Methodology
Quantitative Enzymatic Assay
Synonyms
Lactate Pyruvate Ratio; LP Ratio; Pyruvate (Pyruvic Acid)
Specimen Type
Whole Blood
Performing Lab
ARUP
Epic ID
Other Reference Test
Lab Test Days
Daily
Standard TAT
1-2 Days
Collection Information
Specimen Required
1 mL Whole Blood
Container Type
Sodium Heparin (Dark Green-Top) Tube
Collection Instructions
Patient should be fasting and at complete rest. Patient should avoid any exercise of the arm or hand before or during collection. Draw the specimen without the use of a tourniquet or within three minutes of applying the tourniquet, but before releasing the tourniquet. Whole blood collected in a lithium heparin (dark green-top) tube is also acceptable. If whole blood is collected in a syringe, transfer immediately to green (sodium or lithium heparin) tube before preparing specimen. Immediately after blood is drawn, add exactly 1 mL whole blood to a chilled pyruvate collection tube containing 2 mL 8 percent (w/v) perchloric acid. Mix well for 30 seconds then place in an ice bath for 10 minutes. Deliver sample on ice to lab.
Processing Information - Lab Use Only
Transport Temperature
Frozen-Only
Specimen Stability
Room Temp: Unacceptable; Refrigerated: 2 Days; Frozen: 4 weeks (preferred)
Test Volume Required
2 mL Supernatant
Minimum Test Volume
1 mL Supernatant
Processing Instructions
Centrifuge for 10 minutes at 1500 x g. Decant 1-2 mL supernatant and freeze immediately. Compete an ARUP requisition and submit with specimen frozen. Send with daily Apollo Courier.
Included Tests
Lactate, Pyruvate and L:P Ration
Comments
If addition to perchloric acid is delayed, lactate concentration of whole blood increases by approximately 30 percent after 30 minutes, 50 percent after 1 hour, and 75 percent after 2 hours at room temperature. If less than 1 mL of blood is added to collection tube, pH of the supernatant will be too low for testing.
CPT Codes
84210, 83605 (not genetic)
Revised
5/14/26
Initials
IM