Final answer:
The statement about taking warfarin needs clarification because it's an anticoagulant that should usually be stopped before surgery to reduce bleeding risk.
Step-by-step explanation:
The client statement that indicates a need for further clarification by the nurse is: "I took my warfarin last night according to my usual schedule." Warfarin is an anticoagulant that can increase bleeding risk during surgery. It is typically stopped several days before surgery to reduce this risk. The nurse needs to clarify this with the client and possibly consult with the physician to confirm if the medication should have been discontinued prior to the coronary artery bypass graft (CABG) surgery.