DEAR FREIND the use of levetiracetam following a surgical intervention on the brain is to prevent seizures if at all they happen. the sub dural hematoma is not actually an issue in brain tissue but between the lining of the brain. it is most unlikely to cause any seizure following inter vention so this rapid rate of reduction in dosage is not unsafe. the haematoma may have happened due to the anticoagulants he has been taking for his A fib and followed by tricuspid repair Coumadin or Warfarin is commonly called a blood thinner, but the more correct term is anticoagulant. It helps to keep blood flowing smoothly in your body by decreasing the amount of certain substances (clotting proteins) in your blood. while aspirin prevents clot formation by inhibiting the platelets from aggregating and forming a clot. both if taken together at times may cause bleeding spontaneously. to titrate the dosage of coumadin your husband should have been advised to keep a parameter called PT INR in a certain range which indicates towards adequacy of reduction in clotting risk vis a vis risk of bleeding. you need to discuss the further course of action with your treating physician. if the question was only about Keppra i think i have provided the answer but the second part of the question does not ask a query hence the explanation and the suggestion