The Clinical Guide “A Guide to Implementing Renal Best Practice in Haemodialysis“ Chapter 5: Anticoagulation Team Leader: Angela Henson Co-authors: Franta Lopot Presented by Dr.James Tattersall

What does the chapter include?  Seven sections  45 practice suggestions with rationale  Diagrams demonstrating clotting mechanism and blood circuit  Chart to assist visual scoring of dialyser clotting  27 references

Aim of chapter: Assist nurses involved in the dialysis treatment to:  Individually assess patients risk factors in regards to coagulation and bleeding  Determine when variations are required in anticoagulation treatment regimes  Understand the various methods and medications available to review/prevent coagulation of the dialysis circuit

Introduction: clotting mechanism

Introduction: Factors which increase risk of clotting  Platelet infusion  High ultrafiltration rate  High haematocrit  Intra-dialytic hypotension  Air in circuit  Low blood flow  Long treatment time  High dialyser priming volume

Types of anticoagulant  Unfractionated heparin  Low molecular weight heparin  Glycosaminoglycans  Regional citrate  No anticoagulant

5.1 Before administering anticoagulant  Changes in clinical condition may require change in anticoagulant type (e.g. Recent surgery,liver failure)  Other medications may impact on metabolism of anticoagulant, requiring dose change  Is the patient already taking an anticoagulant or anti-platelet drug  Changes in dialysis modality (e.g. HDF), UF rate, dialysis time or blood flow may require changes in anticoagulant dose or regime

5.1 Nurses need to be aware of:  Duration of action of anticoagulant  Drugs which may interact with anticoagulant  Risks and adverse effects of anticoagulants  How to administer an antidote to the anticoagulant (if available)  If possible, connect and monitor the pressure between blood pump and dialyser (the most sensitive way to detect early clotting)

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5.2 Machine preparation, anticoagulant administration and monitoring  Blood and dialysate pathway must be primed to remove all of air before starting dialysis  Do not use heparin in prime solution  Use correct syringe type for anticoagulant infusion  Establish baseline clotting time (if appropriate)  Use venous sample port for blood samples to monitor clotting during dialysis  Visually inspect circuit and dialyser for clotting, especially in high risk patient  Do not wash back when circuit is clotted  Score dialyser clotting after dialysis

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5.3 Anticoagulation with UnFractionated Heparin (UFH)  Deliver as initial bolus followed by continuous infusion  Infusion delivered by pump integrated into dialysis machine  In high bleeding risk, infusion is omitted or rate reduced  Time infusion is stopped before end of dialysis individualized according to bleeding risk  Monitor anticoagulant effect using APPT (laboratory) or ACT (bedside test)  Nurses need to be aware of potential adverse effects (e.g. Heparin Induced Thrombocytaemia)  Nurses need to be aware of factors causing anticoagulant resistance and discuss any patient requiring high heparin doses

5.4 Anticoagulation with low-molecular weight heparin (LMWH)  Deliver as bolus into venous port at start of dialysis (no infusion)  LMWH doses are calculated on patients ideal body weight and doses need to be verified prior to administration.In high bleeding risk, infusion is omitted or rate reduced  Monitoring of anticoagulant effect not required for LMWH  Nurses need to be aware of potential adverse effects

5.5 Anticoagulation with other anticoagulants  Other agents such as glycosaminoglycans may be utilised due to its binding interaction with heparin cofactor II (HCII) and resultant regulation of coagulation.  Glycosaminoglycans are given as a bolus and maintenance dose via an infusion pump.  Monitoring possibilities include review of the dialysis circuit and utilisation of coagulation studies as recommended by the Physician.

5.6 Regional anticoagulation - citrate/calcium gluconate  Appropriate staff training, equipment, monitoring strategies and protocols are required.  Protocols need to be specific in regards to administration rates of citrate anticoagulant infused into arterial line whilst calcium chloride is infused into the venous line.  It is recommended that the calcium replacement is administered via a separate infusion pump.  Careful monitoring of calcium levels is recommended during and on completion of treatment.  Regional citrate anticoagulation is not suitable for patients with severe liver failure due to increased risks.  Heparin/protamine regional anticoagulation is not recommended.

5.7 Sustaining treatment without anticoagulation  Saline flushes ml every 30-60minutes. Caution, may increase clotting by diluting natural anticoagulants in stable patients  Consider wash back and change circuit in middle of treatment  Consider pre-dilution HDF  If clotting suspected during treatment, consider small dose of anticoagulant (if early in treatment) or early termination (if late in treatment)  Citrate-based ‘A’ concentrate should be considered to reduce clotting risk and requirement for anticoagulant  Precautions are advised when administering packed cell transfusions to minimise risk of clotting within the circuit