2 Assessment and Laboratory Findings in Acute Kidney Injury Free Online FlashCards

Why compare kidney-function results with a known baseline?

Compare trends in serum creatinine and measured urine output with a known baseline when possible; a single creatinine value may not show an acute change.

What creatinine rise within $48$ hours meets an AKI criterion?

A rise of at least $0.3\,\text{mg/dL}$ \(26.5\,\mu\text{mol/L}) within $48$ hours meets an AKI criterion and is a Stage 1 creatinine criterion.

How is the KDIGO AKI stage selected when criteria differ?

Use the most severe qualifying serum-creatinine or urine-output criterion. The two measures can identify different patients.

Why can falling urine output warn of AKI before creatinine rises?

Falling urine output can be an earlier warning because creatinine may rise only after kidney function has already declined.

When is estimated glomerular filtration rate less reliable in AKI?

Estimated glomerular filtration rate is less reliable while creatinine is changing rapidly.

What laboratory changes may accompany declining kidney filtration?

Creatinine and blood urea nitrogen commonly rise. Possible complications include hyperkalemia, metabolic acidosis, phosphate retention, and low calcium; these are not automatic features of every stage.

What can urine microscopy suggest about the site of kidney injury?

Granular casts and tubular cells may support tubular injury; red-cell casts or blood with protein may suggest glomerular disease.

Does a bland urinalysis rule out AKI?

No. A bland urinalysis result does not rule out AKI.

Why should urine chemistries not be interpreted alone?

Urine sodium, urea, creatinine, and calculated indices may help distinguish causes in context, but medications and clinical state affect results; do not interpret them alone.

Which assessments can investigate urinary obstruction in AKI?

A bladder scan or postvoid residual can identify retention. Ultrasound is useful when obstruction is suspected or the cause is unclear, but is not routinely required when the cause is established.

What creatinine change over $7$ days meets an AKI criterion?

A rise to at least $1.5$ times baseline within the previous $7$ days meets an AKI criterion.

What urine-output finding meets an AKI criterion?

Urine volume below $0.5\,\text{mL/kg/hour}$ for $6$ hours meets an AKI criterion.