know that patients dialysing Selleckchem Ceritinib with a venous dialysis catheter are at greater risk of thrombosis. With some trial and error, the right dose of anticoagulant for any patient can be empirically determined. In normal circumstances effective and safe anticoagulation for haemodialysis can be delivered with low risk and high efficiency. The use of UF heparin, which is the most common agent used in Australia, is safe, simple and inexpensive and usually encounters few problems. However, there are risks with haemodialysis anticoagulation which are important to be aware of and which of course include the risk of bleeding. Some risks are not immediately obvious – such as inadvertent over-anticoagulation in high-risk patients because of excessive heparin volume used to lock the venous dialysis catheter at the end of dialysis. The disadvantages of UF heparin may include lack of
routine or accurate monitoring of anticoagulation effect, the need for an infusion pump and the costs of nursing time. Perhaps the most important risk is that of heparin-induced thrombocytopaenia (HIT Type II), which is greatest with the use of UF heparin. At times the routine anticoagulation prescription needs to be varied. Additional choices include ‘no heparin’ dialysis, the use of low-molecular-weight heparin (LMWH) instead buy Sunitinib of UF heparin, and the use of regional anticoagulation. New agents and new clinical variations appear in the literature continuously. Dialysis without anticoagulation may be indicated in patients with a high risk of bleeding, an acute
bleeding disorder, a recent head injury, planned major surgery, trauma, acute HIT syndrome or in patients below with systemic anticoagulation for other reasons. The procedure involves multiple flushes of 25–50 ml of saline every 15–30 min, in association with a high blood flow rate. In some units the lines are pretreated with 2000–5000 U of UF heparin and then flushed with 1 l of normal saline, to coat the lines. This form of dialysis anticoagulation is very labour-intensive and these efforts are usually only partially effective. Partial clotting still occurs in 20% of cases with complete clotting of lines or dialyser, requiring line change, in 7% of ‘no heparin’ dialyses.7,8 The risk of clotting in this setting may be exacerbated by poor access blood flow, the use of a venous catheter, hypotension or concomitant blood transfusion. Where a venous catheter is used, there is an increased risk of catheter occlusion. ‘No heparin’ dialysis may also provide less effective dialysis and result in lower clearances. Unfractionated heparin was first isolated from liver (hepar) mast cells of dogs. UF heparin consists of a family of highly sulphated polysaccharides composed of anionic glycosaminoglycans. Heparin is now commercially derived from porcine intestinal mucosa or bovine lung.