Search our Test Catalog. Specify what to search (name, test code, titles, everywhere) and how to search (begins with, contains)

Unit Code 8665:
Lactate, Plasma

Print Friendly View
Print Page Email Page

Useful For

Diagnosing and monitoring patients with lactic acidosis

Clinical Information

Lactate is the end product of anaerobic carbohydrate

metabolism. Major sites of production are skeletal muscle, brain,

and erythrocytes. Lactate is metabolized by the liver. The

concentration of lactate depends on the rate of production and

the rate of liver clearance. The liver can adequately clear lactate

until the concentration reaches approximately 2.0 mmol/L. When

this level is exceeded, lactate begins to accumulate rapidly. For

example, while resting lactate levels are usually <1 mmol/L,

during strenuous exercise, levels can rise above 20 mmol/L

within a few seconds.

 

Lactic acidosis signals the deterioration of the cellular oxidative

process and is associated with hyperpnea, weakness, fatigue,

stupor, and finally coma. These conditions may be irreversible,

even after treatment is administered. Lactate acidosis may be

associated with hypoxic conditions (e.g., shock, hypovolemia,

heart failure, pulmonary insufficiency), metabolic disorders

(e.g., diabetic ketoacidosis, malignancies), and toxin exposures

(e.g., ethanol, methanol, salicylates).

Reference Values

< or =2 years: 0.6-3.2 mmol/L

>2 years: 0.6-2.3 mmol/L

Interpretation

While no definitive concentration of lactate has been established

for the diagnosis of lactic acidosis, lactate concentrations

exceeding 5 mmol/L and pH <7.25 are generally considered

indicative of significant lactic acidosis.

Cautions

Proper specimen collection and processing techniques are

critical for reliable results.

 

This test does not measure D-lactate, an uncommon, often

undiagnosed cause of lactic acidosis.  See #8878 "D-Lactate,

Plasma."

Clinical Reference

1.   Mizock BA:  The hepatosplanchnic area and hyperlactatemia:

      A tale of two lactates. Crit Care Med. 2001;29(2):447-449

 

2.   Duke T:  Dysoxia and lactate. Arch Dis Child. 1999;81(4):

      343-350

Key