In which situation would a nurse be concerned about a potential for acute kidney injury?

A nurse would be concerned about acute kidney injury when assessing a patient who has a urine output of 100 mL on day two post-surgery. This is particularly significant because normal urine output is generally considered to be around 30 mL per hour, translating to at least 720 mL over a 24-hour period. A urine output of only 100 mL over the course of two days indicates severely reduced kidney function and can be a sign of acute kidney injury.

This situation requires immediate attention, as poor urine output can lead to fluid overload, electrolyte imbalances, and potentially life-threatening complications. The reduction in urine volume indicates that the kidneys may not be filtering wastes effectively, which is critical to monitor during the postoperative period when patients are at increased risk for various complications, including renal dysfunction.

In contrast, the other scenarios do not necessarily present as immediate red flags for kidney injury. For instance, the presence of crackles could indicate fluid overload but does not directly implicate the kidneys. Increased pain may be a normal postoperative occurrence and not indicative of renal function. Normal vital signs on day one suggest the patient is stable, which does not inherently signal kidney concerns. Thus, urine output remains the most direct and concerning measure in assessing