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R Marcen

Publications and source records attributed to R Marcen.

47 records · Page 3Linked to original sources
PubMed1988

Influence of dialysate and membrane biocompatibility on hemodynamic stability in hemodialysis.

The contributions of membrane biocompatibility, dialysate temperature and sodium concentration to hemodynamic stability during hemodialysis were studied in 8 patients with a high incidence of hemodialysis-induced symptomatic hypotension. Patients were treated during 8 different periods, randomly ordered in each case, resulting from the combination of the following: the membrane, either Cuprophan or Polyacrylonitrile; the dialysate temperature, 37 or 35 degrees C, and the sodium concentration, 133 or 139 mmol/l. The incidence of symptomatic hypotension was lower at 35 degrees C in the entire study with either membrane and either sodium concentration. It was also lower with a sodium concentration of 139 mmol/l with either temperature and either membrane. There was a lower incidence of symptomatic hypotension when using Polyacrylonitrile, but this difference was not significant. We conclude that changes in physicochemical parameters of dialysate lead to worth-while improvement of symptomatic hypotension in hemodialysis patients, but membrane biocompatibility seems to play a minor role.

Aged↗
PubMed1987

Hypertension after renal transplantation. A comparison of cyclosporine and conventional immunosuppression.

Hypertension is a common complication after renal transplantation and is associated with increased mortality. Cyclosporine is known to be nephrotoxic and raises blood pressure in recipients of cardiac and bone marrow transplants, but there is conflicting data on the role of cyclosporine after renal transplantation. We have examined this question in patients entered into the second Oxford prospective randomized comparison of short-term cyclosporine treatment alone with conversion to azathioprine and prednisolone at 90 days (CsA group), and conventional therapy with azathioprine and prednisolone throughout (AP group). Blood pressure and antihypertensive medication were similar in the CsA and AP treatment groups during the first 90 days. Following conversion from cyclosporine, mean blood pressure fell from 155/94 to 142/81 within 7 days, and this fall correlated with the change in plasma creatinine over the same period (r = 0.44, P less than 0.05). Blood pressure was subsequently lower in the converted patients than in those treated with AP throughout. Six months after transplantation patients converted from cyclosporine not only had lower blood pressure but also required fewer antihypertensive drugs than AP patients. This study demonstrates that cyclosporine may elevate the blood pressure in recipients of renal transplants. This effect may either be direct or mediated through the effect of cyclosporine on renal function. Administration of corticosteroids during the first three months after transplantation is implicated as a possible cause of persisting high blood pressure.

Adult↗
PubMed1980

Hypertension following renal transplantation: the role of the host's kidney.

Renin, aldosterone and exchangeable sodium were measured in 38 hypertensive and 56 normotensive renal transplant recipients with good renal function and without renal artery stenosis. Response to competitive blockade of angiotensin II using saralasin was studied in 20 of the hypertensive group. Hypertension was uncommon when bilateral nephrectomy had been performed. When diseased kidneys remained in situ, blood pressure after transplantation correlated well with blood pressure on dialysis. Plasma renin activity was higher in hypertensive patients despite higher exchangeable sodium levels. Urinary aldosterone was also higher and correlated well with blood pressure and plasma renin activity. Angiotensin II blockade produced a fall in blood pressure proportional to plasma renin activity. These observations suggest that hypersecretion of renin is an aetiological factor in the hypertension of renal transplant recipients. It appears to act both through the stimulation of aldosterone secretion, with resultant salt retention, and through the direct vasoconstrictor action of angiotensin II. Since renin levels were lower in patients subjected to bilateral nephrectomy the source of the excess renin is probably the host's kidneys.

Adult↗
PubMedDate not supplied

[Study of renal function after the administration of a low-osmolarity iodized contrast medium. Prospective study].

UNLABELLED: We analysed the development of various kidney function parameters in 40 patients on whom an intravenous urography had been carried out with a non-ionic contrast medium of low osmolarity (iohexol). No patient displayed prior renal insufficiency (serum creatinine 0.4-2mg/dl). Twenty-four hours after injection of the iodized contrast no significant variations in urea blood concentrations, creatinine, sodium or uric acid appeared. As a result of the urography an increase in urine osmolarity and a decrease in fractional sodium excretion took place. IN CONCLUSION: in patients without renal insufficiency intravenous urography with iohexol does not give rise to a significant alteration in the renal excretory function.

Adolescent↗