In order to establish the normal range of values of Pulsatility (PI) and Resistance (RI) Indices in the intrarenal vasculature, a study of 50 healthy volunteers (23 males, 27 females), divided into five groups of 10 according to age, was performed with Duplex Doppler ultrasound. Both kidneys were examined in all individuals and, in 12, indices were also compared between upper and lower poles of both kidneys. In addition, repeat examinations were performed in nine subjects on three different days, in order to assess the reproducibility of the method. No differences were found in the mean values of both indices between males and females, upper and lower poles, right and left kidneys. A statistically significant increase (p < 0.01, unpaired t-test) was demonstrated when the oldest age group (7th decade) was compared to the youngest age group (3rd decade). The method appeared remarkably reproducible for RI (4.2-7%), with wider variation in the PI (9.5-22.7%).

Adult↗

PubMedDate not supplied

Results from a new renal transplantation unit.

158 kidneys, 9 from living related donors and 149 from cadavers, have been transplanted in the first 42 months of the establishment of a transplant unit at Oxford. Patients' ages ranged from 11 to 56 (mean 35) years. Azathioprine and prednisolone alone were used for immunosuppression, and a minimum-transfusion policy was in operation throughout. After cadaveric transplantation actuarial patient-survival is 70% and 68%, respectively, at the same intervals. 85% of patients who had a functioning graft are fully rehabilitated. Matching for HLA-DR, pregraft blood-transfusions, and the finding that a transplant could be performed in the presence of a positive B-cell crossmatch have proved to be the most significant of the many factors examined both prospectively and retrospectively. The function of the unit is based on dialysis and transplantation for all patients in end-stage renal failure, with transplantation being considered the first line of treatment for patients under the age of 56. The results of transplantation reported here, which have been achieved with conventional immunosuppressive therapy and minimum-transfusion policy, might be considered a standard against which modifications of the practice of renal transplantation can be compared.

Adolescent↗

PubMedDate not supplied

Management of hypertensive crises.

Malignant hypertension still constitutes a medical emergency, particularly when complicated by renal failure, encephalopathy, or left ventricular failure. A shift to the right of the autoregulatory curve of cerebral blood flow (and probably of renal blood flow) is known to occur in patients with hypertension. Local cerebral edema, complicating the malignant phase, is likely to aggravate this trend. While inadequate or tardy treatment leads to encephalopathy, renal and cardiac failure, over aggressive treatment may also result in damage to brain, heart, and kidney. Recent reports of neurological damage, sometimes fatal, following aggressive hypotensive treatment suggests the need for a reappraisal of current practices. More investigation is needed to determine the effects of the various classes of antihypertensive drugs on organ perfusion, particularly of brain, heart, and kidney, in both normal and hypertensive humans. Other hypertensive crises include raised arterial pressure in association with acute dissection of the aorta and in the presence of stroke or subarachnoid hemorrhage. While there is agreement about the need for urgent hypotensive treatment in patients with aortic dissection, there is no information with which to base rational decisions in the management of high arterial pressure in the acute phase of stroke or subarachnoid hemorrhage.

Acute Kidney Injury↗

PubMedDate not supplied

No effect of blood transfusion on muscle metabolism.

31Phosphorus magnetic resonance spectroscopy allows examination of skeletal muscle bioenergetics in vivo. The forearm muscle of four male patients receiving regular blood transfusions for myelodysplastic anaemia showed increased acidification and phosphocreatine depletion during exercise (compared to six age-matched male controls). Transfusion produced no significant improvement in these measurements or in the estimated maximum oxidative capacity of the muscle. We conclude that transfusion of patients with chronic anaemia (haemoglobin of 8-9 g/dl) does not improve skeletal muscle oxidative metabolism.

Aged↗