Final answer:
A weight gain of 3 pounds over 48 hours in a patient with acute kidney injury suggests the nursing diagnosis of Excess Fluid Volume, indicating the kidneys are unable to filter waste and excess fluid is accumulating.
Step-by-step explanation:
A patient being treated for acute kidney injury (AKI) has experienced a weight gain of 3 pounds over the past 48 hours. This assessment finding suggests the nursing diagnosis of Excess Fluid Volume. This diagnosis is made based on the understanding that in AKI, the kidneys are not able to properly filter out waste, which can lead to accumulation of fluid within the body, manifesting as weight gain. It is essential to monitor the patient's fluid balance and adjust treatment as necessary to manage the excess fluid volume.