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Lactate

Plasma
Test performed by: LabPLUS Automation

Specimen Collection

 

Sample must be centrifuged within 60 minutes of collection.

Separated fluoride plasma is stable for

DO NOT USE SERUM


Fluoride4 mL Adult Fluoride Blood (Always Required)
Fluoride0.5 mL Paediatric Fluoride Blood

Paediatric Microcollect Capillary Blood Gas

For capillary sample: Collect one heparinised capillary tube.

Mix well. Transport to laboratory without delay.

Capillary samples are very dependent on the quality of specimen collection, including the maintenance of anaerobic conditions during the procedure, to produce reliable results.

Sample must be centrifuged within 60 minutes of collection.


Reference Intervals

Units: mmol/L

Reference interval:

Venous and Arterial: <2.0 mmol/L (at rest)

Cord blood: <6.1 mmol/L

 

Note:

Locally agreed "action limits" have also been set for other hand-held meters for neonates (<3 mmol/L), and for fetal scalp pH during delivery (<4.2 mmol/L) (see Table below). These are alert thresholds and not reference limits.

 

Uncertainty of Measurement:            5%

** For Whole Blood Uncertainty of measurement refer to the Blood Gases page



Turnaround Time: Within 3 hours
Assay Method

Principle: Enzymatic

Reagents: Roche Lactate kit

Analyser: Cobas c702


Diagnostic Use and Interpretation

Lactate concentrations may be increased in:

A. Tissue hypoxia:

  • Anaerobic exercise
  • arterial hypoxia
  • shock
  • cardiac failure
  • vascular occlusion.

    B. Metabolic disorders:

  • Liver disease
  • drugs/toxins (ethanol, methanol, salicylates, phenformin)
  • thiamine deficiency
  • genetic metabolic defects: glucose-6-phosphatase deficiency, pyruvate dehydrogenase deficiency; defects of gluconeogenesis; respiratory chain disorders ("mitochondrial disease").


    NOTE:  Sample collection
    Plasma lactate may be falsely elevated if a tourniquet is used. 


    LACTATE / PYRUVATE RATIO

    REFERENCE INTERVAL: 6 - 26 (mmol lactate/mmol pyruvate)

    The lactate / pyruvate ratio in plasma is a reflection of the intracellular NADH / NAD ratio.  It is of very limited clinical value, except in the diagnosis of specific metabolic disorders in patients with high lactate. An increased ratio is characteristic of tissue hypoxia from any cause, alcohol, and respiratory chain disorders. A normal ratio is can be seen in thiamine deficiency, pyruvate dehydrogenase deficiency, defects of gluconeogenesis, glucose-6-phosphatase deficiency and liver disease.


    See also

  • Pyruvate
  • CSF lactate
  • Hypoglycaemia - investigations

    Refs:

    Debray F-G, Mitchell GA, Allard P et al. Diagnostic accuracy of blood lactate-to-pyruvate molar ratio in the differential diagnosis of congenital lactic acidosis. Clin. Chem. 2007;53(5): 916-21)


    • Contact Information

    The chemical pathology  team can be reached via email: chemicalpathologist@adhb.govt.nz or via Lablink  (09) 307 4949 ext 22000 or 09-3078995

    Emails will receive priority attention from the on-call chemical pathologist. Include the patients NHI.

    After-hours: contact  Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours .



    Specimen Transport Instructions for Referring Laboratories

    Lactate/pyruvate ratio:

    Test is available only for samples collected at Auckland Hospital.



    Last updated at 11:42:03 16/01/2026