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P Zucchelli

Publications and source records attributed to P Zucchelli.

At least 55 records · Page 3Linked to original sources
PubMed1995

Effects of automatic blood volume control over intradialytic hemodynamic stability.

Due to the crucial role of hypovolemia in the genesis of dialysis-induced hypotension, we have evaluated whether the automatic control of the intradialytic blood volume (BV) decrease along a preset trajectory might be beneficial to the hemodynamic stability during treatment. Five frequently hypotensive HD patients were studied and a 3-period-protocol (A1-B-A2) was adopted, each period lasting 6 sessions per patient. During the B periods the patient BV decrease was kept along a predefined profile, thanks to an automatic system with a retroactive control of both the ultrafiltration rate (UFR) and dialysate conductivity (DC); instead, during the A periods, conventional HD was performed, with linear UFR and constant DC, inducing a spontaneous decrease in BV. The intradialytic BV behaviour was much more stable during the B-periods (-10.2 +/- 1.4% by the end of the treatment) than during the A1 (-11.2 +/- 3%) and A2 periods (-11.5 +/- 2.5%). Only one dialysis-hypotension episode was observed during the B periods, compared to 8 and 5 during the A1 and A2 periods, respectively (p < 0.05). The automatic control of the BV changes during dialysis could improve the intra-treatment cardiovascular stability in critically-ill patients.

Biofeedback, Psychology↗
PubMed1994

Renal artery angioplasty for renovascular hypertension and preservation of renal function: long-term angiographic and clinical follow-up.

OBJECTIVE: Percutaneous transluminal angioplasty of stenoses of the renal artery can be used to treat hypertension and renal insufficiency. Although many studies have been published on the short-term results of this procedure, few long-term studies are available. SUBJECTS AND METHODS: One hundred ninety-five patients (123 men and 72 women 19-79 years old; mean age, 56 years) with stenosis of the renal artery and hypertension underwent renal percutaneous transluminal angioplasty at our institution. The stenosis was unilateral in 66% of patients, bilateral in 26%, and in a solitary functioning kidney in 8%. Renal insufficiency was present in 31% of patients. After renal percutaneous transluminal angioplasty, long-term clinical and angiographic follow-up was evaluated by life-table analysis. RESULTS: In patients with fibromuscular disease, blood pressure returned to normal in 57%, improved in 21%, and was unchanged in 21%. In patients with atherosclerotic stenosis, blood pressure returned to normal in 12%, improved in 51%, and was unchanged in 37%. After percutaneous transluminal angioplasty, renal function improved in 48% of patients with renal insufficiency due to bilateral stenosis or stenosis in the single functioning kidney, whereas none of the patients with unilateral stenosis of renal artery and renal insufficiency had any notable improvement. Long-term follow-up showed a high rate (82%) of patency of revascularized arteries and a low rate (21%) of hypertension recurrence at 5 years. CONCLUSION: Renal percutaneous transluminal angioplasty is useful for treating hypertension and for reestablishing renal function. Its effects on blood pressure and renal function are long-lasting in the large majority of patients.

Angioplasty, Balloon↗
PubMed1994

ACE inhibition reduces proteinuria in normotensive patients with IgA nephropathy: a multicentre, randomized, placebo-controlled study.

A multicentre, randomized, placebo-controlled study was performed in 39 adult patients with biopsy-proven IgA nephropathy with the aim of comparing the effects of the ACE inhibitor fosinopril and placebo on proteinuria. All patients had normal blood pressure and normal renal function. Proteinuria ranged from 1.0 to 2.5 g/24 h. After a 3-month run-in period, fosinopril and placebo were randomly administered in two 4-month sequences separated from cross-over treatment by a 1-month interval. The mean values of creatinine clearance did not change during either the placebo or the treatment sequences. The mean values of mean arterial pressure (MAP) were significantly lower during the fosinopril sequence (90.4 +/- 9.0 mmHg) than in basal conditions (92.8 +/- 9.1 mmHg) (P = 0.034). The mean basal values of proteinuria were 1.74 +/- 0.84 g/24 h. They were unchanged during the placebo sequence (1.79 +/- 1.20) and fell to 1.37 +/- 0.98 g/24 h after 4 months of fosinopril treatment. Using a multivariate statistical analysis, the treatment effect by time on proteinuria was significantly evident only in the fosinopril sequence (Wilks test, P = 0.033). Changes in protein excretion were not correlated with changes in MAP, baseline plasma renin activity, and urinary sodium excretion. This controlled study shows that fosinopril can significantly reduce proteinuria even in normotensive patients with IgA nephropathy. Obviously, the results of treatment with ACE inhibitors on long-term renal prognosis remain to be elucidated.

Adolescent↗
PubMed1994

Regulation of base balance in bicarbonate hemofiltration.

The purpose of this study was to investigate the feasibility of bicarbonate as a substitute for acetate or lactate in hemofiltration solutions using a new bag for the bicarbonate substitution fluid. We analysed 24 hemofiltration sessions with different HCO3- concentrations (30, 35 and 40 mEq/L) in the substitution fluid. The increase in the HCO3- concentration in the substitution fluid resulted in a more positive HCO3- balance. The Net Base Gains (NBG) were, respectively, 73.7 +/- 92 with 30, 138.2 +/- 97 with 35 (p < 0.05 vs 30) and finally 201 +/- 65.9 with 40 mEq/L (p < 0.001 vs 30). The physical separation between the base losses and gains could facilitate the modelling approach in hemofiltration. By means of a stepwise regression analysis, we studied a series of variables that could influence end-treatment HCO3-, which was significantly and directly dependent (F = 6.003, r = 0.747, p = 0.0027) on the HCO3- concentration in the substitution fluid and the apparent HCO3- space. HCO3- values predicted by the statistical model correlated well with those actually measured (r = 0.757; p < 0.001). This mathematical modelling approach allowed us to predict the quantities and concentrations of HCO3- to be infused in order to obtain an ideal acidosis correction, tailored to individual patient needs.

Acid-Base Equilibrium↗
PubMed1993

The diagnostic dilemma of hypertensive nephrosclerosis: the nephrologist's view.

The appearance of progressive renal disease in elderly patients with essential hypertension, sometimes irrespective of blood pressure control, is frequently related to the association of hypertension and atheromatous renal disease. This disease may lead to renal failure through a renal artery stenosis and/or chronic microembolization into the kidney. Nonsevere uncomplicated essential hypertension is constantly associated with renal vascular changes that are qualitatively indistinguishable from those related to aging. Notwithstanding the fairly constant presence of so-called benign hypertensive nephrosclerosis in patients with established hypertension, only a subset of these patients show progressive renal damage. Three mechanisms of progression may be at play: (1) a combination of ischemic and hypertensive glomerular mechanisms in some susceptible humans; (2) nonhemodynamic factors such as local immune mechanisms; or (3) the involvement of metabolic abnormalities which favor glomerulosclerosis.

Aged↗
PubMed1993

Continuous on-line optical absorbance recording of blood volume changes during hemodialysis.

Conventional techniques that measure blood volume changes during hemodialysis are invasive, hard to reproduce, and provide only intermittent evaluations. To overcome these drawbacks, we have developed an optoelectronic instrument that estimates intradialytic blood volume percentage changes by the optical absorbance of blood. This device is based on the absorption of light transmitted through blood, which is directly related to the hemoglobin concentration. A personal computer interfaced to the device provides a continuous on-line graphic display of the hemoglobin levels and the percentage changes in blood volume. The noninvasive measurement of dialysis blood volume changes by an optical method may be helpful in detecting the appearance of severe hypovolemia that can be dangerous in critically ill patients.

Absorption↗
PubMed1993

Relationship between plasma beta 2-microglobulin and residual diuresis in continuous ambulatory peritoneal dialysis and hemodialysis patients.

To evaluate whether the continuous ambulatory peritoneal dialysis (CAPD) technique is able per se to obtain lower beta 2-microglobulin (beta 2M) plasma levels than hemodialysis (HD) or whether other factors, such as residual diuresis, can make a significant contribution, we compared 69 CAPD and 38 cuprophan HD patients, matched for age and dialysis duration. Residual diuresis was 680.3 +/- 531.8 mL/day in CAPD and 285.5 +/- 381.8 mL/day in HD (p < 0.001) subjects. Daily diuresis was > 300 mL/day in 63.8% of CAPD and in 31.6% of HD patients. The beta 2M plasma levels were 26.3 +/- 9.9 mg/L and 34.9 +/- 13.3 mg/L (p < 0.001) in CAPD and HD, respectively. In both groups the difference was significant when we compared the patients with diuresis below versus above 300 mL/day (p < 0.001). Instead, the differences were not significant upon comparing the CAPD and HD patients with the same amount of daily diuresis. The comparison between beta 2M plasma levels and residual diuresis showed a significant inverse correlation in both groups (p < 0.001). We conclude that the dialysis technique itself does not affect beta 2M plasma levels. The diuresis volume may be a very important factor in lowering beta 2M levels in both CAPD and HD patients. CAPD's capacity to maintain a higher diuresis for longer than HD may account for the lower beta 2M plasma levels in CAPD patients.

Aged↗
PubMed1993

Lupus membranous nephropathy: long-term outcome.

The follow-up of 42 patients affected by lupus membranous nephropathy (LMN) is reported and compared with that of 43 patients affected by diffuse proliferative lupus glomerulonephritis (DPGN), who were the object of a previous study. According to the WHO classification, the patients were subdivided into two groups: pure LMN (Va + Vb class) and LMN with superimposed proliferative lesions (Vc + Vd class). Antiphospholipid antibodies (APA) and lupus anticoagulant were tested in 23 subjects. All the patients were treated with corticosteroids, which were associated to cytotoxic drugs in 28 cases. Although a higher number of complete remissions was obtained in patients with pure LMN, the difference between the 2 groups was not significant (7/26 vs 1/16). At 10 years kidney survival was 93% in all LMN patients with no significant differences between the 2 groups. This 10-year kidney survival rate is very similar to that previously observed by us for DPGN (91%). The WHO histological classification and the chronicity index did not identify the patients who reach end-stage renal failure. Eight patients suffered from thrombotic manifestations which were the cause of death in two cases. Fourteen of the 20 patients studied presented echocardiographic abnormalities. A statistically significant association was found between the occurrence of cardiovascular complications and APA levels. The effectiveness of treatment in LMN remains controversial. We suggest, however, that adequate therapy may significantly improve the prognosis of lupus nephritis thus reducing the differences in the outcome of SLE patients having different histological WHO classes. Cardiovascular illness represents a frequent and severe late complication.

Adult↗