Metabolic
Lactate
Lactate is a metabolic by-product of anaerobic glucose breakdown that rises when tissue oxygen delivery fails to keep pace with demand. At the point of care it is measured on a small whole-blood sample within seconds to minutes, supporting rapid recognition of shock, sepsis and severe illness.
Why it is measured
Lactate is a useful marker of tissue hypoperfusion and metabolic stress, and serial measurements help indicate whether resuscitation and treatment are working, though a raised level is not specific to a single cause.
| Typical range | Adult resting venous lactate is indicatively 0.5 to 2.2 mmol/L, with arterial samples typically a little lower at about 0.5 to 1.6 mmol/L. Values above 2 mmol/L are commonly regarded as raised and above 4 mmol/L as markedly elevated. Ranges vary by analyser, sample type and method. |
|---|---|
| Sample | Whole blood: capillary fingertip, venous or arterial, depending on the device. Some handheld meters require as little as 0.6 microlitres, and several blood gas systems measure lactate from the same syringe used for gases. |
| Turnaround | Typically 10 to 60 seconds on handheld meters, and around 1 to 5 minutes on cartridge and blood gas analysers. |
Point of care devices that report it
- Nova Biomedical StatStrip Lactate
- Nova Biomedical Lactate Plus
- Arkray Lactate Pro 2
- EKF Diagnostics Lactate Scout+
- Abbott i-STAT (CG4+ cartridge)
- Siemens Healthineers epoc Blood Analysis System
- Radiometer ABL90 FLEX blood gas analyser
Questions, answered
Why measure lactate at the point of care rather than sending it to the laboratory?
Near-patient testing removes transport and centrifugation delays, so a result is available in seconds to minutes, which supports early sepsis screening and resuscitation decisions. Lactate can continue to be generated in an unprocessed tube if it is not analysed or chilled promptly, so prompt near-patient analysis can be more representative. This is general operational guidance and not patient-specific advice.
Does the sample type, capillary, venous or arterial, change the result?
Yes. Sample type influences the reading, and venous values tend to run slightly higher than arterial values. Prolonged tourniquet use, a clenched fist or recent strenuous exercise can transiently raise lactate. Follow the device instructions and record the sample type so results are interpreted in context.
Can point-of-care lactate replace laboratory lactate?
For triage and trend monitoring many services rely on validated point-of-care meters, but methods, calibration and reference ranges differ between devices and the central laboratory. Confirmatory or quality-controlled laboratory testing may be required for borderline or critical values, in line with local policy.