An evaluation of four modes of low-dose anticoagulation during intermittent haemodialysis.

INTRODUCTION: Intensive care participants that need dialysis frequently suffer from increased risk of bleeding. Standard intermittent haemodialysis (SHD) includes anticoagulation to avoid clotting of the dialysis system. The aim of this study was to clarify which of four different low-dose anticoagulant modes was preferable in reducing the exposure to i.v. unfractionated heparin (heparin) and maintaining patency of the dialysis circuit. METHODS: Twenty-three patients on SHD were included to perform haemodialysis with four modes of low-dose anticoagulation. For comparative analyses, patients served as their own control. Haemodialysis with a single bolus of tinzaparin at the start was compared to haemodialysis initiated without i.v. heparin but priming with (1) heparin in saline (H), (2) heparin and albumin in saline (HA), (3) heparin and albumin in combination with a citrate-containing dialysate (HAC), (4) saline and usinga heparin-coated filters (Evodial®). The priming fluid was discarded before dialysis started. Blood samples were collected at 0, 30 and 180 min during haemodialysis. Smaller bolus doses of heparin (500 Units/dose) were allowed during the modes to avoid interruption by clotting. FINDINGS: The mean activated partial thromboplastin (APTT) time as well as the doses of anticoagulation administered was highest with SHD and least with HAC and Evodial®. Mode H versus SHD had the highest rate of prematurely interrupted dialyses (33%, p = 0.008). The urea reduction rate was less with Evodial® vs. SHD (p < 0.01). One hypersensitivity reaction occurred with Evodial®. Changes in blood cell concentrations and triglycerides differed between the modes. DISCUSSION: If intermittent haemodialysis is necessary in patients at risk of bleeding, anticoagulation using HAC and Evodial® appeared most preferable with least administration of heparin, lowest APTT increase and lowest risk for prematurely clotted dialyzers in contrast to the least plausible H mode.

Heparin albumin priming in a clinical setting for hemodialysis patients at risk for bleeding.

INTRODUCTION: Intermittent hemodialysis (IHD) is sometimes necessary in patients with a bleeding risk, i.e., before/after surgery or brain hemorrhage. In such case IHD has to be modified to limit the conventional anticoagulation used to avoid clotting of the extracorporeal circuit (ECC). We evaluated if priming using a heparin and albumin (HA) mixture could minimize the exposure to heparin. METHODS: Retrospective data from 1995 to 2013 were collected from 1408 acute dialysis treatment protocols that included 321 patients. Comparisons were made between IHD patients that had increased risk for bleeding and were treated by standard anticoagulation (Group-S), and patients at increased risk of bleeding (Group-HA). The ECC in Group-HA was primed with a solution of unfractioned heparin (UFH) (5000 Units/L) and albumin (1 g/L) in saline that was discarded after priming. There were 16 different dialyzers in the material. FINDINGS: Comparing Group-S (n = 883) with Group-HA (n = 221), the mean age was 61.6 vs. 62.2 years (P = 0.8), dialysis time was 197 vs. 190 minutes (P = 0.002), and total dose of intravenous anticoagulant/IHD was at median 5000 Units vs. 1200 Units (P = 0.001). Twenty-four percent of patients were treated without any additional heparin. Clotting resulting in interrupted dialysis was similar in both groups (0.8% for Group-S vs. 1.0% for Group-HA, P = 0.8). No secondary bleeding was reported in either group. DISCUSSION: HA priming minimized the risk of clotting and enabled acute IHD in vulnerable patients without increased bleeding, thus allowing completion of IHD to the same extent as for standard HD.

NT-proBNP and troponin T levels differ after haemodialysis with a low versus high flux membrane.

BACKGROUND: Brain natriuretic peptide (BNP), N-terminal-proBNP (NT-proBNP), and high sensitive cardiac troponin T (TnT) are markers that are elevated in chronic kidney disease and correlate with increased risk of mortality. Data are conflicting on the effect of biomarker levels by hemodialysis (HD).Our aim was to clarify to what extent HD with low-flux (LF) versus high-flux (HF) membranes affects the plasma levels of BNP, NT-proBNP, and TnT. METHODS AND MATERIALS: 31 HD patients were included in a crossover design, randomized to start dialysis with a LF-HD or HF-HD dialyzer. Each patient was his/her own control. The dialyses included in the study were the first treatments of two consecutive weeks with each mode of dialysis. Patients normally on hemodiafiltration (HDF) also performed a HDF the third week. Values after HD were corrected for extent of ultrafiltration. RESULTS: During LF-HD the biomarkers NT-proBNP and TnT increased (15 versus 6%, P ≤ .001) while there was a slight decrease in BNP (P<.05). During HF-HD the NT-proBNP, BNP and TnT levels decreased (P ≤ .01 for all). During HDF all three markers decreased (P<.01 for all). The rise in TnT during LF-HD correlated with dialysis vintage (months on HD, r = .407, P = .026), Kt/V-urea (r = .383, P = .037), HD time in hours/treatment (r = .447, P = .013) and inversely with residual urinary output (r = -.495, P = .005). The baseline levels of BNP and NT-proBNP correlated with blood pressure. CONCLUSIONS: Cardiac biomarkers increase slightly during LF-HD. A HF-HD eliminates the biomarkers and can mask increases caused by, e.g., myocardial infarction.

Heparin and albumin as part of the priming solution limits exposure to anticoagulation during hemodialysis: in vitro studies.

BACKGROUND: Hemodialysis patients who are subject to increased risk of hemorrhage may need specific dialysis regimes to avoid bleeding. The aim of this study was to determine in vitro which of various anticoagulation options were most beneficial. MATERIALS AND METHOD: 60 in vitro hemodialyses (HD) were performed in parallel using blood from healthy donors. The dialysis circuits were rinsed with either 1 L of 0.9% NaCl alone (n = 6), or with 1 L saline and the addition of either 5 mL 20% albumin (Alb, n = 6), 5,000 U of heparin (Hep, n = 6), Hep and Alb in combination (HA, n = 30), 20,000 U of Hep and Alb (4H-A, n = 6), and finally Hep and 20 mL 20% albumin (H-4A, n = 6). The blood was recirculated for a maximum of 192 min. Clotting was graded. RESULTS: A 192 min dialysis was completed with all series of HA, 4H-A, and H-4A, all with a slight grade of clotting. In contrast to the above settings (p = 0.002, Fisher's test), a total clotting of the dialysis circuit occurred for all series using the NaCl rinsing alone (median time to stop: 21, range:18-27 min, p = 0.026 compared to the HA setting) and for the Alb rinsing (median 26, range: 19-35 min, p = 0.028). CONCLUSIONS: Priming using HA, Hep, 4H-A, and H-4A reduced clotting and allowed 192 min of HD. Clinical studies need to confirm these data in vivo.

Rinsing the extra corporeal circuit with a heparin and albumin solution reduces the need for systemic anticoagulant in hemodialysis.

BACKGROUND: Systemic anticoagulation during hemodialysis (HD) increases the risk for bleeding complications pre- or post-operatively. Based on the concept of blood-membrane interaction, we developed a heparin-albumin solution to rinse the dialysis circuit before start. The aim of this study was to investigate if this method was a valuable tool for our patients at risk for bleeding complications. MATERIAL AND METHODS: This retrospective, comparative, quality assessment study included 248 HD in 68 patients; Group1: 178 treatments were performed at patients for risk of bleeding using heparin-albumin-priming and Group 2: 70 acute HD were performed on patients without increased risk of bleeding using a bolus of heparin at start and a continuous infusion of heparin. In Group 1 additional heparin was given upon suspicion of progressive clotting. One L saline contained albumin (1 g/l) and heparin (5000 U/l) used for priming. Excess priming solution was removed by filling the circuit with blood at start of treatment. RESULTS: In Group 1, a mean total dose of 2000 U of heparin was given during the HD (18% performed HD without any heparin) and Group 2 used a mean total dose of 5500 U (p<0.001). There was no increased incidence of clotting in Group 1 versus Group 2 compared to standard HD. No bleeding complications were reported during any of the HA-priming treatments. CONCLUSIONS: Heparin-albumin priming resulted in a reduced total dose of heparin. There was no increased clotting and no incidence of bleeding was reported in either group.