Traumatic head injury in the anticoagulated elderly patient: A lethal combination

Warfarin is the most common oral anticoagulant used for chronic anticoagula tion therapy. Even without any antecedent trauma overanticoagulation can re sult in intracranial hemorrhage. The triad of anticoagulation with warfarin , age greater than 65 years, and traumatic head injury frequently produces a lethal brain hemorrhage. A retrospective review of more than 2000 patient s admitted to the Trauma Service between September 1998 and May 2000 produc ed 278 patients with head injury and CT-documented intracranial hemorrhage. Of these patients 21 were admitted with an elevated prothrombin time (PT) due to anticoagulation with warfarin. Eighteen patients (86%) were above th e age of 70. The most common indications for anticoagulation were atrial fi brillation (71%), deep venous thrombosis (19%), aortic valve replacement (9 %), and ischemic cerebral infarcts (9%). Fourteen injuries were the result of a fall, one resulted from a gunshot wound, and one resulted from an assa ult. The remaining five patients were excluded as their history, workup, an d evaluation by neurosurgery suggested a spontaneous bleed leading to fall rather than a fall causing a traumatic bleed. The average Glasgow Coma Scor e on admission was 11. The average PT and International Normalized Ratio (I NR) on admission were 19.2 and 2.99 respectively. Eight of the 16 patients analyzed died. The risk of intracranial hemorrhage with relatively minor he ad injury is increased dramatically in the anticoagulated patient. A mortal ity rate of 50 per cent far exceeds the mortality rate in patients with sim ilar head injuries who are not anticoagulated. In addition the risk/benefit equation of anticoagulation for the elderly is more complex and differs fr om that for younger patients. Perhaps more frequent and judicious monitorin g of prothrombin time levels with lower therapeutic ranges (INR 1.5-2) is n ecessary.