Hours Of Hemodialysis Research Articles

1290 TRANSIENT HYPERAMMONEMIA OF PREMATURITY (THP): RESPONSE TO HEMODIALYSIS (HD)

A 2.5 kg male infant delivered at 35 weeks gestation developed generalized seizure activity, then coma at 24 hours of age. Plasma ammonia at 36 hours of age was 2575 μg/dl. The concentration of citrulline in the blood was 109 μM, that of arginine was 145 μM; argininosuccinate was absent, and urinary orotic acid excretion was 46 μg/mg creatinine. Volatile fatty acids in plasma were normal as was the plasma glycine concentration (530 μM). A diagnosis of transient hyperammonemia of prematurity was made and therapy begun. Despite four three-volume exchange transfusions and a constant arginine infusion of 4 mM/kg/day in a single 24 hour period, which increased the plasma arginine and ornithine to greater than 2000 μM, the plasma ammonia concentration remained greater than 1000 μg/dl. The infant underwent three hours of hemodialysis performed via an “umbilical shunt” at 62 hours of age. This lowered ammonia from 2184 to 275 μg/dl and was associated with complete reversal of neurological depression. Ammonia clearance by HD was calculated to be 40 ml/min at a blood flow of 60 ml/min. Ammonia levels continued to fall without further therapy and remained within the normal range (<100 μg/dl) for the duration of hospitalization even after commencement of formula feedings. We conclude that HD is an effective therapy for THP and should be considered in centers equipped for this procedure.

Pharmacokinetics of amantadine hydrochloride in subjects with normal and impaired renal function.

Amantadine is useful for the prevention and treatment of influenza A and for the treatment of Parkinson's disease and drug-induced extrapyramidal disorders. We have compared the pharmacokinetics of amantadine in patients with impaired or negligible renal function to that in normal subjects. The half-life of elimination in subjects with normal renal function was 11.8 +/- 2.1 hours (range, 9.7 to 14.5 h). Eight patients with various degrees of renal insufficiency (creatinine clearance from 43.1 to 5.9 mL/min . 1.73 m2) had half-lives of elimination from 18.5 h to 33.8 days. We also studied 10 patients on thrice-weekly hemodialysis. Assuming complete bioavailability of the drug, less than 5% of the dose was removed by each 4-hour hemodialysis. The mean half-life of elimination during chronic hemodialysis was 8.3 days (range, 7.0 to 10.3). We present guidelines for use of amantadine in patients with impaired renal function, including those on maintenance hemodialysis.

Amantadine hydrochloride pharmacokinetics in hemodialysis patients.

To study the fate of amantadine hydrochloride in patients with renal failure, we gave 100 mg orally to 12 such patients immediately after hemodialysis. Plasma levels did not decrease between 24 and 44 hours after drug ingestion, suggesting an extremely poor total body clearance. Apparent volume of distribution was 5.1 +/- 0.2 (SEM) L/kg of body weight. Between 44 and 48 hours, as a result of 4 hours of hemodialysis, the mean plasma drug level decreased from 268 to 225 ng/mL (P less than 0.001). Dialyzer clearance was 67.0 +/- 3.9 mL of plasma per minute. The total quantity of drug removed by the dialysis treatment, however, was only 3.9 +/- 0.25 mg. The average half-life of amantadine in eight patients studied while receiving maintenance hemodialysis was 24.3 +/- 2.4 h of dialysis administered over approximately 13 days. Plasma half-life in six nonuremic control subjects was 12.2 +/- 1.6 h. Amantadine is poorly excreted in dialysis patients and has a large volume of distribution. The amount removed by a single dialysis is only a small fraction of the total body store.

Plasma amino acids in the anephric goat.

As part of an evaluation of the Spanish brush goat (Capra hiricus) as an anephric animal model, free amino acids were determined in plasma before and after 4-hour hemodialysis perio

18-Hydroxy-11-deoxycorticosterone in Hypertensive Uremic Patients during Hemodialysis

The present study was carried out in 25 hypertensive uremic patients on regular 4 h dialysis, 3 times a week. Plasma 18-hydroxy-11-deoxycorticosterone (18-OH-DOC), aldosterone (PA) and corticosteroids were determined by radioimmunoassay and competitive protein binding technique before and at the end of the 1st, 2nd and 3rd hour of hemodialysis. Plasma 18-HD-DOC was normal before dialysis and did not change significantly during hemodialysis, whereas body fluids and electolytes decreased progressively. No correlation was observed between blood pressure and 18-OH-DOC during dialysis. 18-OH-DOC did not correlate with PA which decreases progressively during hemodialysis and was correlated to plasma corticosteroids only at the 3rd hour of dialysis, probably on account of the enhanced influence of ACTH on the adrenal cortex.

Late Complications of Long-term Hemodialysis in Children: Clinical Aspects and Some Measurable Variables Concerning Parathyroid Hormone, Divalent Ions, Acid-base Metabolism, Anemia, Nutrition, Growth and Survival Data

AbstractNineteen pediatric patients, ranging in age from 5 to 17 years, were followed for up to 59 months and 3,129 hemodialysis procedures were done. The known duration of renal diseases before hemodialysis was 6 ± 3 years. The clinical complications consisted of 5 patients with sepsis, 2 patients with malignant hypertension, 6 patients with congestive heart failure, 3 patients with seizure disorders and 1 patient with intractable ascites. Radiologic evidence for renal osteodystrophy was present in 4 patients, although elevated levels of parathyroid hormone were documented in all patients after 6 months of hemodialysis.Hypocalcemia (8.4 ± 1.7mg./dl.) was documented before initiation of hemodialysis and normalization occurred in only half of the patients after 6 months of hemodialysis with the dialysate calcium concentration of 3mEq./l. Pre-dialysis serum concentrations for magnesium (2.5 ± 0.4mg./dl.), phosphorus (5.3 ± 1.5mg./dl.), triglyceride (138 ± 31mg./dl.), cholesterol (180 ± 34mg./dl.) and total ...

Hemodialysis Clearance of Cimetidine

Hemodialysis clearance of cimetidine was determined in three patients and was found to range between 41.34 to 75.91 ml/min. Notwithstanding its substantial dialyzability, the amount of cimetidine removed by four hours of hemodialysis constituted only 8% to 14% of the administered dose. Accordingly, major dose adjustment on the days of dialysis treatment, as suggested in the available literature, may not be necessary.

Reduced protein loss during hemofiltration using Cuprophan membranes.

In a study of four patients treated with one hour of hemofiltration using Cuprophan membranes, followed by three hours of hemodialysis, it was found that protein loss during hemofiltration was minimal. Losses ranged from 0.013 mg/mg at a transmembrane pressure (TMP) of 300 mmHg to 0.012 mg/ml at a TMP of 600 mmHg. Protein loss was not dependent on TMP and varied from dialyzer to dialyzer. Protein levels in serum remained unchanged during the period of hemofiltration in these patients and no evidence of protein wastage was evident.

Time--concentration studies by high-performance liquid chromatography of metabolites removed during hemodialysis.

Reversed-phase high-performance liquid chromatography was used to study the efficiency of hemodialysis. The method, previously used to study uremic hemodialysate, was also found useful for analyzing other uremic biofluids, such as serum and urine. Samples of blood (centrifuged to obtain cell-free serum) and hemodialysate were simultaneously collected from selected patients at regular intervals during the entire 6-hour hemodialysis treatment. These samples were filtered through membranes to remove particulates and proteins and were then analyzed by use of a 60-cm muBondapak-C18 column, an aqueous sodium acetate/methanol gradient, and detection at 254 nm. The identification of components in the eluate was based on retention times, ultraviolet absorption spectra, and mass spectra. From the amounts of several metabolites in the various physiological fluid pools during hemodialysis, we concluded that they mostly originate from tissue fluids. We also observed that the concentrations of most components in serum and hemodialysate fluctuated regularly with time.

Hemodialysis. Effect on plasma levels of vitamin A and carotenoid.

PATIENTS with glomerulonephritis, chronic uremia, or nephrotic syndrome and uremic patients receiving maintenance hemodialysis 1 have elevated plasma vitamin A levels. 1-3 Plasma carotene levels are elevated in nephrotic patients. 3 Data concerning the influence of hemodialysis on vitamin A and carotene levels in plasma are lacking however. This study was designed to supply these data. Materials and Methods Hemodialysis was carried out on ten patients with chronic uremia, by means of a coil dialysis unit with 1.45 sq mm of dialyzing surface for eight hours twice weekly, by the standard technique. Blood samples were taken before and after eight hours of hemodialysis. Plasma was separated, and lipids were extracted with ethanol-petroleum ether (1:1 v/v). 4 Carotenoids were determined at 450 Armstrong units and vitamin A by the Carr-Price reaction 5 with a correction for carotenoids as described by Moore. 4 In some samples, β-carotene was separated from other carotenoids

Hemodialysis leukopenia. Pulmonary vascular leukostasis resulting from complement activation by dialyzer cellophane membranes.

Acute leukopenia occurs in all patients during the first hour of hemodialysis with cellophanemembrane equipment. This transient cytopenia specifically involves granulocytes and monocytes, cells which share plasma membrane reactivity towards activated complement components. The present studies document that complement is activated during exposure of plasma to dialyzer cellophane, and that upon reinfusion of this plasma into the venous circulation, granulocyte and monocyte entrapment in the pulmonary vasculature is induced. During early dialysis, conversion of both C3 and factor B can be demonstrated in plasma as it leaves the dialyzer. Moreover, simple incubation of human plasma with dialyzer cellophane causes conversion of C3 and factor B, accompanied by depletion of total hemolytic complement and C3 but sparing of hemolytic C1. Reinfusion of autologous, cellophane-incubated plasma into rabbits produces selective granulocytopenia and monocytopenia identical to that seen in dialyzed patients. Lungs from such animals reveal striking pulmonary vessel engorgement with granulocytes. The activated complement component(s) responsible for leukostasis has an approximate molecular weight of 7,000-20,000 daltons. Since it is generated in C2-deficient plasma and is associated with factor B conversion, it is suggested that activation of complement by dialysis is predominantly through the altermative pathway.

Hemodialysis in Methyprylon Overdose

Serial measurements of serum methyprylon concentration were made in the case of a 14-year-old girl who ingested an overdose of the drug. Our data indicate that, in the presence of high plasma levels of the drug, much longer half-lives than the usually reported four hours may be observed. It is postulated that saturation kinetics may be a possible mechanism for this observation. The striking clinical improvement after six hours of hemodialysis demonstrated the efficacy of this mode of treatment in our patient.

Hemodialysis of Acute Arsenic Intoxication With Transient Renal Failure

A striking reduction in serum arsenic level was achieved after four hours of hemodialysis in a patient with acute arsenic intoxication and transient renal failure. Quantitative dialysance of arsenic and a comparison of daily urinary excretion of arsenic with amount removed by dialysis suggested that hemodialysis is indicated in the treatment of acute arsenic intoxication if there is concomitant renal failure. In the presence of normal renal function, supportive measures, including dimercaprol (BAL in Oil) therapy, constitute the best available treatment.

Ouabain plasma level kinetics and removal by dialysis in chronic renal failure. A study in fourteen patients.

Ouabain plasma level kinetics and removal by dialysis were studied in 14 dialysis-dependent patients with chronic renal failure. Each received one 400 mug intravenous dose of unlabeled ouabain (9 patients also received 83 muCi of 3-H-ouabain) at the onset of a routine 4-hour hemodialysis. Plasma concentration fell rapidly the first few hours, and after 5 to 10 hours declined exponentially with a mean half-life of 50 plus or minus 19 (SD) hours. Ouabain recovery in dialysis bath was 11.5% plus or minus 2.2% the first 2 hours and only 3.4% plus or minus 0.5% the next 2 hours after an intravenous dose, due to rapid removal of ouabain from the extracellular fluid compartment by tissue uptake. Hence, hemodialysis is relatively ineffective for reducing ouabain body stores. Ouabain elimination in patients with chronic renal failure is significantly slower than in normal subjects (P smaller than 0.01), but significantly more rapid than that reported for digoxin (P smaller than 0.01) and digitoxin (P smaller than 0.01) in patients with chronic renal failure, a potentially useful characteristic in treating acute cardiac problems among such patients.

Crisis in the Health Service

Peak expiratory flow rate (PEF) was measured during haemodialysis in 30 unselected patients with chronic renal failure. The patients attended the hospital dialysis unit, where they received regular dialysis using a cuprophan dialyser with acetate buffered dialysate. Mean PEF had fallen by 60 l/min (13%) 30 minutes after the start of dialysis. In 10 of the 30 patients the fall in PEF was over 15%, the maximum fall being 32%. After the initial fall PEF increased throughout the next 2.5 hours of haemodialysis, but it fell again at five hours in the 14 patients who had been dialysed for four hours. During dialysis there was a reduction in blood white cell and platelet counts and in arterial oxygen tension at 30 and 60 minutes (p less than 0.05) and the white cell count and arterial oxygen tension were still reduced at three hours. The coincidence of the fall in PEF at 30 minutes and the fall in arterial oxygen tension suggests that bronchoconstriction might contribute to dialysis induced hypoxaemia by causing ventilation-perfusion disturbances. Appreciable airway dysfunction occurred in all the patients undergoing regular haemodialysis with new cuprophan dialysers and acetate buffered dialysate.

Flucytosine and amphotericin B: hemodialysis effects on the plasma concentration and clearance. Studies in man.

The efficacy of hemodialysis in removing flucytosine (5-fluorocytosine) and amphotericin B from blood was studied in eight adult patients with renal failure who required chronic hemodialysis; the results were correlated with the protein-binding of these drugs. Creatinine, flucytosine, and amphotericin B concentrations were measured immediately before and after dialysis, as well as in arterial samples of blood entering and leaving the artificial kidney after 2, 4, or 6 hours of hemodialysis. Clearances of flucytosine and creatinine by the artificial kidney were indistinguishable, and both increased linearly with blood flow through the dialyzer. These results were consistent with the minimal protein-binding (< 5%) found in vitro. In contrast to flucytosine, amphotericin B was highly (> 90%) protein-bound, poorly dialyzable, and the clearance rate by the artificial kidney ranged from 3% to 15% of that for creatinine. From these data, recommended dosage schedules for flucytosine and amphotericin B, when used to treat fungal infections in patients undergoing hemodialysis, were developed.

THE HAEMODYNAMIC RESPONSE TO CHRONIC RENAL FAILURE AS STUDIED IN THE AZOTAEMIC STATE

SUMMARY Fifty-nine haemodynamic studies were performed in 21 patients with chronic renal failure, usually on a day following at least 6 hours of haemodialysis. A miniature polyethylene tubing was “floated” into the right ventricle under manometric guidance without X-ray control. Indocyanine green was injected into the right ventricle for cardiac output estimations. Cardiac index, stroke volume, total peripheral resistance and mean arterial pressure were all found to be high. The total blood volume measured with 123 I isotope was not significantly expanded. Three patients with acute pulmonary oedema had normal central venous and right atrial pressures, showing that pulmonary capillary permeability is probably the principal factor in the padiogenesis of the “uraemic lung”, and that in these circumstances monitoring of central venous pressure is not reliable in warning the physician of impending pulmonary oedema. For this purpose it was useful to measure blood volume and right ventricular pressure.

Increased intracranial pressure from unsustained levels of plasma mannitol during hemodialysis.

Abstract A 33-year-old woman in barbiturate coma, who was given large doses of intravenous hypertonic mannitol before hemodialysis, deteriorated suddenly during the fourth hour of hemodialysis. Clinical and necropsy evidence indicated increased intracranial pressure. To determine whether the rapid removal of mannitol by dialysis might create a bloodbrain osmotic gradient favoring the development of intracranial edema, dogs were infused with mannitol and hemodialyzed as the mannitol was stopped. This was associated with an increase in cerebrospinal fluid pressure (CSFP) which did not occur if the plasma mannitol concentrations were sustained by continuous infusion or the addition of mannitol to the dialysate. A similar concentration of glucose did not prevent the CSFP rise. Increased CSFP was associated with CSF osmolality > plasma osmolality, caused by increased concentrations of CSF sodium chloride and a rapid reduction of plasma mannitol during dialysis. The clinical significance of these observations is discussed.

A hemodynamic evaluation of bilateral nephrectomy and hemodialysis in hypertensive man.

Three hypertensive men with end-stage primary renal disease were hemodynamically evaluated before and 3 to 4 weeks after bilateral nephrectomy and before and after 6 hours of hemodialysis with the twin coil artificial kidney. Conclusions include the following: (1) The height of the blood pressure and changes in plasma volume (P.V.) are not necessarily directly related in the early renoprival state. (2) Increased total peripheral resistance (TPR) plays an important role in maintaining elevation of blood pressure after nephrectomy. (3) We cannot document that bilateral nephrectomy has a beneficial effect on the hypertension of chronic renal failure during the first month of the anephric state. (4) Renin is not involved in maintaining elevated blood pressure after nephrectomy. (5) Increased sensitivity to ganglionic blockade may follow nephrectomy if P.V. decreases. (6) No evidence supports the existence of a "cardiodepressor" substance in uremia. (7) Increased blood pressure occasionally seen during hemodialysis is probably related to several factors (increased cardiac output, increased TPR). (8) P.V. may fall during hemodialysis even though body weight is maintained constant. (9) If P.V. is unchanged across hemodialysis, cardiac output usually does not change.

慈大式人工腎臓の研究

In order to improve the dialysis efficiency of the Jikei Electro-Dialyzer, the author constructed a new type of electro-dialyzer with many dialysis chambers. This new apparatus consist of three blood chambers and two bath fluid chambers. Each of them is placed alternately and combined with bolt and nut. Then, all the chambers are set into an outer bath fluid chamber with an electric board. The blood chambers are thin in thickness and consist of many more chambers as compared with the D-Type blood chambers. Consequently a larger dialysing surface can be obtained without enlargement in scale. Each chambers is place three dimentionally against the electric field, in order to maintain the characteristic function of the electro-dialysis.The author carried out various in vitro experiments on the fundamental dialysing efficiency of the apparatus with three blood chambers, and for in vivo experiments the author used six nephrectomized dogs to study the practical dialysing efficiency of the apparatus. Six nephrectomized dogs were hemodialyzed for 2 hours respectively, and observation were made on the changes of B. U. N. and blood electrolyte value before and after hemodialysis. Among the six dogs, three were hemodialyzed after 24 hours and two after 48 hours following bilateral nephrectomy. One was hemodialyzed by using two blood chambers after 24 hours following bilateral nephrectomy.The results obtained in vitro experiments are summarized as follows.1) This apparatus has a larger dialysing area as compared with the D-Type Electro-Dialyzer without enlargement of its scale.2) It needs a larger amount of bath fluid than the D-Type Electro-Dialyzer during 2 hours hemodialysis (about 271)3) Limitation of blood flow is 170cc/min, and the suitable flow is 100-120cc/min.4) When the temperature of this apparatus chamber reaches 35-37°C, an electric current density similar to that of D-Type Electro-Dialyzer can be obtained.5) Series connection proved more satisfactory than the parallel method.6) The dialysing efficiency of nonelectrolyte and electrolyte substance was better than the D-Type Electro-Dialyzer.7) Furthermore, there is a possibility that this apparatus can remove the body fluid by ultrafiltration. Ultrafiltration is caused by a rise of inner pressure of the blood chamber.The experimental results of bilaterally nephrectomized dogs are as follows.1) Approximately 15mg/dl B. U. N. can be removed hourly.2) As to the corrective ability of blood electrolyte imbalance, especially hyperpotassemia which was observed all nephrectomized dogs, a return to normal level was found after 2 hours of hemodialysis.3) When two blood chambers are applied, the B. U. N. dialysis efficiency consisted in the capacity to remove 7mg/dl hourly.This new apparatus which has many adventages as an effective artificial kidney can be used clinically for the treatment of uremia.