Final answer:
The first action a nurse should take when ambulating a patient who has been in bed for several days is to dangle the patient at the bedside to allow the body to adjust to a change in position and prevent orthostatic hypotension.
Step-by-step explanation:
When considering the scenario where the patient has been in bed for several days and needs to be ambulated, the first action a nurse should take is b. Dangle the patient at the bedside. This step is crucial as it allows the patient's body to adjust to the change in position and reduces the risk of orthostatic hypotension, a condition characterized by a sudden drop in blood pressure when a person stands up from lying down or sitting. Once the patient stabilizes in this position, further ambulation can be considered.
Other options such as encouraging isometric exercises, suggesting a high-calcium diet, or maintaining a narrow base of support are follow-up or adjunct measures but not initial steps in the ambulation process. Isometric exercises can strengthen muscles without movement, and a high calcium diet can support bone density, but neither addresses the immediate need to acclimate the patient's cardiovascular system to movement. A narrow base of support would actually be less stable and is not recommended when initially getting a patient out of bed after extended rest.