Renal & Electrolytes

AKI

• Prerenal: volume depletion, low effective arterial volume; often BUN/Cr >20.
• Intrinsic: ATN, AIN, GN; use urinalysis patterns.
• Postrenal: obstruction; renal ultrasound when suspected.

Hyperkalemia

• ECG changes: calcium first.
• Shift K intracellular: insulin/glucose, albuterol.
• Remove K: diuretics, binders, dialysis.

Hyponatremia

• Severe neuro symptoms: hypertonic saline.
• Avoid overly rapid correction to prevent osmotic demyelination.
• Always consider glucose correction before calling it true hyponatremia.