Final answer:
The major concern of the nurse regarding this patient's care is electrolyte and fluid imbalance.
Step-by-step explanation:
The major concern of the nurse regarding this patient's care is electrolyte and fluid imbalance. Acute kidney injury (AKI) affects the kidneys' ability to regulate electrolyte and fluid levels in the body, leading to potential imbalances. This can have serious consequences for the patient's overall health and well-being.