Cataracts Treatment

My dad is 78 and was scheduled for cataract surgery last week. He has been extremely apprehensive about it for 3 months now. Even though he was nervous he showed up for the surgery. His heart rate went to 135 and the ophthalmologist called the cardiologist and they admitted him to the hospital and now the Dr. wrote a prescription for coumadin. This has him even more upset. Plus the cataract surgery was not done. All the blood work came back normal. It seems like a clear case of anxiety to me. What can he take before the cataract surgery so it does not happen again?