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H Sperschneider

Publications and source records attributed to H Sperschneider.

At least 37 records · Page 2Linked to original sources

Impact of membrane choice and blood flow pattern on coagulation and heparin requirement--potential consequences on lipid concentrations.

BACKGROUND: We reasoned that procoagulant activity, and by implication heparin requirement, during haemodialysis are influenced, amongst other factors, by the type of membranes and the geometry of the blood line system. In addition, there are indications that heparin has dose-dependent effects on the lipid status of chronic haemodialysis patients. METHODS: In a parallel group design we compared patients treated with cuprophane (CU) and polycarbonate-polyether (PC-PE) plate dialysers. In both groups, blood line geometry was varied by including in a first phase and omitting in a second phase drip chambers in the arterial blood line. End-points were changes in coagulation parameters, i.e. thrombin-antithrombin III complex (TAT), plasmin-anti-plasmin complex (PAP), and prothrombin fragment (F1 + 2) concentrations measured by sandwich ELISA. Subsequently all patients were switched to PC-PE dialysers for 6 months and the heparin dose was reduced in a stepwise fashion. Lipid levels and coagulation parameters were monitored. Finally, in an ancillary study, the correlation between heparin dose and LDL/HDL ratio was assessed in patients chronically exposed to PC-PE membranes and low doses of heparin. RESULTS: Post-dialytic concentrations of coagulation and fibrinolysis parameters were significantly lower in the PC-PE group (TAT 31.0 +/- 4.4 micrograms/l; PAP 1180 +/- 148 micrograms/l; F1 + 2 4.2 +/- 0.4 nmol/l) compared to the CU group (TAT 57.3 +/- 10.8 micrograms/l; PAP 1789 +/- 185 micrograms/l; F1 + 2 8.8 +/- 1.0 nmol/l), independently of the use of an arterial drip chamber. Omission of the arterial drip chamber led to lower TAT in the CU group (42.2 +/- 5.8 micrograms/l, P < 0.05), but not in the PC-PE group. In contrast, PAP and F1 + 2 concentrations did not change significantly in either group. Down-titration of heparin dose (from 20.4 +/- 1.1 to 9.4 +/- 0.9 IU/kg/h) was associated with a significant decrease in serum triglycerides (from 2.9 +/- 0.9 to 2.0 +/- 0.6 mmol/l, P < 0.05), LDL-cholesterol (from 3.4 +/- 0.2 to 2.7 +/- 0.4 mmol/l, P < 0.05) and LDL/HDL-ratio (from 3.2 +/- 0.3 to 2.0 +/- 0.3, P < 0.05) with no significant change of total or HDL-cholesterol after 6 months. In an ancilliary analysis, a correlation between lipid parameters (LDL/HDL ratio) and heparin dose was confirmed in 24 patients chronically exposed to PC-PE membranes (r = 0.473, P < 0.05). CONCLUSIONS: In a prospective exploratory study (i) heparin requirement is lower with the use of a polycarbonate-polyether membrane compared to a cuprophane membrane, (ii) heparin requirement is influenced by blood line geometry (decreased with omission of an arterial drip chamber), and (iii) in patients on polycarbonate-polyether membranes down-titration of heparin is associated with a reduction of serum triglycerides, LDL cholesterol, and LDL/HDL ratio. Our data suggest that reduction of heparin dose improves lipid profile. These preliminary observations require confirmation by parallel group controlled studies with controlled dietary intake.

Aged↗

Vitamin C status of patients with chronic renal failure, dialysis patients and patients after renal transplantation.

The vitamin C status of patients with chronic renal failure (CRF), dialysis patients (DP) and patients after renal transplantation (RT) was the object of this investigation. Levels of vitamin C intake from dietary records were estimated at mean values of 93.5 mg/d (CRF), 65.5 mg/d (DP) and 163.9 mg/d (RT). Compared to the recommendation of the German Society of Nutrition (75 mg/d), this indicated a normal range of supply for all groups except the group of DP. The corresponding mean plasma concentrations were 62.2 mumol/l (CRF), 80.3 mumol/l (DP) and 68.8 mumol/l (RT). Supplements of 60 or 100 mg vitamin C given to patients of the DP-group after each dialysis session showed slightly, but not significantly higher concentrations of vitamin C in plasma. During dialysis treatment, plasma vitamin C concentrations dropped to approximately 50% of the basal value, but almost reached initial levels again 44 hours later, both with and without supplementation. During one treatment period, vitamin C loss in the dialysate of three patients ranged between 92.5 and 333.6 mg. The amount of vitamin C in plasma, however, dropped to approximately 50% of the basal value for these patients, too.

Adult↗

Influence of recombinant human erythropoietin therapy on in vivo chemotaxis and in vitro phagocytosis of polymorphonuclear cells of hemodialysis patients.

Recombinant human erythropoietin (rhu-EPO) mainly stimulates erythropoiesis, but also influences the production and function of polymorphonuclear granulocytes (PAN). We evaluated the influence of rhu-EPO therapy in patients on maintenance hemodialysis without iron overload on both phagocytic and chemotactic activity of polymorphonuclear leukocytes (PMN) obtained from blood and a skin chamber. The study comprised 28 dialysis patients (15 females, 13 males, age 22-78 years, dialysis sessions three times weekly 4-5 h, mean duration of dialysis treatment 4-99 months) and 20 healthy subjects (9 females, 11 males, age 18-56 years). The absolute number of leukocytes in the peripheral blood, the leukocyte mobilization (chemotactic activity) and the phagocytic activity of PMNs were tested in patients before (n = 28), and after (n = 18) reaching the target hematocrit of 30% and during the follow-up period. No alteration in the total leukocyte number (PMN, monocytes, lymphocytes) in the peripheral blood during rhu-EPO therapy could be seen. The phagocytic activity of PMNs slightly improved during the follow-up period whereas the decreased chemotactic activity remained unchanged.

Adolescent↗

[Selenium and antioxidant status in various diseases].

All healthy mammalian organisms are characterized by an equilibrium between the occurrence of highly reactive oxygen species and their destruction by anti-oxidants. Numerous diseases go hand in hand with a disturbance of the homoeostatis. In order to avoid or minimize the destructive effect of the oxidant stress on biological structures, therapies utilizing drugs with anti-oxidant effects are increasingly being applied. Preconditions for these therapies are a characterisation and a follow-up of the anti-oxidant status in the diseased organism. In the course of the present study selenium, glutathione peroxidase and malondialdehyde were determined in patients with various clinical pictures (terminal renal insufficiency, septic shock, high-risk gravidieties, arterioscleroisis, pulmonary carcinoma, acute myocardial infarction, test patients taking the contraceptive pill). Patients with terminal renal insufficiency and those suffering from septic shock syndromes clearly show a selenium decrease in serum and whole blood as well as a drop in the GSH-Px-activity, and increased malondialdehyde concentrations in the serum. Both are a reflection of an increased lipid peroxidation. First results of a selenium therapy are available for patients with therminal renal insufficiency and post-traumatically induced renal failure. The interpretation of the findings in the categories "high-risk gravidity" and "women on the contraceptive pill", which show a normal GSH-Px-activity and significantly increased malondialdehyde concentrations, seems problematic. The organism counteracts an increased lipid peroxidation with a normal plasma-GSH-Px-activity, clearly a sign of a still normal anti-oxidant potential.

Acute Kidney Injury↗

Differences in intravenous and subcutaneous application of recombinant human erythropoietin: a multicenter trial.

The aims of this clinical study were to compare the maintenance doses for intravenous (i.v.) and subcutaneous (SC) administration of recombinant human erythropoietin (rhEPO) and to investigate whether there is any difference in the increase of the packed cellular volume (PCV) per week under i.v. and SC administration of rhEPO from two production sites (Genetics Institute, Cambridge, USA; and Boehringer Mannheim, Penzberg, Germany). A total of 90 patients suffering from end-stage renal disease were included in the study. All patients had already been treated for at least 6 months with chronic hemodialysis. The study was carried out as a randomized, multicenter parallel group comparison study with a 1-week pretreatment phase, a subsequent 8-week double-blind phase, and a final open phase. The final open phase consisted of a correction phase and a maintenance phase. The production site had no influence on the PCV increase per week, and there were no differences with respect to tolerability. The median rhEPO dose required to maintain the target PCV of 30 to 35 vol.% was 33 U/kg body weight three times a week in the i.v. group compared with 22 U/kg in the SC group (i.e., an average of 30% less with SC administration). Development or aggravation of hypertension under rhEPO therapy was observed, especially during the correction phase and more frequently in the SC group than in the i.v. group. During the maintenance phase, there was no essential difference between the two groups.

Adult↗

[What should the general practitioner know about diagnosis and treatment of acute kidney failure?].

Acute renal failure (ARF) is defined as a renal insufficiency of sudden onset (increase of creatinine and urea in the serum) combined with or without oliguria (less than 500 ml of urine per day). Nephrotoxins (drugs, contrast medium) or renal ischemia (hypovolemia, hypotension, shock, septicemia, treatment with CEI) may affect the renal tubulus through several pathways, all of which may result in ARF. Ultrasound allows to distinguish hydronephrosis from ARF which is characterized by increased width of the parenchyma and low echodensity of the medulla. ARF is usually reversible. If conservative therapy fails, dialysis treatment is necessary.

Acute Kidney Injury↗

Haemodialysis-associated beta 2M amyloidosis: current controversies.

Beta 2M amyloidosis is a major complication of long-term haemodialysis. Beta 2M, the precursor molecule of amyloid fibrils, accumulates in renal failure because of diminished renal excretion. Whether, in addition, a minor increase of synthesis occurs in dialysed patients is still controversial. Beta 2M amyloidosis differs from most other forms of amyloid by its preferential osteoarticular location. This points to some peculiar role of the microenvironment in the synovial space, which is currently poorly defined. A finding which remains so far unexplained is the more delayed appearance of beta 2M amyloidosis in patients dialysed with polyacrylonitrile membranes. In principle, however, beta 2M amyloidosis is seen with all dialysis modalities and possibly even before maintenance dialysis. Differences between treatment modalities relate either to removal of beta 2M or some aspect of bioincompatibility, e.g. proteolytic processing. Finally, the exact chemical nature of amyloid fibrils, i.e. whether they constitute native beta 2M molecules or processed molecules, is currently controversial.

Amyloid↗

Calcium carbonate (CaCO3): an efficient and safe phosphate binder in haemodialysis patients? A 3-year study.

In an uncontrolled study, 22 dialysis patients (46 +/- 14 years, duration of dialysis 20 +/- 11 months) were treated with CaCO3 over a period of up to 3 years to lower their serum phosphate. The use of 4.5-9 g CaCO3 daily over a period of 9 months led to a reduction of mean serum phosphate from 2.51 to 1.51 mmol/l in 77% of patients, with a simultaneous increase in mean calcium concentration from 2.23 to 2.47 mmol/l, and an improved control of secondary hyperparathyroidism by reduction in mPTH from 1552 to 1032 pg/ml and in APH activity from 6.25 to 4.55 mumol/s/l. In long-term CaCO3 treatment of up to 3 years, however, a constant effective phosphate reduction could not be achieved. There was a progression (77%) of pre-existing microcalcification and a new appearance (42%) of microcalcification in vessels and soft-tissue areas of the hand. The percentage of patients with soft-tissue calcification increased from 43 to 67% during a treatment period of 3 years. We conclude that CaCO3 alone is not suitable on a long-term basis for phosphate reduction in dialysis patients.

Adult↗