Effect of Injuries in patients receiving warfarin

Injuries in patients who are on oral anticoagulants and antiplatelet drugs

In the recent past increasing number of cardiovascular patients (atrial fibrillation, DVT, post interventions) are put on oral anticoagulants and antiplatelet drugs after a life or limb threatening cardiovascular event.  Therapeutic advancements are increasing probably the need for these special classes of drugs in our patients. We are concerned about the risk of bleeding in such patients.  Spontaneous bleeding is one and prolonged and profuse bleeding from trauma is the other which we may have address in some of these patients. We have already noted the increased risk of puncture site complications (bleeding, pseudo-aneurysm) after angiogram or angioplasty in those receiving the triple antiplatelet therapy in the cardiac patients.  The patients are leading active lives and traveling like any person after recovering from cardiovascular events and there is a probability that they may be prone for injuries. 

If a patient who is on oral anticoagulants or antiplatelet drugs sustain injuries there can be more bleeding and some times it can be life threatening. Bleeding in to the closed cavities such as intracranial, intra thoracic and retroperitoneal can continue for longer periods under the influence of the drugs.  Recently DJ Bonville et al from Albany retrospectively reviewed (3,436) the impact of pre-injury warfarin and antiplatelet drugs (456) on the outcomes of trauma patients from 2004 – 2007 at a New York state level-1 trauma center.   Patients on Warfarin were 3.1 times more likely die after adjusting for potential confounders. Aspirin and clopidogrel were not associated with increased mortality. But these drugs were associated with increased risk of Intra cranial hemorrhage (ICH).   But among the ICH patients increased mortality was associated with warfarin. (Surgery 2011;150: 861-8)

In many countries and in India the aging population is going increase in the coming years. In USA people above 65 years are 13% and they are going to become 20%  in 2050. Some of these are going to receive these medications.  Many studies in the past linked the mortality and morbidity of trauma patients to the use of anticoagulants. In one retrospective study Dossett  et al reviewed one million trauma patients admitted in 402 centers. In this group 36,270 patients were taking warfarin.  Among these taking warfarin 9.3% died and only 4.3% died in the group not taking warfarin. (Arch Surg 2011;146:565-70).

Initiation of oral anticoagulation after giving heparin for 5 days in DVT patients is practiced in many hospitals. The tablet warfarin action is monitored by testing the INR frequently and maintained between 2-3. It is difficult for the patients who are not living close to the towns to get the reliable INR tests. The Indian diet may be also interfering with action of the drugs. Anticoagulation clinics are not present in states like Andhra Pradesh in India. There is a need for the development of web sites to guide these patients about the drug interactions and precautions to be taken while taking the medication. It will be very convenient for the patients if is possible to provide the free testing facilities at the pharmacies supplying (selling) the medications. These patients can carry a card which can be flashed in case of emergency such as trauma to help the treating doctors to take necessary precautions and reverse the effects of anticoagulation (warfarin effect). Correction with Fresh frozen plasma, Injection Vitamin K  and Factor VIIa are used for reversing the warfarin effect.