A nurse is providing teaching for a client who has a new application of a long leg cast. Which of the following instructions should the nurse include?

A. Use a cotton-tip applicator to relieve itching inside the cast.: Inserting any object into the cast can damage the underlying skin, cause abrasions, or introduce infection. Scratching inside the cast may also compromise cast integrity. B. Report any drainage from the casted leg.: Drainage can indicate bleeding, wound infection, or impaired circulation under the cast, all of which require prompt evaluation. Early reporting helps prevent complications such as compartment syndrome or infection progression. C. Keep the casted leg flat for the first 24 hr.: Elevation, not a flat position, is recommended in the first 24 to 48 hours to minimize swelling and pain. Keeping the leg flat can increase edema, which may impair circulation and delay healing. D. Apply a heating pad to the casted leg.: External heat should be avoided because it can cause burns under the cast where the skin cannot be directly monitored. Heat also increases blood flow and swelling, which can worsen pain and increase pressure within the cast.