and esophageal manometrics with provocative testing, motility disorders have become better defined and understood. Primary motility disorders consist of achalasia, diffuse esophageal spasm (DES), "nutcracker esophagus," hypertensive lower esophageal sphincter, and nonspecific esophageal motility dysfunction (NEMD). A host of secondary and miscellaneous motility disorders also affect the esophagus, including scleroderma and other connective tissue diseases, diabetes mellitus, Chagas' disease, chronic idiopathic intestinal pseudo-obstruction, and neuromuscular disorders of striated muscle. Gastroesophageal reflux disease (GERD) may also be promoted by associated motility disturbances. Treatment modalities include surgical myotomy; dilatation; and pharmacologic manipulations, including use of nitrates, calcium-channel blockers, H2-blockers, and psychotropic drugs where appropriate.
A retrospective ten-year review of the surgical-intensive-care-unit utilization practices at Riverside Community Hospital revealed that, according to the author's criteria, an average of 32% of over 800 yearly admissions could have been safely managed in a less intensive and expensive environment. The admission practices, monitoring parameters, length of stay, and intensity of nursing interaction were evaluated and compared with those of published reports. Prospective payment by diagnosis-related groups will likely force a change in the existing use of surgical intensive care units. Surgeons are urged to examine the utilization of their hospitals' intensive care units and actively work with their hospital administration to establish intermediate care units so that patients will not be jeopardized by the impending fiscal constraints of diagnosis-related groups.
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One hundred women underwent a 10-week sequential double-blind/crossover to compare conjugated equine oestrogen (Premarin, 0.625 mg and 1.25 mg) with one and two placebo tablets in the management of menopausal symptoms. Sixty-one subjects completed each of in the four regimens. Thirty-one of these continued with their own choice of regimen for a further nine months. Premarin 1.25 mg proved to be significantly more effective (P less than 0.01) in ameliorating menopausal symptoms than Premarin 0.625 mg and both levels of placebo. Premarin 1.25 mg was also preferred as the treatment of choice by the 31 women (P less than 0.001).
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Following voluntary ambulatory turning (eight turns), perceived motion is reversed in direction relative to a) aftereffects of passive rotation and b) predictions from current concepts of immer ear function. Following active turning, feedback from reflexes elicited by vestibulospinal activity apparently dominates the perceptual experience. Practical consequences in medicine and aviation are discussed.
Rabbit hearts were perfused with bicarbonate-buffered fluid containing 1.0 mM glucose and 1.5 mM lactate. Pairs of redox substrates were measured in the perfusion fluid and the heart after perfusate concentrations of beta-hydroxybutyrate (beta-HB) and oxygen were varied. The perfusate lactate to pyruvate ratio was shown to accurately represent the tissue ratio. The intracellular redox state varied independently of changes in substrate uptake. Increasing perfusate beta-HB concentration caused increased beta-HB uptake, decreased lactate uptake, and unchanged glucose uptake. Decreased perfusate oxygen tension caused inhibition of lactate and beta-HB uptakes and, when exteme, caused increased glucose uptake. The combination of a modest reduction in oxygen tension and increased perfusate beta-HB concentration caused a more reduced environment in the tissue than either change by itself. This combination of changes may have additive deleterious effects as suggested by clinical observations.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.