A nurse is providing discharge instructions to a client who has a new prescription for warfarin. Which of the following foods should the nurse advise the client to limit in their diet?

A) Correct. The nurse should advise the client to limit spinach in their diet as this food is high in vitamin K, which can antagonize the anticoagulant effect of warfarin and increase the risk of thrombosis.

B) Incorrect. The nurse should not advise the client to limit bananas in their diet as this food is high in potassium, which can help prevent hypokalemia that can occur with some anticoagulants such as heparin. Bananas do not affect the action of warfarin.

C) Incorrect. The nurse should not advise the client to limit cheese in their diet as this food is high in calcium, which can help prevent osteoporosis that can occur with long-term use of warfarin. Cheese does not affect the action of warfarin.

D) Incorrect. The nurse should not advise the client to limit eggs in their diet as this food is high in protein, which can help maintain muscle mass and wound healing that can be impaired by warfarin. Eggs do not affect the action of warfarin.

B) Correct. The nurse should instruct the client to hold their metformin for 48 hours before and after surgery as this drug can increase the risk of lactic acidosis in clients who are undergoing procedures that involve contrast media or who have impaired renal function due to dehydration or hypotension.

A) Incorrect. The nurse should not instruct the client to take their morning dose of metformin with a sip of water on the day of surgery as this can cause hypoglycemia during anesthesia or interfere with contrast media if used during surgery.

C) Incorrect. The nurse should not instruct the client to resume their metformin as soon as they can tolerate oral intake after surgery as this can cause lactic acidosis if the client's renal function is not fully restored or if they receive contrast media during surgery or postoperatively.

D) Incorrect. The nurse should not instruct the client to switch to insulin injections until they recover from surgery as this can cause hyperglycemia or hypoglycemia depending on the type and dose of insulin used and the client's nutritional status and blood glucose levels.