A nurse is planning care for a client who is 6 hr postoperative following a right knee arthroplasty. Which of the following interventions should the nurse include in the client's plan of care?

A. Massage the lower leg in smooth, long strokes: Massaging the lower leg after knee arthroplasty increases the risk of dislodging a thrombus, especially in the early postoperative period when the client is at high risk for deep vein thrombosis. Mechanical manipulation of the limb should be avoided to reduce embolic risk. B. Place a pillow under the client's surgical knee: Placing a pillow under the knee promotes flexion and can lead to joint contractures. After knee arthroplasty, the knee should be kept in extension to support proper alignment and prevent stiffness. A pillow may be placed under the calf instead if elevation is needed. C. Use the continuous passive-motion machine intermittently: Continuous passive-motion machines are used early after knee arthroplasty to improve joint mobility, reduce stiffness, and promote circulation. Intermittent use as prescribed helps maintain range of motion without overfatiguing the joint. This intervention supports functional recovery and rehabilitation. D. Apply warm, moist packs to the surgical site: Warm packs increase blood flow and may worsen postoperative swelling or bleeding at the surgical site. Cold therapy is preferred in the immediate postoperative period to reduce inflammation, pain, and edema. Warm applications are not appropriate at this stage of recovery.