In general, the type of procedure determines the risk of bleeding and how long anticoagulation must be withheld post-operatively.An INR Baseline INR is recommended in every case and this will guide further therapy.Discuss with surgeon and anesthesiologist what the goal INR should be before surgery.Management of Perioperative Anticoagulation Available in large centres rural centres can have FP shipped quickly from nearby larger centres as needed.Indicated for rapid reversal when PCC not available.May be associated with clinically important thrombosis.Contains heparin and is contraindicated in patients with heparin induced thrombocytopenia and liver insufficiency (see product monograph).who require surgery within next 6 hours.Indicated for immediate INR reversal in patients:.Must be used in conjunction with IV vitamin K.Virally inactivated plasma-derived concentrate containing factors II, VII, IX, X and Protein C and Protein S.Duration of action is ~6 hours, typically only one dose is needed.Preferred product for rapid reversal of warfarin when available.Use only in consultation with specialist.Virally Inactivated Plasma-Derived Prothrombin Complex Concentrate IV 5 mg in 50cc normal saline infused over 30 minutes.Effect on INR is observed after 8 - 12 hours, depending on route of administration.Excessive dose of vitamin K can lead to difficulty with re-anticoagulation.Useful for postoperative periods as well.If the procedure is in more than 24 hours, there is no difference between using IV and oral (PO).Intramuscular (IM) or subcutaneous delivery should be avoided.Intravenous (IV) delivery is the fastest and most reliable way to obtain the effect of vitamin K.Management Therapeutic Measures for Reversal of Warfarin Therapy Vitamin K When reversal of anticoagulation is required within 6 hours, intravenous vitamin K and prothrombin complex concentrate (PCC) (e.g., Octaplex ®, Beriplex ®) is highly effective and is recommended over frozen plasma infusion. If urgent or emergent procedures are to be undertaken in < 4-5 days and warfarin reversal is required, it may be satisfactory to give 1-2 mg of vitamin K orally in order to expedite the reversal process. LMWH used postoperatively may allow earlier discharge of the patient compared with using unfractionated heparin. For patients at high risk of thrombosis, LMWH by injection is given concurrently with warfarin and the overlap is maintained until a therapeutic INR has been reached. Restarting warfarin may be delayed in neurosurgical patients, those receiving epidural analgesia and in patients who are bleeding. 3 Typically, warfarin can resume the evening of or next day after the procedure because the anticoagulant activity is not established for several days. Postoperative anticoagulation increases the rate of major bleeding. Postoperative management of warfarin therapy consists of re-initiation of anticoagulation. Patients with a high risk of thromboembolism or stroke may benefit from bridging with heparin during the preoperative period, either as outpatients (LMWH subcutaneously) or inpatients (unfractionated heparin intravenously) by shortening the duration of subtherapeutic anticoagulation. Almost all patients will achieve an international normalized ration (INR) of 70 years) will require a longer period of warfarin withdrawal before surgery. Preoperative management of warfarin therapy consists of timely discontinuation of warfarin and replacement (known as “bridging”) with therapeutic low molecular weight heparin (LMWH) or unfractionated heparin if the risk of thrombosis is considered to be sufficiently high. It is recommended that the anesthesiologist and the surgeon be consulted in determining the hemorrhagic risk. The risk of hemorrhage in the perioperative period depends on the patient’s age, associated medical conditions, type of procedure, approach, site, type of incision and closure, and the method of administration of anesthesia and analgesia. The thrombotic risk in the perioperative period depends on pre-existing conditions, the time since the last episode of thrombosis, and the thrombotic effect of surgery. The management of warfarin therapy in patients undergoing surgery or other invasive procedures involves a fine balance between the risk of hemorrhage if the procedure was performed while on warfarin, and the risk of thrombosis if warfarin was discontinued.

Inr normal range 4