Practical haemodialysis began with cellophane and heparin: the crucial role of William Thalhimer (1884-1961)

Lipid and Bone Effects of Heparin Use During Hemodialysis

Unfractionated heparin (UFH) and low-molecular-weight heparins (LMWHs) are commonly prescribed anticoagulants for chronic hemodialysis (HD). The dialysis population comprises a unique group that receives heparin three times per week for a long period, with potential long-term cumulative metabolic effects such as osteoporosis and worsening lipid profile. HD patients have approximately half the number of lipases as healthy individuals, and their lipid metabolism is limited because of this decrease as well as partially inhibited function. Administration of UFH or LMWHs for anticoagulation can lead to metabolic starvation despite high triglyceride levels at the end of HD. In vitro studies indicate that UFH and LMWHs inhibit osteoblasts and promote osteoclasts. In patients on HD, long-term use of UFH or LMWHs did not worsen chronic kidney disease-mineral bone disease. Further investigation is needed to elucidate the underlining mechanisms of UFH and LMWHs and their possible influences on maintenance HD patients.

Primary Failure of Autogenous Arteriovenous Fistula: Critical Analysis

Introduction:

Permanent vascular access is an essential intervention in patients with advanced chronic kidney disease (CKD) and its success depends on various non-modifiable and modifiable factors. Considering the element of unpredictability and failure, we attempted to analyze various factors responsible for primary arteriovenous fistula (AVF) failure in presumed high-risk groups.

Materials and Methods:

We conducted an observational study of newly created AVFs at a tertiary referral government hospital in Eastern India between January 2014 and June 2015. All adult CKD patients undergoing AVF creation were included. Primary AVF failure was assessed at 12 weeks and total follow-up was 24 weeks in presumed high-risk groups of females, patients aged ≥65 years and those with diabetes mellitus.

Results:

Female gender was at a higher risk of primary AVF failure if aged ≥65 years (P = 0.0026), second AVF creation (P = 0.03), loupe magnification not used (P = 0.03), arterial plaque (P = 0.028), absent immediate thrill, and with radiocephalic AVF (P = 0.02). Absent immediate thrill (<0.0001) and AVF size ≤5 mm (P = 0.002) were important independent risk factors for primary failure. Diabetes or elderly age did not have additional risk, except with uncontrolled hypertension and female gender.

Conclusion:

Female gender was at a higher risk of poor unassisted AVF patency if their age was ≥65 years, had second AVF creation, loupe magnification not used or if arterial plaque was present. An absence of thrill immediately or at 24 hours or an AVF diameter ≤5 mm were independent intraoperative factors for poor outcome. On the contrary, diabetics, elderly males and intimal thickness were essentially noncontributors for AVF failure, except in few subsets.

Anticoagulation in hemodialysis: A narrative review

Systemic anticoagulation in maintenance hemodialysis (HD) has historically been considered necessary to maintain the extracorporeal circuit (ECC) and preserve dialysis efficiency. Unfractionated heparin (UFH) is the most commonly used anticoagulant due to low cost and staff familiarity. Despite widespread use, there is little standardization of heparin dosing protocols in the United States. Although the complication rates with UFH are low for the general population, certain contraindications have led to exploration in alternative anticoagulants in patients with end-stage kidney disease (ESKD). Here we review the current evidence regarding heparin dosing protocols, complications associated with heparin use, and discuss alternatives to UFH including anticoagulant-free routine HD.

Gene co-expression network analysis identifies the hub genes associated with immune functions for nocturnal hemodialysis in patients with end-stage renal disease

End-stage renal disease (ESRD) is the final stage of chronic kidney disease in which the kidney is not sufficient to meet the needs of daily life. It is necessary to understand the role of genes expression involved in ESRD patient responses to nocturnal hemodialysis (NHD) and to improve the immunity responsiveness. The aim of this study was to investigate novel immune-associated genes that may play important roles in patients with ESRD.The microarray expression profiles of peripheral blood in patients with ESRD before and after NHD were analyzed by network-based approaches, and then using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway analysis to explore the biological process and molecular functions of differentially expressed genes. Subsequently, a transcriptional regulatory network of the core genes and the connected transcriptional regulators was constructed. We found that NHD had a significant effect on neutrophil activation and immune response in patients with ESRD.In addition, Our findings suggest that MAPKAPK3, RHOA, ARRB2, FLOT1, MYH9, PRKCD, RHOG, PTPN6, MAPK3, CNPY3, PI3KCG, and PYGL genes maybe potential targets regulated by core transcriptional factors, including ARNT, C/EBPalpha, CEBPA, CREB1, PSG1, DAND5, SP1, GATA1, MYC, EGR2, and EGR3.

Effects of unfractionated heparin on renal osteodystrophy and vascular calcification in chronic kidney disease rats

Unfractionated heparin (UFH) is the most widely used anticoagulant in hemodialysis for chronic kidney disease (CKD) patients. Many studies have verified that UFH can induce bone loss in subjects with normal bone, but few have focused on its effect on renal osteodystrophy. We therefore investigated this issue in adenine-induced CKD rats. As CKD also impairs mineral metabolism systemically, we also studied the impacts of UFH on serum markers of CKD-mineral and bone disorder (CKD-MBD) and vascular calcification. We administered low and high doses of UFH (1U/g and 2U/g body weight, respectively) to CKD rats and compared them with CKD controls. At sacrifice, the serum markers of CKD-MBD did not significantly differ among the two UFH CKD groups and the CKD control group. The mean bone mineral densities (BMDs) of the total femur and a region of interest (ROI) constituted of trabecular and cortical bone were lower in the high-dose UFH (H-UFH) CKD group than in the CKD control group (P<0.05 and P<0.01, respectively). The BMD of the femoral ROI constituted of cortical bone did not differ between the H-UFH CKD group and the CKD control group. Histomorphometrical changes in the CKD rats indicated secondary hyperparathyroidism, and the femoral trabecular bone volume, but not cortical bone volume, significantly decreased with increasing UFH dose. The same decreasing trend was found in osteoblast parameters, and an increasing trend was found in osteoclast parameters; however, most differences were not significant. Moreover, no distinct statistical differences were found in the comparison of vascular calcium or phosphorus content among the CKD control group and the two UFH CKD groups. Therefore, we concluded that UFH could induce bone loss in CKD rats with secondary hyperparathyroidism, mainly by reducing the trabecular volume and had little effect on cortical bone volume. The underlying mechanism might involve inhibition of osteoblast activity and promotion of osteoclast activity by UFH. We did not find any effect of UFH on vascular calcification in CKD rats with secondary hyperparathyroidism.

Use and safety of unfractionated heparin for anticoagulation during maintenance hemodialysis

Anticoagulation is essential to hemodialysis, and unfractionated heparin (UFH) is the most commonly used anticoagulant in the United States. However, there is no universally accepted standard for its administration in long-term hemodialysis. Dosage schedules vary and include weight-based protocols and low-dose protocols for those at high risk of bleeding, as well as regional anticoagulation with heparin and heparin-coated dialyzers. Adjustments are based largely on clinical signs of under- and overanticoagulation. Risks of UFH use include bleeding, heparin-induced thrombocytopenia, hypertriglyceridemia, anaphylaxis, and possibly bone mineral disease, hyperkalemia, and catheter-associated sepsis. Alternative anticoagulants include low-molecular-weight heparin, direct thrombin inhibitors, heparinoids, and citrate. Anticoagulant-free hemodialysis and peritoneal dialysis also are potential substitutes. However, some of these alternative treatments are not as available as or are more costly than UFH, are dependent on country and health care system, and present dosing challenges. When properly monitored, UFH is a relatively safe and economical choice for anticoagulation in long-term hemodialysis for most patients.

The wonderful apparatus of John Jacob Abel called the "artificial kidney"

Hemodialysis, which now provides life-saving therapy to millions of individuals, began as an exploratory attempt to sustain the lives of selected patients in the 1950s. That was a century after the formulation of the concept and determination of the laws governing dialysis. The first step in the translation of the laboratory principles of dialysis to living animals was the "vividiffusion" apparatus developed by John Jacob Abel (1859-1938), dubbed the "artificial kidney" in the August 11, 1913 issue of The Times of London reporting the demonstration of vividiffusion by Abel at University College. The detailed article in the January 18, 1914 of the New York Times, reproduced here, is based on the subsequent medical reports published by Abel et al. Tentative attempts of human dialysis in the decade that followed based on the vividiffusion apparatus of Abel and his materials (collodion, hirudin, and glass) met with failure and had to be abandoned. Practical dialysis became possible in the 1940s and thereafter after cellophane, heparin, and teflon became available. Abel worked in an age of great progress and experimental work in the basic sciences that laid the foundations of science-driven medicine. It was a "Heroic Age of Medicine," when medical discoveries and communicating them to the public were assuming increasing importance. This article provides the cultural, social, scientific, and medical background in which Abel worked, developed and reported his wonderful apparatus called the "artificial kidney."

HEMATOLOGY: ISSUES IN THE DIALYSIS PATIENT: The Safety of Heparins in End-Stage Renal Disease

In patients on chronic dialysis, unfractionated heparin (UFH) is the most commonly used agent for anticoagulation of the hemodialysis extracorporeal circuit, for hemodialysis catheter "locking" between dialysis treatments, and for nondialysis indications such as venous thromboembolic disease, peripheral vascular disease, and acute coronary artery disease. Potentially serious complications of UFH, such as hemorrhage, osteoporosis, and thrombocytopenia, have led to consideration of other options for anticoagulation, including low molecular weight heparin (LMWH) and direct thrombin inhibitors (DTIs). LMWH can be used for anticoagulation of the hemodialysis circuit, but whether this has significant benefit compared to UFH remains to be proven. Because of the somewhat unpredictable risk of severe bleeding complications when LMWH is used for other indications in dialysis patients, UFH rather than LMWH is preferred for treatment of thromboembolic disease in these patients. DTIs have been used for anticoagulation in dialysis patients with heparin-induced thrombocytopenia (HIT), with argatroban being the preferred agent if heparin-free hemodialysis cannot be performed. UFH still remains the preferred anticoagulant in the vast majority of dialysis patients requiring systemic anticoagulation and for anticoagulation of the extracorporeal hemodialysis circuit.