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Laboratory Test Reference Guide

Laboratory Information

Test Name

Lactate (Blood Gas)

Specimen Collection

Specimen Collection and Transport Protocols

Remove at least 3 ml of blood to waste prior to collecting the blood sample from a line.  Must be analysed within 15 minutes of collection.


Adult Specimen

1.0 ml blood in an adult blood gas syringe or 0.5 ml in a paediatric blood gas syringe or 45 ul in a plastic capillary tube

Paediatric Specimen

0.5 ml blood in a paediatric blood gas syringe or 45 ul in a plastic capillary tube

Sample Delivery to Lab


Test Information


Biochemistry and POCT

Test Availability

Mon - Sun, 24hrs

Laboratory Turnaround Time

30 minutes


Blood gas analyser

Unit of measurement


Reference interval

Adult 0.6 - 2.4 mmol/L

Cord Blood (arterial & venous) <6.1 mmol/L

Uncertainty of measurement

± 10%

Diagnostic Use Or Instructions

Lactic acidosis is considered to be present when lactate is elevated to more than 3 or 4 mmol/L

Type A – Tissue hypoxia

  • Hypo-perfusion  - shock, sepsis, heart failure
  • Anaerobic exercise

Type B  - Metabolic disorders

  • Liver disease (reduced clearance)
  • Drugs – metformin, propofol, antiretroviral medication, linezolid
  • Ethanol
  • Thiamine deficiency
  • Malignancies
  • Genetic metabolic defects - glucose-6-phosphatase deficiency, pyruvate dehydrogenase deficiency; defects of gluconeogenesis; mitochondrial disease (e.g. MELAS)

Glycolate, a metabolite of ethylene glycol,  causes a large false increase when lactate is measured on an ABL blood gas analyser and a smaller false increase when measured on the main chemistry analyser.

Additional Information

This test must be processed urgently.  Lactate starts to rise within 3 minutes from sample collection.

Minimum Volume

45 uL collected into a 45 uL plastic capillary tube

Electronic Information

Registration Code


HL7 mapping code