Jan 8, 2018




Clinical Hub,Tools & Resources,UWHC Lab Test Directory,Chemistry

Anion Gap

Anion Gap (LYTE) Chemistry Lab Test

Name: Anion Gap

Test Name: Anion Gap

Health Link Test Code: LYTE

LIS Test Code: LYTS

CPT Code(s): See Electrolytes Panel

Included In: Electrolytes panel, Basic Metabolic Panel (BMP) and Comprehensive Metabolic Panel (CMP)

Methodology: Ion Selective Electrode and/or Enzymatic

Days Performed: Daily, 24 hours.

In-Lab Turnaround Time: 4 hours.

Stat In-Lab Turnaround Time: 1 hour.

Specimen: Blood

Collection Container: Green cap with yellow ring (PST)

Also Acceptable: Green top, Red cap with yellow ring (SST), Red top

Collection Instructions:

Tube must be at least one quarter full.

Collection Volume: 1 mL

Pediatric Collection Volume: 0.5 mL

Sample Analyzed: Plasma or serum

Testing Volume: 0.5 mL

Pediatric Testing Volume: 0.2 mL

Specimen Processing:

Centrifuge. If a complete barrier has not formed, transfer cell-free plasma/serum to plastic vial. Tube must be at least one quarter full. Refrigerate specimen.

Specimen Transport:

Transport specimen to the laboratory. Transport with coolant pack if coming from clinic location.


0 days and up: 7-14 mmol/L

Interpretation Type: Reference Interval

Additional Information:

The anion gap is calculated by subtracting the sum of the chloride and total carbon dioxide from the sodium result.