The LPN is preparing to ambulate a client post total knee replacement. Which of the following actions should the nurse perform prior to ambulating the client?

The correct action to perform before ambulating a client post total knee replacement is to assist the client to a sitting position at the edge of the bed. This step is crucial to prevent orthostatic hypotension and ensure the client is ready to stand and walk safely. Having the client march in place or raise his arms above his head are not necessary preparations for ambulation. While knowing about the client's fall history is important for safety reasons, it is not the priority action immediately before ambulating the client.