Urgent reversal of vitamin K antagonist therapy

Abstract

In the developed world, an increasing number of patients receive therapy with vitamin K antagonists (VKA). This group of patients poses an additional challenge in the perioperative management of emergency surgery and trauma. The present review offers a detailed description of some treatment options for reversal of VKA therapy. Optimal treatment of the anticoagulated patient requires a well-balanced intervention securing a reduced risk of haemorrhagic surgical complications as well as optimal anticoagulation post-operatively without exposing the patient to an increased risk of thromboembolic complications. The following factors must be considered in VKA-treated patients scheduled for emergency surgery: (1) the indication for VKA therapy, including the risk of thromboembolic events when the International normalized ratio (INR) is reduced, (2) type of surgery, including the risk of haemorrhagic complications and (3) the pharmacodynamic/-kinetic profile of the therapy used to revert the VKA therapy. Therapeutic options for acute reversal of VKA therapy include: vitamin K, fresh frozen plasma (FFP), prothrombin complex concentrate (PCC) and perhaps activated recombinant factor VII. PCC is a relatively new drug in some European countries and clinical experience is limited compared with the use of FFP. Reversal of VKA anticoagulation with PCC is faster and more efficient compared with FFP, but there are currently no randomized studies demonstrating an improved clinical outcome.

Clinical review: Traumatic brain injury in patients receiving antiplatelet medication

“…Anticoagulation with vitamin K antagonists, such as warfarin, has been associated with a high frequency of isolated head trauma, and a high risk of death [3,4]. Although controlled trials have not been carried out for TBI, antagonization of pre-injury vitamin K antagonist effects is possible through application of vitamin K, fresh frozen plasma or prothrombin complex concentrate [5]. Especially administration of prothrombin complex concentrate allows the rapid reversal of anticoagulatory effects of vitamin K antagonists such as warfarin in patients with traumatic haemorrhage [6].…”

Current Anticoagulation Drugs and Mechanisms of Action

“…• Half-life: 1-2 days for warfarin [ 6 ] • Metabolism: CYP2C9 is the most important liver enzyme in metabolizing warfarin [ 7 , 8 ].…”

Stent thrombosis after vitamin K administration

“…Vitamin K can be administered intravenously or orally while subcutaneous administration is not recommended because of the unpredictable and delayed response [4].…”