UREA NITROGEN, URINE 24HR
24 hour urine collection preferred. Refrigerate during collection. Record total volume on aliquot of urine and lab order.
Random urine is also acceptable; submitted in sterile screw-capped container.
7 days refrigerated
Renal function test; coarse nitrogen-wasting test on patients on hyperalimentation; indicate nitrogen balance in hyperalimentation; rule out tap of urinary bladder in amniocentesis, paracentesis