Search PubMed⌕ Search

Biomedical subjects

M A Mansell

Publications and source records attributed to M A Mansell.

At least 37 records · Page 2Linked to original sources
PubMed1989

The effects of low dose intravenous 99-126 atrial natriuretic factor infusion in patients with chronic renal failure.

The aim was to study the renal and hormonal effects of intravenous 99-126 atrial natriuretic factor (ANF) infusion in a mixed group of patients who had moderate to severe chronic renal failure (CRF) and who were not treated with dialysis. The peak mean plasma level of ANF achieved during the experiment was at the upper limit of an absolute range of basal values previously recorded in a larger group of patients with similar degrees of renal impairment. A significant tissue effect was confirmed by rises in plasma and urinary cyclic guanosine monophosphate, the 'second-messenger' of ANF. ANF infusion increased sodium excretion rate by a mean of 68% compared with a fall of 40% in a placebo group, and significant increases in urinary albumin excretion occurred during the peptide infusion. Thus, the high levels of plasma ANF found in CRF may have a role in the maintenance of sodium balance. In addition, the proteinuric effect may be detrimental to long-term renal function.

Atrial Natriuretic Factor↗
PubMed1989

Treatment of resistant CAPD peritonitis by temporary discontinuation of peritoneal dialysis.

Resistant continuous ambulatory peritoneal dialysis (CAPD) peritonitis (recurrent or persistent infection) is traditionally treated by removal of the CAPD catheter and a period off peritoneal dialysis. In a pilot study we have treated 8 patients with recurrent staphylococcal peritonitis and 3 patients with persistent staphylococcal peritonitis by stopping CAPD for a 2-week period, the CAPD catheter being left in-situ. All 8 patients with recurrent peritonitis and 2 of the 3 patients with persistent peritonitis had resolution of their infection; the third patient required catheter removal to clear the infection. There were no acute problems associated with stopping CAPD, and there was no evidence of loss of peritoneal filtration capacity on restarting CAPD. This novel approach to the treatment of resistant CAPD peritonitis should reduce the number of CAPD catheters replaced and therefore diminish the risks and inconvenience to patients that such replacements entail.

Catheters, Indwelling↗
PubMed1988

Changes in blood acetaldehyde concentrations during acetate haemodialysis.

Hyperacetataemia during acetate haemodialysis has been associated with the development of a variety of unpleasant symptoms, although a direct toxic effect of acetate is hard to prove. Acetaldehyde, which is produced during the metabolism of ethanol to acetate, has various toxic effects including some of those reported during acetate dialysis such as nausea, headache and palpitations. Using a novel, recently developed method we studied blood acetaldehyde concentrations during acetate dialysis in 15 patients and found significant increases in five, with a mean peak value in these patients of 1.36 mumol/l (normal less than 0.4 mumol/l). These five patients also developed high blood acetate concentrations during a subsequent acetate dialysis and showed a significant correlation between blood acetaldehyde and acetate concentrations (r = 0.55, P less than 0.05). Blood acetaldehyde did not change during bicarbonate dialysis in these patients. Our results suggest that significant accumulation of acetaldehyde may occur during acetate dialysis, especially in those patients whose metabolic capacity for acetate is somehow impaired, and that acetaldehyde may contribute to some of the symptoms previously ascribed to 'acetate' intolerance.

Acetaldehyde↗
PubMed1988

The effect of induced hypotension and tissue trauma on renal function in scoliosis surgery.

The surgical correction of scoliosis in adolescents involves considerable trauma to bone and muscle which, together with hypotensive anaesthesia, might be expected to compromise renal function. Our recent observation of acute renal failure in two such patients prompted a prospective study of renal function following 52 operations in 43 patients. Despite hypotension, blood loss, muscle damage and evidence of fat embolism, renal function was unaltered in all patients, and there was no impairment of spinal cord function. Careful attention was paid to the maintenance of circulating volume which is essential to protect renal perfusion.

Adolescent↗
PubMed1988

The effect of renal transplantation on plasma atrial natriuretic peptide.

The changes in plasma atrial natriuretic peptide (ANP) were studied in four adult patients after cadaveric renal transplantation. In three patients who achieved good renal function, the correction of volume overload, as reflected by reduction in weight and right atrial pressure, was associated with a steady fall in plasma ANP and a parallel decrease in both fractional excretion of sodium and plasma cyclic guanosine monophosphate. The fourth patient, with severe acute rejection, developed severe peripheral oedema, and fractional sodium excretion remained low despite high values of ANP.

Adult↗
PubMed1987

Renal abnormalities in ankylosing spondylitis.

The incidence of renal abnormalities is increased in patients with ankylosing spondylitis (AS). Possible mechanisms include the effects of nonsteroidal anti-inflammatory drugs (NSAIDs), an increased incidence of glomerulonephritis and the deposition of amyloid. We assessed renal function in 51 patients with AS randomly selected from those attending routine rheumatology clinics. Five patients were found to have a definite renal abnormality and three of them underwent renal biopsy. These showed one case each of IgA glomerulonephritis, focal segmental glomerulosclerosis and nonspecific tubulo-interstitial damage. A sixth patient had recurrent haematuria and borderline renal functional impairment but refused further investigation. The urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG) was elevated in four patients; two had other biochemical evidence of renal damage while the other two patients appeared normal, although they had both received spinal irradiation in the past. The finding of a significant renal abnormality in 10% of AS patients suggests that evidence of renal involvement should be actively sought in this disease.

Adult↗
PubMed1987

Oxalate dynamics in chronic renal failure. Comparison with normal subjects and patients with primary hyperoxaluria.

In order to separate the effect of oxalate retention in primary hyperoxaluria with renal failure from that of excessive oxalate synthesis and to determine the optimum time for renal transplantation in primary hyperoxaluria, we have studied a series of patients with different degrees of renal failure due to other causes. The results were compared with those obtained in studies on 8 patients with primary hyperoxaluria at different levels of residual overall renal function. In the patients with renal failure unrelated to primary hyperoxaluria, oxalate retention increases rapidly when the glomerular filtration rate (GFR) decreases below about 20 ml X min-1. These results suggest that the reduced renal excretory contribution to oxalate accumulation in primary hyperoxaluria would be expected to be particularly important in this range of GFR. In primary hyperoxaluria, oxalate retention occurs when GFR is only a little below the reference range and measures to remove oxalate from the body should be considered when the GFR falls below 40 ml X min-1 X 1.73 m-2, with a view to their introduction when the GFR is in the range 20-25 ml X min-1 X 1.73 m-2.

Carbon Radioisotopes↗
PubMed1987

Red-cell calcium in patients with renal failure.

The red-cell calcium concentration, measured by atomic absorption spectrophotometry, was found to be significantly higher in patients with end-stage renal failure than in healthy volunteers. This provides one possible explanation for some of the abnormalities of red-cell metabolism known to occur in uraemia.

Calcium↗
PubMed1987

Cardiovascular and acid-base effects of acetate and bicarbonate haemodialysis.

Cardiovascular and acid-base changes were studied in 18 adult haemodialysis patients during a single dialysis against acetate or bicarbonate dialysate. Tachycardia was significantly greater with acetate but, otherwise, blood pressure and peripheral resistance fell and cardiac output increased to a similar degree with the two types of dialysate. Arterial PCO2 increased with bicarbonate and fell slightly with acetate, while hypoxaemia was significantly worse during acetate dialysis. Arterial acetate concentrations increased in 2 of 12 patients during bicarbonate dialysis. No differences in patient symptomatology or hypotensive episodes were noted with acetate or bicarbonate. Any beneficial effects of bicarbonate dialysis are more likely to be related to preservation of arterial PO2 than to the absence of adverse cardiovascular effects of acetate.

Acetates↗