Four analytes. One SST. The Electrolyte Panel measures sodium, potassium, chloride and carbon dioxide, and you order it when you need the electrolyte picture without a full metabolic workup. Results are reported 24-48 hours from receipt of sample.
At a glance
| Detail | Information |
|---|---|
| Test name | Electrolyte Panel (EP) |
| Category | Chemistry |
| Specimen | Blood (SST) |
| Turnaround | 24-48 hours from receipt of sample |
| Ordered by | Requesting physician |
What it detects
| Group | Analyte | Individual order code |
|---|---|---|
| Cations | Sodium | NA |
| Cations | Potassium | K |
| Anion | Chloride | CL |
| Anion | Carbon Dioxide | CO2 |
EP is a subset of larger panels. The Basic Metabolic Panel and Complete Metabolic Panel both include these four analytes, and so does the Renal Function Panel.
When to order it
Order EP when the clinical question is limited to sodium, potassium, chloride and CO2.
- Targeted electrolyte assessment. You want these four values and nothing else on the report.
- Follow-up of a prior electrolyte result. You are rechecking one or more of the four analytes.
- Routine checkups. Basic chemistry screening is part of a routine checkup, and EP covers the electrolyte component.
If you also need glucose, calcium, BUN or creatinine, order a BMP. If liver markers are in scope, order a CMP. If you need a single analyte, sodium, potassium, chloride and CO2 can each be ordered individually on the same SST requisition.
Specimen collection
| Parameter | Requirement |
|---|---|
| Tube | SST (Serum Separator Tube) |
| Order of draw | 3rd (after blue/coag, after blood culture) |
| Inversions | 5-10 times |
| Stability, room temperature | 24 hours |
| Stability, refrigerated | 3 days |
| Transport | Refrigerated |
Handling points that matter for this panel:
- Avoid hemolysis. It falsely raises potassium.
- Check the spin. A properly centrifuged SST shows pale yellow serum on top, a gel barrier in the middle and packed red cells at the bottom. Serum is what gets tested. Do not disturb the red cell layer when aliquoting.
- Verify two identifiers before drawing. Use full name and date of birth.
Understanding the report
Sodium, potassium, chloride and carbon dioxide are reported in mEq/L. Each result is printed with its reference range. Values outside range carry an H or L flag, so abnormal results stand out on a quick read.
Reference ranges are printed on the report and can differ between report formats. In one TLS sample report, the ranges were:
- Sodium 133-144
- Potassium 3.5-5.4
- Chloride 95-107
- Carbon dioxide 19-31
A second sample report printed different ranges for the same four analytes. Interpret every result against the range on that patient’s report.
Why order it from Total Lab Solutions
- Defined turnaround. Results are reported 24-48 hours from the time we receive the sample.
- Flexible ordering. Order EP as a panel, or order sodium, potassium, chloride and CO2 individually. All are SST tests.
- Broad menu, one lab. TLS offers 9 hematologic panels and 90+ individual tests, so electrolytes can be ordered alongside the rest of your chemistry work.
- Direct line to the lab. Call 248.800.6626 or fax 248.800.6656. TLS operates from Troy, MI and Spring, TX.
Frequently asked questions
Which analytes are included in the electrolyte panel (EP) and does it include CO2?
EP includes sodium, potassium, chloride and carbon dioxide. Yes, CO2 is part of the panel.
What are the standard adult reference ranges for sodium, potassium, chloride, and CO2 on the EP?
Reference ranges print on every report, with results in mEq/L, and you should interpret against the printed range. One TLS sample report shows sodium 133-144, potassium 3.5-5.4, chloride 95-107 and CO2 19-31. Another sample report prints different ranges, which is why the range on the patient’s own report governs.
What specimen type, collection requirements, and handling steps help prevent hemolysis and falsely elevated potassium?
The specimen is blood collected in an SST. Draw it third in the order of draw, after blue/coag and blood culture tubes. Invert 5-10 times. Avoid hemolysis, because it falsely raises potassium. Transport refrigerated. SST stability is 24 hours at room temperature and 3 days refrigerated. Verify full name and date of birth before drawing.
What is the typical turnaround time for an electrolyte panel, and is STAT testing available?
Results are reported 24-48 hours from receipt of sample. STAT availability is not specified in our published materials. Call 248.800.6626 to ask about urgent needs.
When should clinicians order an EP instead of a basic or comprehensive metabolic panel, and what CPT code applies for billing?
Order EP when you only need sodium, potassium, chloride and CO2. A BMP adds calcium, creatinine, glucose, BUN and the BUN/creatinine ratio, such as creatinine. A CMP adds albumin, alkaline phosphatase, ALT, AST, total bilirubin, total protein and the A/G ratio. Chloride is also available as a standalone test: Chloride. We do not list a CPT code for EP in our published materials. Confirm billing codes with your billing team or contact the lab.
Order the electrolyte panel alone or alongside the rest of your chemistry menu: Explore our tests
