A nurse is caring for a client who has cirrhosis and a prothrombin time of 30 seconds. Which of the following medications should the nurse plan to administer?

A. Warfarin: Warfarin is an anticoagulant that works by inhibiting the synthesis of vitamin K-dependent clotting factors. In clients with cirrhosis, the liver is already compromised in producing these clotting factors, and further use of warfarin may increase the risk of bleeding. B. Ferrous sulfate: Ferrous sulfate is used to treat iron deficiency anemia and does not address issues related to clotting time or prothrombin time. It is not related to the management of clotting disorders in cirrhosis. C. Heparin: Heparin is an anticoagulant that inhibits clot formation and could increase the risk of bleeding, especially in clients with a prolonged prothrombin time. It is not appropriate for this client with cirrhosis and a prolonged prothrombin time. D. Vitamin K: Vitamin K is crucial for the synthesis of clotting factors, and a prothrombin time of 30 seconds suggests impaired clotting ability, which is common in liver disease. Administering vitamin K helps to reverse the prolonged prothrombin time and improve clotting function.