LACTIC ACID (LACTATE)
Preferred specimen – flouride, gray top. (Alternate: EDTA/Purple top or Lithium Heparin Green Top) Separate the plasma by centrifugation within 30 minutes. (A delay in separation can lead to an increase in lactate values) Transfer plasma to screw-capped plastic vial and freeze immediately; please indicate tube type on transport vial. Contact lab for dry ice for shipment of sample the next day.
Alternate specimen types: EDTA/Lav Top or Lithium Heparin Green top.
Plasma lactic acid concentrations are dependent on the rate of production and the rate of metabolism in the liver and the kidneys. Approximately 30% is used by the liver, predominantly in gluconeogenesis. Lactate concentrations exceeding 5 mmol/L and pH less than 7.25 indicates significant lactic acidosis. Lactate acidosis may occur in shock, hypovolemia, and left ventricular failure or may be metabolic, associated with disease such as diabetes mellitus, neoplasia, liver disease, and drugs/toxins (ethanol, methanol, salicylates).