A client had a mitral valve replacement three days ago. It is MOST important for the nurse to take which of the following actions?
1. Maintain the client in the supine position to prevent tension on the mediastinal suture line.
2. Encourage deep breathing but discourage coughing because of increased central venous pressure.
3. Decrease fluids to prevent fluid retention and development of congestive heart failure.
4. Encourage early activity to promote ventilation and improve quality of circulation.