Hemoglobin concentration in whole blood measured by impedance
This test measures the amount of hemoglobin in your blood, which helps assess your red blood cell health and overall blood oxygen-carrying capacity.
["Hemoglobin levels help diagnose and monitor conditions like anemia or polycythemia."]
Key facts at a glance
- LOINC
- 31100-1
- Short code
- Hct VFr Bld Imped
- Synonyms
- Hct VFr Bld Imped
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 36
- Ref high
- 50
- Critical range
- 18 N/A – 60 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- impedance
- CPT
- 85014
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order this test if you have symptoms like fatigue, pale skin, shortness of breath, or unusual tiredness. It’s also used to monitor conditions like anemia, blood loss, or certain blood disorders.
What Does the Test Involve?
A small blood sample is taken from a vein, usually in your arm. The sample is then analyzed using an impedance method to measure hemoglobin concentration.
What Are Common Results?
Results are reported as a concentration value (typically in grams per deciliter, g/dL). While reference ranges vary by lab, lower levels may suggest anemia, while higher levels might indicate polycythemia or dehydration.
How Does This Test Relate to Other Blood Tests?
Hemoglobin is often measured alongside other blood tests like red blood cell count (RBC) and hematocrit (Hct) to provide a full picture of your blood health.
Reference range
Adult males: 38-50%; Females: 36-44%N/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Low hemoglobin levels can indicate anemia, which may stem from iron deficiency, chronic illness, or blood loss. High levels may suggest conditions like polycythemia or dehydration. Regular monitoring can help manage chronic conditions like heart disease or kidney disorders.
Short name
Hemoglobin (Impedance Method)
Frequently asked questions
What does an abnormal hemoglobin result mean?
How often should I get this test?
Can lifestyle changes affect hemoglobin levels?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy