Favorable outcome of neonatal aortic thrombosis and renovascular hypertension

Fifteen children with renovascular hypertension as a result of aortic thrombosis were followed for a mean of 26 months (range 5 to 58 months) to determine outcome. As neonates, all patients had hypertension and elevated plasma renin activity. Of 11 patients studied with radionuclide renography and scintigraphy, 10 had abnormal renal blood flow; three had complete absence of unilateral perfusion. On follow-up examination all children were normotensive; five children ages 5 to 24 months required antihypertensive medication. Of 15 children, 14 had normal statural growth; all had normal serum creatinine, plasma renin activity, and calculated glomerular filtration rate values. Patients with complete absence of renal perfusion unilaterally remained functionally anephric; children with less severe perfusion deficits had improved perfusion as shown by radionuclide renography and scintigraphy. We believe that many patients with aortic thrombosis and renovascular hypertension who have had aggressive antihypertensive therapy in the neonatal period will have good renal function and increased perfusion to the affected kidney 2 years later.     

Calciphylaxis – a topical overview

'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.     

The perils of power in interpretive research.

Occupational therapy is based on core values of altruism, equality, and honoring the dignity of others. Embedded in these values is the ever-present negotiation of power. To honor the concern for the welfare of others, researchers are challenged to think about issues of power throughout the research process. This paper identifies dilemmas and raises questions researchers might ask themselves as they struggle to share power in the interpretive research process.     

Fieldwork supervision: more education is warranted

Students completing fieldwork are the future of our profession. We can no longer allow our fieldwork educators to develop skills to supervise, teach, and evaluate students on a trial-and-error basis. By allocating resources to develop continuing education materials to be used in developing these skills, the profession will be acknowledging its long-standing espoused commitment to fieldwork. The development of continuing education materials must be based on an understanding of how experienced clinicians reason about their practice and transform occupational therapy theory into clinical practice. Critical analysis of the reasoning process will help us teach this process to students. Additionally, we need to develop self-contained educational materials to prepare our fieldwork educators to design fieldwork programs, supervise students, and handle administrative issues related to fieldwork. Finally, fieldwork educators and academic faculty need to collaborate to provide our future practitioners with an integrated academic and clinical education.     

Controlled reperfusion of the regionally ischemic myocardium with leukocyte-depleted blood reduces stunning, the no-reflow phenomenon, and infarct size.

Open-chest sheep underwent 90 minutes' occlusion of the diagonal branch of the left anterior descending coronary artery, followed by vented cardiopulmonary bypass. After 30 minutes of cardioplegic arrest, simulating distal anastomoses, the occlusion on the coronary artery branch was released. Controlled reperfusion (40 to 50 mm Hg, 135 to 150 ml/min) for the first 20 minutes was delivered at the aortic root with either unmodified whole blood (control, n = 7) or blood passed through leukocyte filters (filters, n = 7). Serial measurements were made during 3 additional hours reperfusion off cardiopulmonary bypass. During ischemia, the major determinants of infarct size, which include area at risk, collateral myocardial blood flow, and rate-pressure product were not significantly different between groups. Overall, during reperfusion, mean left ventricular stroke work index in the filter group was greater than in the control group (28.7 +/- 5.8 versus 12.6 +/- 6.4 x 10(3) erg/gm, p less than 0.05), as was mean rate of rise of left ventricular pressure (1900 +/- 260 versus 1348 +/- 279 mm Hg/sec, p less than 0.05). Myocardial blood flow to the area at risk at 3 1/2 hours of reperfusion in the filter group was also significantly better than in the control group (0.57 +/- 0.15 versus 0.27 +/- 0.05 ml/min/gm, p less than 0.05), as was necrotic area as a percentage of area at risk (40% +/- 6% versus 70% +/- 5%, p less than 0.05). These results demonstrate amelioration of myocardial stunning and the no-reflow phenomenon, as well as decreased infarct size. We conclude that controlled reperfusion with leukocyte-depleted blood is superior to whole-blood reperfusion for the surgical treatment of acute regional ischemia.