Creatinine Clearance

Creatinine Clearance

Mnemonic

LAB818
CRCL

Result Availabilty

Within 24 hours

Container

Blood: Gold top (SST) plus
Timed Urine: 24-hour Urine Container, no preservative

Volume

Pref. Vol.: 1.0 mL serum and entire timed urine collection
Min. Vol.: 0.5 mL serum and entire timed urine collection

Collection Instructions

Blood:
• Specimen collected within 72 hours of urine collection period is acceptable
• Routine venipuncture
• Immediately after collection, gently invert tube 5-10 times
• Clot 30 minutes
• Promptly centrifuge 15 minutes
• Refrigerate

Urine:
• To begin collection of timed specimen, have patient urinate noting the date and exact time
• Discard this first portion of urine, but document date and time of voiding on the container label and test requisition as the "start" of the timed specimen
• Save all urine voided during the designated time period (usually 24 hours), including the portion voided at exact end of time period
• Document date and time of final voiding on the label and requisition as the "end" of the timed specimen
• Document patient's weight and height on requisition

24 Hour Urine Collection Instructions

Transportation Instructions

Blood:
• Refrigerated
Time Urine:
• Refrigerate during and after collection

Causes for Rejection

Only one specimen type received (urine or blood, not both)

Remarks

Patient Preparation:
• On day of test, patient permitted to eat moderate breakfast without coffee or tea
• Since patient should be well hydrated before the test start, other non-caffeine fluids are to be encouraged
• Patient should avoid any vigorous exercise

CPT Codes

82575

Effective/Revised

10/10/12