Diagnosing and monitoring patients with lactic acidosis
Photometric, Lactate Oxidase/Peroxidase (VITROS Dry Slide)
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Lactic Acid (L-lactate)
Lactic Acid (L-lactate)
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Collection Container/Tube: Grey top (potassium oxalate/sodium fluoride)
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
1. Collection must be at least 1 mL in a 2-mL draw tube or at least 2 mL in a 4-mL draw tube.
2. Spin down and separate plasma from cells.
Additional Information: Patient's age and sex is required.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Plasma NaFl-KOx||Frozen||30 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
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 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 >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 (eg, shock, hypovolemia, heart failure, pulmonary insufficiency), metabolic disorders (eg, diabetic ketoacidosis, malignancies), and toxin exposures (eg, ethanol, methanol, salicylates).
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
< or =2 years: 0.6-3.2 mmol/L
>2 years: 0.6-2.3 mmol/L
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 Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
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 DLAC / D-Lactate, Plasma.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
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
Method Description Describes how the test is performed and provides a method-specific reference
The instrument used is a Vitros 350. Lactate in the specimen is oxidized by lactate oxidase to pyruvate and hydrogen peroxide. The generated hydrogen peroxide oxidizes the 4-aminoantipyrine, 1,7-dihydroxynaphthlaene dye system in a horseradish peroxidase-catalyzed reaction and results in a dye complex. Each mole of lactate oxidized results in 0.5 mole of the dye complex. The specimen is incubated at 37 degrees C for 5 minutes and the intensity of the dye complex is measured spectrophotometrically at 540 nm.(Package insert: Vitros Chemistry Products Instructions for Use - LAC, Version 7.0 Ortho-Clinical Diagnostics, Inc. Rochester, NY 14626, 2012)
PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Sunday; Continuously
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Same day/1 day
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and result codes of this test.
LOINC codes are provided by the performing laboratory.
|Test ID||Test Order Name||Order LOINC Value|
|Result ID||Test Result Name||Result LOINC Value|