Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Hemofiltration”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1982

Elimination of low molecular weight proteins during hemofiltration.

In patients on regular dialysis treatment, uremic symptoms (anemia, osteopathy, myopathy, neuropathy, and disorders of carbohydrate, fat, and protein metabolism) may be partly due to an accumulation of low molecular weight (MW) proteins (10,000 to 60,000 daltons). We tested this hypothesis using membranes with a higher permeability than conventional Cuprophan membranes. The primary aim of the study was to test the cutoff of various hemofilters (Cuprophan [Highflux], polyamide [FH 20], cellulose acetate [Duoflux], and polyacrylonitrile [Hospal RP 7 + 8 and Asahi PAN]) under in vivo conditions. In addition the effects of hemofiltration on plasma low molecular weight protein concentrations, polyneuropathy, and autonomic insufficiency were also tested in a long-term (six-month) study using the membrane with the highest cutoff and most constant sieving coefficient, i.e., Highflux. Low MW proteins with a defined MW were used as marker substances. Sieving coefficients of beta 2-microglobulin, lysozyme, retinol-binding protein, alpha 1-glycoprotein, alpha 1-antitrypsin, prealbumin, albumin, and transferrin were determined during a four-hour hemofiltration (20 L ultrafiltrate). Proteins were analyzed using an immunodiffusion technique. In the long-term study, motor nerve conduction velocity, the Schellong test, and Valsalva maneuver were tested prior to and three and six months after hemofiltration therapy. Highflux, Duoflux, and FH 202 membranes were permeable to proteins with molecular weights up to 15,000 daltons, and the Highflux module had the most constant sieving coefficient during hemofiltration. In the six-month hemofiltration study with the Highflux filter, plasma beta 2-microglobulin and lysozyme decreased significantly as expected. Parameters of polyneuropathy and autonomic insufficiency were slightly improved.

Adult↗
PubMed1980

Hemofiltration and plasma dopamine beta-hydroxylase activity.

Plasma dopamine beta-hydroxylase (DBH) activity was studied in control patients (n = 70), in patients on maintenance hemodialysis (n = 79) and in patients on maintenance hemofiltration (n = 19). DBH activity was significantly lower in patients on hemodialysis (32.4 +/- 20.6 IU) and hemofiltration (32.8 +/- 29.7 IU) than in control individuals (50.0 +/- 29.3 IU). Sequential measurements of DBH in patients on maintenance hemofiltration failed to show a fall of plasma DBH with time. 7 patients were studied during one session of hemodialysis and one session of hemofiltration. External fluid balance was identical. The change of DBH during hemodialysis and hemofiltration was not significantly different. Such rise of DBH as occurs may entirely be accounted for by hemoconcentration.

Adult↗
PubMed1998

Pharmacokinetics of Catecholamines During Hemofiltration in Pediatric Patients.

BACKGROUND: Continuous hemofiltration is used in pediatric patients with acute renal failure. Many of these patients are treated with catecholamines for hemodynamic instability. The authors studied the pharmacokinetics of dopamine and dobutamine on patients undergoing continuous venovenous hemofiltration. METHODS AND RESULTS: Three critically ill pediatric patients with acute renal failure and cardiovascular instability treated with hemofiltration and intravenous infusion of dopamine and/or dobutamine were entered into the study. Blood samples were drawn at steady-state levels from the arterial port (inflow) of the hemofilter, from the venous port (outflow) of the hemofilter, and from the ultrafilter. Sixteen (n = 16) pharmacokinetic measurements were made, six (n = 6) for dopamine and 10 (n = 10) for dobutamine. The clearance of dopamine by the hemofilter was 0.078 +/- 0.011 mL/kg/min, and for dobutamine it was 0.036 +/- 0.008 mL/kg/min. On the average, 0.56% of the dopamine dose and 0.13% of the dobutamine dose was removed by the hemofilter. CONCLUSIONS: The pharmacokinetics of dopamine and dobutamine at the dosage range of 5-25 µg/kg/min are not altered by continuous hemofiltration. Relative to total plasma clearance, negligible amounts of the drug were removed. The dosage of these catecholamines need not be adjusted during continuous hemofiltration.

Journal Article↗
PubMed1977

Parathyroid hormone, calcium and phosphate balance in hemofiltration.

The acute changes in calcium, phosphate and parathyroid hormone have been examined in chronic renal failure patients under-going hemofiltration therapy and the results compared to a similar group treated by hemodialysis. In both groups there was a significant increase in Catot (0.32 mEq/1 for hemodialysis; 0.56 m Eq/1 for hemofiltration) with Ca++ remaining constant. Plasma phosphate and parathyroid hormone decreased during hemofiltration. Calcium balances were slightly positive and phosphate balances distinctly negative in all cases. To date there is no indication of induced osteodystrophy during hemofiltration therapy, although long-term studies are needed. However, the present results indicate, that hemofiltration more closely approaches the physiological situation than conventional hemodialysis.

Calcium↗
PubMed1986

Total body fluid volume determination based on urea kinetics in hemofiltration as an index of basal body weight in uremic patients.

Assuming that urea is distributed uniformly within the total body water, urea-space or total body fluid volume was determined in six uremic patients based on urea kinetics in hemofiltration. The total body fluid volume before hemofiltration was 36.0 +/- 3.6 L (61.8 +/- 2.6% BW) and after hemofiltration 32.5 +/- 3.4 L (59.3 +/- 2.8% BW), suggesting that the total body fluid volume was nearly normalized by hemofiltration. It is concluded that urea-space, easily measurable based on urea kinetics during hemofiltration, is useful in evaluating the fluid balance in patients undergoing artificial kidney therapy.

Blood↗
PubMed1983

Hemodynamics in hemofiltration.

To study the established but not well understood phenomenon of improved intratreatment vascular stability during hemofiltration the same 10 stable hemodialysis patients were investigated during one hemodialysis and one hemofiltration treatment. Both treatments were matched in regard to linear fluid withdrawal (3 kg/240 minutes), small molecule removal rate (Curea 120 ml/min). Sodium (140 meq/l) and acetate (35 meq/l) concentration in dialysate and replacement fluid were identical. Outcome measures included mean arterial blood pressure, total peripheral vascular resistance by thermodilution, plasma noradrenaline concentration as index of sympathetic activity and sodium loss per treatment. Blood pressure was maintained during hemofiltration, while total peripheral vascular resistance and plasma noradrenaline concentrations increased. During hemodialysis mean arterial blood pressure fell significantly, total peripheral resistance and plasma noradrenaline concentrations remained unchanged. During both treatment modalities sodium loss was comparable. It is concluded, that the improved hemodynamic stability during hemofiltration is due to a maintained physiologic response to ultrafiltration, which is impaired during hemodialysis. Vascular stability during hemofiltration is not due to sodium retention relative to hemodialysis.

Adult↗
PubMed1982

Studies of carbohydrate metabolism after hemodialysis and hemofiltration in uremic patients.

To assess the effects of dialysis or hemofiltration on carbohydrate metabolism in uremia, we performed intravenous (IV) glucose tolerance tests (IV GTTs) after an overnight fast 48 hours following the last treatment in ten patients with chronic renal failure. Samples were obtained for plasma glucose, insulin, glucagon, and growth hormone levels throughout the GTTs in addition to basal samples for levels of plasma potassium and bicarbonate. The IV GTTs were performed at the end of a four-month period of standard hemodialysis (period 1) and then at the end of a four-month period of hemofiltration (period 2). Patients had mild glucose intolerance that did not change after hemofiltration, although the exaggerated insulin responses to glucose administration did significantly decrease in period 2. The fasting hyperglucagonemia did not decrease after hemofiltration but exhibited normal suppression with IV glucose. Levels of basal plasma bicarbonate and basal plasma potassium did not change significantly in period 2. Further studies investigating the beneficial metabolic effect of hemofiltration would seem to be indicated based on the data reported herein.

Adult↗
PubMed1980

Effect of isoosmolar volume reduction during hemofiltration on plasma antidiuretic hormone in patients with chronic renal failure.

The effect of isoosmolar volume reduction on plasma ADH level was studied in 8 patients with chronic renal failure utilizing hemofiltration technique. Plasma ADH fell significantly (P less than 0.001) after one hour of hemofiltration despite volume reduction which was expected to elevate the ADH level. After two hours of hemofiltration, ADH remained low in 5 patients and increased in 3. Post-hemofiltration mean blood pressure was generally lower in patients whose ADH rose than those whose ADH remained low. The two groups were otherwise comparable with respect to total fluid loss, hemofiltration rate, and fluid removed expressed as percent body weight. It can thus be suggested that in these patients a rise in plasma ADH in response to fluid reduction may require a fall in the arterial blood pressure below a critical level. While the rise in plasma ADH observed with continued fluid removal in some patients can be readily explained, we have no clear explanation for the paradoxical initial fall of ADH in all patients and subsequent maintenance of low levels observed in the majority of patients. This unusual ADH response to isoosmolar volume reduction may represent some unidentified mechanism of ADH regulation in patients with end-stage renal disease.

Adult↗
PubMed1993

Hemofiltrability of histamine H2-receptor antagonist, nizatidine, and its metabolites in patients with renal failure.

To study if an H2-receptor antagonist, nizatidine, and its metabolites [N-2-monodesmethylnizatidine (N-2-MDMN) and nizatidine sulfoxide (nizatidine S-Ox)] would be removed by an arteriovenous hemofiltration, the authors measured their plasma concentrations and amounts recovered in ultrafiltrate during 11 sessions of an intermittent hemofiltration performed in seven patients with renal failure who were given an oral administration of nizatidine (150 mg). The concentrations of the parent drug and its metabolites in plasma and ultrafiltrate were determined with a high-performance liquid chromatography with ultraviolet absorbance detection. The mean (+/- standard deviation [SD]) amounts of nizatidine removed by the procedure performed at the mean ultrafiltration rate of 18 (range, 11-25) mL/min over the mean duration of 179 (60 to 300) minutes accounted for 1.9 +/- 1.4% of the dose administered. The corresponding values for N-2-MDMN and nizatidine S-Ox were 0.3 +/- 0.2% and 0.2 +/- 0.2% of the molar dose of nizatidine, respectively. There was a significant correlation between the filtration rate and the hemofiltration clearance of nizatidine (r = .94, P < .001) or its active metabolite, N-2-MDMN (r = 0.83, P < .01), indicating that the sieving coefficient (Sc), an index of filtration efficiency, for these compounds is largely constant (0.59 and 0.67 for nizatidine and N-2-MDMN, respectively) under the current hemofiltration conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Diabetic coma with deep hypothermia. Successful resuscitation with hemofiltration].

A 41-year-old woman with severe juvenile diabetes mellitus suffered from profound hypothermia after loss of thermoregulation in diabetic ketoacidosis. She was found unconscious, without measurable blood pressure; the electrocardiogram (ECG) showed bradycardia of 30 min and the rectal temperature was 23.7 degrees C. The patient received mechanical ventilation, fluid therapy, warmed gastric lavage, and, unfortunately, inotropic medication. She was transferred to a department of cardiac surgery in order to continue the therapy with cardiopulmonary bypass (CPB). On arrival, the patient had a rectal temperature of 27.3 degrees C, the ECG showed an absolute arrhythmia with a frequency of 70/min, and the blood pressure was 63/43 mmHg. We decided to use a rapidly available but not highly invasive venovenous hemofiltration technique for slowly rewarming the patient. Vascular access was achieved by percutaneous femoral vein cannulation with a Shaldon catheter. The hemofiltration system (Gambro AK-10, Gambro AB, Sweden) was instituted with a blood flow rate of 200 ml/min. The hemofiltration monitor controls the pumps for filtering and substituting fluid volumes and allows the infusion solutions to be heated up to 40 degrees C. Sinus rhythm resumed without antiarrhythmic medications at a temperature of 29.5 degrees C, and within 8 h the patient was rewarmed to 35.5 degrees C. After treatment of the adult respiratory distress syndrome caused by pneumonia, she was discharged from the intensive care unit to complete treatment with no evidence of any permanent organ damage. We conclude that hemofiltration may be the method of choice for rewarming deeply hypothermic patients when their circulation is preserved.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2002

Super high flux hemofiltration: a new technique for cytokine removal.

OBJECTIVE: To test whether hemofiltration using a hemofilter with large pores (super high flux hemofiltration) achieves effective cytokine removal. DESIGN: : Ex vivo study. SETTING: Laboratory of an intensive care unit in a tertiary hospital. PATIENTS AND PARTICIPANTS: Five healthy volunteers. INTERVENTIONS: Blood was spiked with 1 mg of endotoxin and then circulated through a closed hemofiltration circuit with a large pore polyamide super high flux hemofilter (nominal cut-off point: 100 kDa). Hemofiltration was conducted at 1 l/h or 6 l/h of ultrafiltrate flow. Samples were taken from the arterial, venous and ultrafiltration sampling ports. MEASUREMENTS AND RESULTS: Sieving coefficients (SC) above 0.6 were achieved for interleukin (IL)-1beta, IL-6 and IL-10 and SCs above 0.3 were achieved for IL-8 and TNF-alpha at 1 l/h. SCs of all cytokines (except IL-1) were reduced when the ultrafiltration rate was increased from 1 l/h to 6 l/h ( p<0.01), but cytokine clearances still increased ( p<0.01). The highest SC for albumin was 0.1 at 1 l/h and fell to 0.01 at 6 l/h. No adsorption of cytokines and albumin was observed. CONCLUSION: High volume ultrafiltration using a super high flux filter achieved cytokine clearances comparable to, or greater than, those currently achieved for urea during standard continuous renal replacement therapy.

Albumins↗
PubMed1993

Hemofiltration modifies complement activation after extracorporeal circulation in infants.

Complement and fibrinolytic factors were measured in 9 infants undergoing hemofiltration immediately after cardiopulmonary bypass in an attempt to reduce activation of these systems. Plasma levels of C3a, C5a, and terminal complement complexes increased during bypass by 460%, 85%, and 745%. Plasma levels were reduced after hemofiltration in 8 of the 9 infants, and C3a and C5a fractions were recovered in the ultrafiltrate. The observed activation of the fibrinolytic system seemed to be unaltered by hemofiltration. Fibrinolytic factors were not filtered. Our study shows that increased concentrations of complement factors in the plasma after bypass in infants may be reduced by hemofiltration.

Complement Activation↗
PubMed1989

Removal of intracellular waste products by hemofiltration.

Because the total amount of waste products removed by hemofiltration can be measured exactly, it was divided into two components, that removed from the extracellular compartment and that removed from the intracellular compartment, using inulin as a marker for extracellular fluid in five uremic patients treated with hemofiltration in the postdilution mode. The amount removed from the extracellular compartment as a proportion to the total amount removed from the whole body by hemofiltration was 86.5% +/- 10.6% for guanidinosuccinic acid, 69.1% +/- 15.6% for sodium, 59.4% +/- 3.3% for uric acid, 56.4% +/- 2.1% for inorganic phosphate, 45.6% +/- 5.3% for creatinine, 43.1% +/- 7.2% for potassium, 42.9% +/- 3.1% for guanidinoacetic acid, 42.5% +/- 7.5% for methylguanidine, 37.2% +/- 8.4% for chloride, 36.3% +/- 2.8% for urea, and 6.9% +/- 2.9% for glucose. These results show that extracellular substances such as sodium and guanidinosuccinic acid were removed mainly from the extracellular compartment. On the other hand, glucose was removed only from the intracellular compartment, since blood glucose level is regulated. Although uric acid, inorganic phosphate, creatinine, potassium, guanidinoacetic acid, and methylguanidine are intracellular substances, they accumulated also in the extracellular fluid in renal failure, and were removed from both compartments, intracellular as well as extracellular, by hemofiltration.

Body Fluids↗
PubMed1991

Efficacy of continuous arteriovenous hemofiltration with dialysis in patients with renal failure.

OBJECTIVE: To document the efficacy of continuous arteriovenous hemofiltration with dialysis following renal failure, without protein restriction, and to explore the magnitude and clinical applications of total daily urea clearance. DESIGN: A noncomparative, descriptive account of a case series. Data were collected prospectively and analyzed retrospectively. SETTING: A tertiary care facility in a statewide emergency medical services system. PATIENTS: Twenty-eight patients with renal failure were supported by continuous arteriovenous hemofiltration with dialysis in a critical care unit during a 14-month period (21 patients with multitrauma; three patients with soft tissue infections; and four patients with multisystem organ failure who had been transferred from other hospitals). Renal failure was most commonly due to multisystem organ failure or associated with adult respiratory distress syndrome. RESULTS: Continuous arteriovenous hemofiltration with dialysis days totaled 308 (mean 10.9). All patients received full protein alimentation (mean protein load 131 g/day). The blood urea nitrogen concentration was controlled, generally to 40 to 75 mg/dL (14.3 to 26.7 mmol/L) within 3 to 5 days. Total daily urea clearance ranged from 15 to 21 g/day. Five (18%) of the 28 patients survived. CONCLUSION: Continuous arteriovenous hemofiltration with dialysis appears to be effective for the control of blood urea nitrogen and clearance of urea. This modality also permits full protein alimentation. Total daily urea clearance can be calculated easily and may have important clinical uses and implications.

Adult↗
PubMed1994

Functional characteristics of pediatric veno-venous hemofiltration.

OBJECTIVE: To evaluate the functional characteristics of continuous veno-venous hemofiltration in a pediatric size animal model. DESIGN: Prospective trial. SETTING: Animal laboratory at a large university-affiliated medical center. SUBJECTS: Four-week old lambs (weight 12.2 +/- 1.3 kg). INTERVENTIONS: Veno-venous hemofiltration was performed in anesthetized lambs (n = 5, 12.2 +/- 1.3 kg) using a standard pediatric hemofilter and pumped blood and ultrafiltrate. We compared postdilution, predilution, and hemofiltration with counterflow dialysis. MEASUREMENTS AND MAIN RESULTS: At net ultrafiltrate flows of 200, 400, and 600 mL/hr, we measured system pressures and urea clearance. Stable blood flow could reproducibly be achieved up to 140 mL/min (10 mL/kg/min); at higher flow demand, tubing collapse occurred. At blood flow rates of 5 to 10 mL/kg/min, ultrafiltrate flow of 1 mL/kg/min would create negative filter compartment pressure but consistently less negative than -500 mm Hg. During postdilution, predilution, and counterflow dialysis, urea clearance was virtually equal to ultrafiltrate flow. There was no increase in urea clearance when adding predilution or dialysis to basic postdilution. CONCLUSIONS: Veno-venous hemofiltration, using small filters and circuits in a pediatric size animal, can achieve stable blood flow up to 10 mL/kg/min. At this flow, ultrafiltrate flow of 1 mL/kg/min can produce a urea clearance of 1 mL/kg/min while keeping filter compartment pressure above maximal recommended negative pressures. Addition of dialysis in this nonuremic model did not increase urea clearance.

Animals↗
PubMed1998

Removal of piperacillin in critically ill patients undergoing continuous venovenous hemofiltration.

OBJECTIVE: Continuous hemofiltration is now widely used in the intensive care unit. Our study aimed to assess the removal of piperacillin under continuous hemofiltration and to define a suitable dosage regimen of administration. DESIGN: Prospective study of blood and ultrafiltrate concentrations of piperacillin to assess the pharmacokinetics of the antibiotic. SETTING: The medical intensive care unit of a teaching hospital. PATIENTS: Ten patients were included in the study. Six patients were receiving their first dose of piperacillin (group 1) and four had already been treated for 2 to 6 days (group 2). The mean Simplified Acute Physiology II score was 74 +/- 6 (SEM), and the number of organ failures was 3.6 +/- 0.3 (range 3 to 5). Renal failure was related to septic shock in seven patients and to cardiogenic shock in three patients. Seven patients were anuric. Hepatic dysfunction was present in four of the ten patients. INTERVENTIONS: Patients were treated with continuous venovenous hemofiltration using a hollow polysulfone capillary fiber. Piperacillin (4 g) was injected intravenously over 20 mins. Arterial blood and ultrafiltrate were sampled immediately before the injection and then every hour until 8 hrs after injection time. Piperacillin concentrations were assayed using high performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS: In group 1, the mean serum peak concentration of piperacillin was in the normal range (125 +/- 21 mg/L), but trough values were higher (48 +/- 8 mg/L) than in normal subjects. In group 2, trough values before the injection were increased in all patients (188 +/- 71 mg/L). At T1, blood peak concentration reached 470 +/- 127 mg/L. A small amount of piperacillin was retrieved from the ultrafiltrate. The elimination half-life was 5.1 +/- 1.4 and 4.8 +/- 1.4 hrs in groups 1 and 2, respectively. CONCLUSIONS: Piperacillin was not removed to a significant extent during continuous hemofiltration. Further, in the intensive care unit, patients in shock with multiple organ failure such as liver failure might behave differently from patients with stable end-stage renal disease. A 4-g dose of piperacillin twice a day is recommended in such patients.

Aged↗
PubMed2003

Continuous veno-venous hemofiltration may improve survival from acute respiratory distress syndrome after bone marrow transplantation or chemotherapy.

PURPOSE: Acute respiratory distress syndrome (ARDS) may result from immunologic activity triggered by irradiation and/or chemotherapy. Hemofiltration removes plasma water and soluble components below 25 kilodaltons. The authors hypothesized that early hemofiltration might attenuate the inflammatory component of ARDS, resulting in increased survival in immunocompromised children and young adults. METHODS: Ten children (6 bone marrow transplantation, 3 chemotherapy, 1 lymphoma/hemophagocytosis) with ARDS (Pao2/Fio2 94 +/- 37 torr) received early continuous veno-venous hemodiafiltration as adjunctive therapy for respiratory failure, regardless of renal function. Six children had normal urine output and initial serum creatinine (range 0.1-1.2 mg/dL); four had renal insufficiency (initial creatinine 1.7-2.4 mg/dL). Hemofiltration was instituted coincident with intubation. Respiratory failure was precipitated by Enterobacter sepsis in two patients and by Aspergillus in one. RESULTS: Hemodiafiltration was performed for 13 +/- 9 days. A high rate of clearance was achieved (52 +/- 17 mL/min/1.73 m2). Duration of mechanical ventilation was 14 +/- 9 days. Nine of the 10 children were successfully extubated; 8 survived. CONCLUSIONS: Early hemofiltration may improve survival from ARDS following bone marrow transplantation or chemotherapy. Possible mechanisms include strict fluid balance, immunomodulation through filtration of inflammatory constituents, and immunomodulation through intensive extracellular water exchange that delivers biochemicals to organs of metabolism as well as the hemofilter.

Adolescent↗
PubMed2005

Severe lactic acidosis complicating metformin overdose successfully treated with high-volume venovenous hemofiltration and aggressive alkalinization.

OBJECTIVE: In this report of a near-fatal metformin ingestion successfully treated with alkalinization and high-volume hemofiltration, we discuss the management of severe lactic acidosis and demonstrate that early aggressive intervention resulted in a positive outcome. DESIGN: Case report. SETTING: A tertiary pediatric intensive care unit. PATIENT: The patient was a healthy 14-yr-old female found by a sibling following a seizure of unknown duration, thought to be secondary to hypoglycemia as a consequence of a self-ingestion of metformin, atenolol, and diclofenac. She responded well to advanced resuscitation but progressively developed severe lactic acidosis, bradycardia, and hypotension in addition to persistent hypoglycemia. The peak lactate level was 37.5 mmol/L with an albumin corrected anion gap of 65 mmol/L. INTERVENTIONS: She was treated with high-volume venovenous hemofiltration and aggressive alkalinization therapy. The latter facilitated control of severe acidosis, whereas the hemofiltration removed the ingested drugs in addition to endogenously produced lactate precipitated by metformin. CONCLUSIONS: In this case, early and aggressive treatment of the acidosis and cardiovascular compromise with inotropes, venovenous hemofiltration, and large doses of sodium bicarbonate in metformin overdose resulted in a successful outcome even in the presence of severe acidosis and very high lactate levels.

Acidosis, Lactic↗