Clinical QuickieRenal/Electrolytes
Dehydration / Volume Depletion
Volume depletion is a clinical diagnosis supported by data — not a BUN/creatinine ratio.
Build the loss history
Poor intake, vomiting, diarrhea, fever, bleeding, osmotic losses, and diuretics are common pathways.
Use multiple physiologic clues
Orthostasis, tachycardia, hypotension, weight change, urine output, mucous membranes, kidney trajectory, and medication context are more useful together than one lab.
Edema does not exclude low effective circulating volume
Heart failure, cirrhosis, and hypoalbuminemic states can produce peripheral edema while renal perfusion is still reduced.
Reassess after intervention
Symptoms, BP, heart rate, urine output, creatinine, and congestion should move in the expected direction if volume depletion was the dominant mechanism.
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