What it means
creatininekree-AT-uh-neenA waste product of muscle that the kidneys remove from the blood; its blood level is used to measure how well the kidneys work.Full entry is a waste product from muscle that the kidneys filter out. Comparing the creatinine in a 24-hour urine collection with the creatinine in the blood shows how many milliliters of blood the kidneys clean each minute, close to the glomerular filtration rate. It is also estimated from a formula (such as Cockcroft-Gault) using age, weight, sex and serum creatinine, which pharmacists use to adjust drug doses.
For the nurse
For a 24-hour collection, have the client empty the bladder and discard that urine at the start time, then save every drop for 24 hours, ending with a final void at the stop time. Keep the container cold if required. One missed void spoils the test: restart it.
In a chart
"24-hour urine for creatinine clearance started at 0700 after first void discarded."
At a glance
| Normal range | Roughly 90–140 mL/min [1.5–2.3 mL/s] in healthy adults; lower in women and in older adults. |
|---|---|
| Also written | CrCl |
Related terms
chronic kidney disease
Kidney damage or reduced kidney function that lasts longer than three months.
renal
Relating to the kidneys.
creatinine
A waste product of muscle that the kidneys remove from the blood; its blood level is used to measure how well the kidneys work.