Final answer:
The nurse's initial action should be to notify the physician of the change in peripheral perfusion.
Step-by-step explanation:
The nurse's initial action should be to c. notify the physician of the change in peripheral perfusion. The sudden left leg pain with pallor, paresthesia, and loss of peripheral pulses indicate a serious problem with the patient's circulation. The nurse should immediately report these symptoms to the physician to ensure prompt evaluation and intervention.