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Biomedical subjects

J A Alexander

Publications and source records attributed to J A Alexander.

At least 91 records · Page 5Linked to original sources
PubMed1991

Familial recurring cardiac myxoma.

A 34-year-old woman presented with her fourth occurrence of an atrial myxoma and a right lower lung field mass. Her surgical history was extensive. In addition to resection of three previous atrial myxomas, she had undergone resection of her adrenal glands as a teenager because of Cushing's syndrome, and a hysterectomy at age 26 revealed a myxoid leiomyoma. Family history was remarkable as a maternal uncle and daughter died from embolic complications of left atrial myxomas and her sister previously had a left atrial myxoma resected. The patient underwent uncomplicated removal of the myxoma, and resection of the lung mass revealed a granuloma. A review of typical and atypical aspects of cardiac myxomas is provided including a rare and recently described syndrome of familial cardiac myxoma associated with Cushing's syndrome, spotty skin pigmentation and other myxoid tumors.

Adult↗
PubMed1991

Acute porphyria presenting with hyperamylasemia.

An elevation of serum amylase and lipase has not been reported previously to occur with porphyria. In this report, we describe a patient who presented with the clinical and laboratory picture of pancreatitis: elevated amylase, lipase, amylase-creatinine clearance ratio, and with abdominal pain. Only after extensive evaluation, was the patient found to have porphyria. On two separate occasions, with hematin therapy, her serum amylase decreased, as did her clinical symptoms of porphyria and her urinary quantitative porphyrins. This suggests an association between elevation of the serum amylase and lipase with acute porphyria. Moreover, this association can lead to delay in establishing the diagnosis of acute porphyria.

Acute Disease↗
PubMed1991

Radiation-associated valvular disease.

The prevalence of radiation-associated cardiac disease is increasing due to prolonged survival following mediastinal irradiation. Side effects of radiation include pericarditis, accelerated coronary artery disease, myocardial fibrosis and valvular injury. We evaluated the cases of three young patients with evidence of significant valvular disease following mediastinal irradiation. One patient underwent the first reported successful aortic and mitral valve replacement for radiation-associated valvular disease (RAVD) as well as concurrent coronary artery revascularization. A review of the literature revealed 35 reported cases of RAVD, with only one successful case of valve replacement that was limited to the aortic valve. Asymptomatic RAVD is diagnosed 11.5 years after mediastinal irradiation compared with 16.5 years for symptomatic patients, emphasizing that long-term follow-up is important for patients receiving mediastinal irradiation. This study defines a continuum of valvular disease following radiation that begins with mild asymptomatic valvular thickening and progresses to severe valvular fibrosis with hemodynamic compromise requiring surgical intervention.

Adolescent↗
PubMed1991

Adaptive change in corporate control practices.

Multidivisional organizations are not concerned with what structure to adopt but with how they should exercise control within the divisional form to achieve economic efficiencies. Using an information-processing framework, I examined control arrangements between the headquarters and operating divisions of such organizations and how managers adapted control practices to accommodate increasing environmental uncertainty. Also considered were the moderating effects of contextual attributes on such adaptive behavior. Analyses of panel data from 97 multihospital systems suggested that organizations generally practice selective decentralization under conditions of increasing uncertainty but that organizational age, dispersion, and initial control arrangements significantly moderate the direction and magnitude of such changes.

Decision Making, Organizational↗
PubMed1991

The Blalock-Taussig shunt in the newborn infant.

Children with pulmonary oligemia often require palliation in the newborn period. The Blalock-Taussig shunt has been shown to offer adequate palliation in the older child, but its use in the newborn period remains controversial. A retrospective review of 51 neonates younger than age 2 weeks undergoing a Blalock-Taussig shunt (or modification) was performed. The operative mortality rate was 5.8%. Six children (15.4%) required reoperation in the first year of life for inadequate shunt function. The modification with interposition grafts necessitated reoperation more often than shunts performed with the subclavian artery.

Anastomosis, Surgical↗
PubMed1991

Magnetic resonance findings in a patient with internuclear ophthalmoplegia. Neuroradiological-clinical correlation.

A 49-year-old female presented with symptoms compatible with internuclear ophthalmoplegia. Magnetic resonance using T2-weighted images showed an eccentric area of high signal intensity in the mid pons corresponding to the right medial longitudinal fasciculus. Magnetic resonance is the method of choice when internuclear ophthalmoplegia is suspected. The findings should be differentiated from the normal central hyperintensity called the "pseudo MLF hyperintensity."

Female↗
PubMed1990

Gastrointestinal tract hemorrhage. The value of a nasogastric aspirate.

A bloody nasogastric aspirate is believed to imply active upper gastrointestinal tract bleeding, while a nonbloody yellow-green nasogastric aspirate that contains duodenal secretions suggests the absence of bleeding proximal to the ligament of Treitz. To validate these beliefs, physicians were asked to predict the presence of active gastrointestinal tract bleeding and whether bile was present in a nasogastric aspirate obtained immediately before endoscopy in 73 episodes of bleeding in 62 patients. A relationship was found between the physician's assessment of the presence of active bleeding demonstrated endoscopically and the appearance of the nasogastric aspirate. However, the sensitivity and specificity were low (79% and 55%, respectively). No association between the assessment of bile in the nasogastric aspirate and the presence of bile acids was demonstrated. These data do not support the placement of a nasogastric tube to determine whether or not a patient is bleeding, the location of the bleeding, and whether endoscopy should be performed.

Bile↗
PubMed1990

Serum-ascites albumin gradients in nonalcoholic liver disease.

Several studies performed in alcoholics with advanced liver disease have demonstrated a positive correlation between the serum-ascites albumin gradient (SAAG) and measured portal venous pressure. A single study performed in 15 patients with exudative malignant ascites and 29 patients with alcoholic liver disease demonstrated that a SAAG of less than 1.1 was essentially diagnostic of a malignant origin of the ascites. In an effort to confirm and extend these observations to individuals with nonalcoholic liver disease, 24 patients with nonalcoholic liver disease and 11 with alcoholic liver disease undergoing orthotopic liver transplantation (OTLx) were studied. At the time of liver transplantation, each had their serum and ascitic fluid albumin levels determined, the gradient calculated, and their portal venous pressure (PVP) as well as the corrected portal venous pressure (PPc) measured directly. A significant correlation (r = 0.624) between the PPc and the SAAG was found in the 11 alcoholics (P less than 0.05). No such correlation existed for those with nonalcoholic liver disease (r = 0.398). Moreover, a SAAG less than 1.1 was found in three of nonalcoholics with cirrhosis in the absence of an abdominal malignancy. We conclude that (1) the SAAG and PPc are statistically related to each other in individuals with alcoholic liver disease but not in those with a nonalcoholic cause for cirrhosis, and (2) SAAG less than 1.1 is not diagnostic of abdominal malignancy but can occur in those with advanced nonmalignant hepatic disease.

Adult↗
PubMed1990

Feasibility of reversible pulmonary artery banding: early results and intermediate-term follow-up.

Development of a reversible pulmonary artery band might obviate the need for a second cardiac surgical procedure in children with some forms of congenital heart disease. We evaluated a segmented Silastic-coated Dacron mesh band 2 to 4 mm wide sewn together with absorbable 2-0 polydioxanone suture for use as a reversible pulmonary artery band. Nine puppies 6 to 8 weeks old (mean weight, 5.8 kg) underwent placement of this pulmonary artery band. All survived the operation with a mean initial systolic gradient of 6.5 +/- 1.6 mm Hg and underwent cardiac catheterization at monthly intervals for 3 months. Two puppies died of right ventricular failure. The remaining puppies underwent balloon angioplasty with balloons 20 to 25 mm in diameter. No complications resulted from balloon angioplasty, but 1 puppy died 24 hours later of unidentified causes. Balloon angioplasty decreased the mean gradient from 46.7 +/- 6.8 mm Hg to 6.7 +/- 2.6 mm Hg. Angiography showed an increase in mean diameter of the site of the pulmonary artery band from 5.2 +/- 1.0 to 10.8 +/- 1.7 mm Hg. There was no evidence of vessel injury on angiograms. Fourteen months after balloon angioplasty, the mean gradient was 22.3 +/- 17.0 mm Hg. Our data demonstrate that a functionally reversible pulmonary artery band constructed of segmented Silastic-coated Dacron mesh and 2-0 polydioxanone suture is feasible.

Angioplasty, Balloon↗
PubMed1990

Physician integration strategies and hospital output. A comparison of rural and urban institutions.

Physician integration strategies are attempts to bring physicians into hospital administration by giving them a role on the hospital board, employing them in administrative or clinical capacities, or expanding the administration issues dealt with by medical staff committees. This study used a production function model to examine whether such strategies affect hospital output, measured as case mix-adjusted discharges. The article hypothesizes that less management depth, smaller medical staffs, and an absence of nearby hospitals make physician integration a more important strategy for rural than urban hospitals. American Hospital Association data on 1,309 hospitals from 1982 showed there is no statistically significant evidence that physician integration affects the output of urban hospitals. However, four of the five measures were associated with more patient discharges in rural hospitals. Furthermore, rural and urban hospitals differ in their use of other inputs. It was concluded that physician integration can be an effective mechanism to enhance rural hospital output and that more research on rural hospitals is needed.

Decision Making↗
PubMed1990

Diversification behavior of multihospital systems: patterns of change, 1983-1985.

Studies of diversification in the health care sector have typically focused on hospital-level activity. Little attention has been given to the broader organizational context in which many hospitals operate (multihospital systems, parent holding companies). This article empirically examines diversification behavior of 100 multihospital systems between 1983 and 1985 in order to assess how systems respond to resource constraints, uncertainty, and competitive pressures on inpatient care. Patterns of diversification are identified, and their implications for systems strategic behavior are discussed.

Commerce↗
PubMed1989

Sodium protects against nephrotoxicity in patients receiving amphotericin B.

Neutropenic patients receiving amphotericin B, frequently in combination with aminoglycosides and vancomycin, were prospectively monitored for the development of nephrotoxicity. Based on previous studies, the authors recommended that these patients receive greater than or equal to 90 meq of sodium/day on each day of amphotericin B administration. Patients who received this amount of sodium on every day of amphotericin B therapy were classified as adequate sodium. The adequate sodium group was further subdivided on the basis of whether or not the adequate sodium was in the form of sodium ticarcillin. Patients not receiving this amount of sodium on every day of amphotericin B therapy were classified as inadequate sodium; overall, these patients received greater than or equal to 90 meq of sodium/day on 74% of days on which they received amphotericin B. The inadequate sodium and adequate sodium groups did not differ significantly with respect to age, gender, diagnoses, or baseline creatinine. The incidence of nephrotoxicity (creatinine greater than or equal to 2.0 mg/dl) was significantly higher, 4 of 14 (29%), in the inadequate sodium group, as compared to the adequate sodium, adequate ticarcillin group, 1 of 35 (3%), or the adequate sodium only group, 1 of 24 (4%), p = .008. To adjust for total amphotericin dose, the risk of nephrotoxicity as a function of time on study was evaluated by the life table method; the risk of nephrotoxicity was significantly greater in the inadequate sodium group, p = .019.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1989

Governing boards and profound organizational change in hospitals.

Over the past decade the importance of governing boards as policy-making setting and oversight units within organizations has increased dramatically. Although this is true for both corporate- and private-sector organizations (Bacon and Brown 1977; Gelman 1988), it is particularly relevant to the health sector. Hospital governing boards, long considered inconsequential in hospital management, have recently become subject to closer scrutiny. The role of governing boards in decisions affecting hospital strategy and hospital performance is once again a topic of some interest in boardrooms and hospital trade journals. Impressive evidence of the renewed interest in governance is provided by the funding of an instructional consortium by the S.K. Kellogg Foundation to help strengthen trusteeship and governing board decision making, and to improve education for health services managers in the area of governance. Members of the consortium include the Hospital Research and Educational Trust, the American Hospital Association, the American College of Healthcare Executives, and the Association for University Programs in Health Administration. Among the activities being undertaken by this consortium is the development of a self-assessment tool/methodology for boards, a bibliography and reference guide on effective governance for practicing trustees, research workshops for faculty in health administration programs, and a teaching guide on governance and trustee leadership. Despite this interest, the question with which we began this article persists. Do governing boards make a difference? In the course of our review of previous work on governance we found that, more often than not, that question has been transformed into: how do boards influence hospital performance? And very often that question has been further narrowed into: which board structure leads to better hospital performance? We have argued for a respecification of the initial question. Rather than pursuing a definition of the maximally performing governing board, we should perhaps shift our focus back to a fuller understanding of board structure and function, and its influence on hospital change. The model developed here combines four essential, and very basic, questions: 1. What are the basic dimensions that underlie structural variation in different types of governing boards? 2. How do these board types influence structural change in hospitals? 3. How is the effect of board influence on change itself likely to change over time as a function of the hospital's general pattern of growth, decline, stability, or instability?(ABSTRACT TRUNCATED AT 400 WORDS)

Decision Making, Organizational↗