If a nurse discovers that 4 hours of fluid has infused in the past 1 hour during a routine check, what should be the nurse's first action?

When a nurse identifies that a significant amount of fluid has infused over a shorter period than expected, the first action should be to reduce the infusion rate. This response is crucial to prevent potential complications associated with fluid overload, which can lead to serious consequences such as pulmonary edema or heart failure. By adjusting the infusion rate immediately, the nurse can help ensure that the patient receives the correct volume of fluid over the prescribed duration, minimizing the risk of adverse effects.

The recognition of rapid infusion allows the nurse to maintain patient safety as a priority. Notifying the physician may be necessary depending on the circumstances, but immediate intervention to correct the infusion rate is more critical in this scenario. Changing the IV bag or infusing normal saline may not address the underlying issue of over-infusion and could compound the risk of fluid overload in the patient.