Prolonged immobility during surgery and afterward increases the risk of venous thromboembolism. The potential risk of thrombosis should be assessed.
The need for bridging therapy is very much dependent on the risk of the thrombosis recurring during the period that patients are not receiving anticoagulation therapy. Unfractionated heparin offers some advantages as an anticoagulant in the 24 hours preceding surgery because of its faster onset and offset of action. There is significant disagreement about who should and should not receive such bridging therapy, principally because there is a lack of randomised controlled trial data.
In some situations, clinical experience suggests that bridging anticoagulation is not required. Patients who take anticoagulants because of atrial fibrillation, or in whom the index event requiring anticoagulation occurred more than 3 months ago, can be safely managed without bridging anticoagulation.
These patients are at relatively low risk of thromboembolism. Box 6 lists an appropriate approach for these patients. Patients with prosthetic valves and those who have suffered an acute thrombosis within the preceding 3 months should receive bridging anticoagulation in the perioperative and postoperative period. This should be done in consultation with the relevant experts in this area. Box 6 lists the recommended plan of management for these patients who are at relatively high risk of thromboembolism.
History of gastrointestinal haemorrhage, active peptic ulcer, hepatic insufficiency. Lower the dose or omit the next dose of warfarin. Resume therapy at a lower dose when the INR approaches therapeutic range. Cease warfarin therapy; consider reasons for elevated INR and patient-specific factors. If bleeding risk is high, give vitamin K 1 1. Where there is a low risk of bleeding, cease warfarin therapy, give 2. Any clinically significant bleeding where warfarin-induced coagulopathy is considered a contributing factor.
Cease warfarin therapy, give 5. If fresh frozen plasma is unavailable, cease warfarin therapy, give 5. If Prothrombinex-HT is unavailable, cease warfarin therapy, give 5. See Box 1 for a list of bleeding risk factors. Prepared from plasma collected from voluntary donors. Separated and frozen within 18 hours of collection from volunteer donors.
Contains all coagulation factors. Do not use when coagulopathy can be corrected more effectively with specific therapy, such as vitamin K, cryoprecipitate or other specific factor concentrates.
Each vial also contains 25 IU of antithrombin and IU of heparin. Available in — mL sizes. From relevant blood service or hospital blood bank. No need to consider ABO group.
Predisposition to venous thrombosis, disseminated intravascular coagulation and myocardial infarction. Most common adverse events — allergic reactions and volume overload. Potential for transmission of infections, transfusion-related acute lung injury and other transfusion reactions. If using unfractionated heparin, it should be discontinued 4—6 hours before surgery. Fully anticoagulate the patient with warfarin 72 hours postoperatively as long as there is no evidence of bleeding.
LMWH can accumulate and contribute to bleeding. These consensus guidelines for warfarin reversal were produced by the Warfarin Reversal Consensus Group on behalf of the Australasian Society of Thrombosis and Haemostasis. The guidelines were developed after extensive consultation, including several workshops and teleconferences. The guidelines draw on review of all available evidence from published studies and from clinical experience.
The aim of the Warfarin Reversal Consensus Group is to provide an Australian and New Zealand perspective on the safe and effective management of bleeding risks resulting from warfarin therapy. As part of this grant, a number of members of the WRCG received paid honoraria. Publication of your online response is subject to the Medical Journal of Australia 's editorial discretion. You will be notified by email within five working days should your response be accepted.
Basic Search Advanced search search. Use the Advanced search for more specific terms. Title contains. Body contains. Date range from. Date range to. Article type. Author's surname. First page. Issues by year. Article types. Research letters. Guidelines and statements. Narrative reviews. Ethics and law. Medical education. Position statement. Volume Issue 9. Warfarin reversal: consensus guidelines, on behalf of the Australasian Society of Thrombosis and Haemostasis.
Med J Aust ; 9 : Topics Hematologic diseases. Pharmaceutical preparations. Abstract For most warfarin indications, the target maintenance international normalised ratio INR is 2—3.
Warfarin pharmacokinetics and pharmacodynamics Warfarin and other coumarin anticoagulants act by inhibiting the synthesis of functional vitamin K-dependent coagulation factors II, VII, IX and X. Modifiers of warfarin response Drug interactions can critically interfere with warfarin control.
Bleeding complications of warfarin therapy The most common complication of warfarin therapy is bleeding. General principles for preventing high INR Warfarin is a highly effective medication. Starting warfarin therapy Avoid high loading doses of warfarin, as they are not warranted and may result in bleeding episodes.
Warfarin reversal There is a close relationship between the INR and risk of bleeding. Vitamin K 1 Vitamin K 1 is available as oral tablets or as ampoules for intravenous IV or oral administration. Prothrombin complex concentrate and fresh frozen plasma The full effect of vitamin K 1 in reducing the INR takes up to 24 hours to develop, even when given in larger doses with the intention of complete reversal.
Pre- and postoperative management of anticoagulation Opinion varies about how to manage anticoagulation in patients who have been taking warfarin long-term and who need to undergo surgery, as the evidence is mainly anecdotal.
These include: Prolonged immobility during surgery and afterward increases the risk of venous thromboembolism. INR 5. Any clinically significant bleeding where warfarin-induced coagulopathy is considered a contributing factor Cease warfarin therapy, give 5. Contraindications Patients showing signs of thrombosis or disseminated intravascular coagulation.
Availability From relevant blood service or hospital blood bank. Considerations for use Known allergies to prothrombin complex concentrates. Withhold warfarin therapy 4—5 days before surgery. After surgery Start warfarin therapy on the day of surgery, at the previous maintenance dose.
Employ thromboprophylaxis as per usual practice. Recommence warfarin therapy as soon as possible. Start heparin or LMWH 12—24 hours postoperatively. If using LMWH, give a thromboprophylactic dose. If using unfractionated heparin, aim to prolong the APTT by 1. Background and evidence basis of recommendations These consensus guidelines for warfarin reversal were produced by the Warfarin Reversal Consensus Group on behalf of the Australasian Society of Thrombosis and Haemostasis.
View this article on Wiley Online Library. Hemorrhagic complications of anticoagulant therapy. Chest ; SS. Consensus guidelines for warfarin therapy. Med J Aust ; Australian pharmaceutical index. Boots Healthcare Australia. Australian product information. Anticoagulant thrombolytic, and antiplatelet drugs. New York: McGraw-Hill, Oral anticoagulants: mechanism of action, clinical effectiveness, and optimal therapeutic range.
Chest ; 8SS. Comparison of 5 mg and 10 mg loading doses in initiation of warfarin therapy. Ann Intern Med ; Fugh-Berman A. Herb-drug interactions. Lancet ; Circulation ; Managing warfarin therapy in the community. Aust Prescriber ; A randomised trial of anticoagulants versus aspirin after cerebral ischemia of presumed arterial origin.
Ann Neurol ; Bleeding risks of antithrombotic therapy. BMJ ; Landefeld S, Beyth RJ. Anticoagulant-related bleeding: clinical epidemiology, prediction and prevention.
Am J Med ; Bleeding complications in oral anticoagulant therapy: an analysis of risk factors. Arch Intern Med ; Hemorrhagic complications of anticoagulant treatment. Institute for Clinical Systems Improvement. Health Care Guideline Supplement. Anticoagulation therapy supplement Available at: www. Comparison of mg and 5-mg warfarin initiation nomograms together with low-molecular-weight-heparin for outpatient treatment of acute venous thromboembolism.
Tait RC, Sefcick A. A warfarin induction regimen for out-patient anticoagulation in patients with atrial fibrillation. Br J Haematol ; A randomized trial comparing 5-mg and mg warfarin loading doses. Antithrombotic therapy in patients with mechanical and biological prosthetic heart valves. Chest ; The optimal intensity of vitamin K antagonists in patients with mechanical heart valves: a meta-analysis. J Am Coll Cardiol ; Comparison of low-intensity warfarin therapy with conventional-intensity warfarin therapy for long-term prevention of recurrent venous thromboembolism.
You must also give vitamin K to maintain the reversal of Warfarin. However, vitamin K takes several hours to work up to hours to take full effect as it allows new factors to be made by the liver that's why they're called vitamin K dependent factors.
The main advantage of Bebulin compared to FFP is that much smaller volumes of administration are needed. Bebulin is around cc. People consistently underdose FFP. Sometimes, even as many as 10 units of FFP may be necessary. Keep in mind, that FFP, unlike 0.
So giving 4 units of FFP is the equivalent intravascular volume of giving at least 3L of 0. It has been also been shown to decrease the rate and final size of hematoma expansion in an intracranial hemorrhage compared to FFP. That said, we hope that PCCs can help patients and we know that it can reverse INR faster in life-threatening situations.
Lastly, remember that PCC is concentrated clotting factors. So you can imagine that it would carry some risk of doing more than just reverse anti-coagulation, but actually cause a clot. The incidence of thromboembolic events with 3 factor PCC is around 0. And Vitamin K mg IV for long term reversal. Ask pharmacy for help. While PCCs have never been found to help patients compared to FFP, the standard of care these days in serious life-threatening bleeding including any intracranial bleed is to give PCC if readily available.
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