Red Blood Cell Mass Concentration (Serum or Plasma)
This test measures the total mass of red blood cells present in a sample of your blood or body fluid.
["Understanding your red blood cell mass can help assess overall blood health."]
Key facts at a glance
- LOINC
- 34964-7
- Short code
- OF RBC-Imp
- Synonyms
- OF RBC-Imp
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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
What Does This Test Measure?
The test quantifies the combined weight of red blood cells (RBCs) in a given volume of your blood or fluid sample. RBCs carry oxygen throughout your body, and their mass concentration can reflect their overall quantity and potential health status.
Why Might You Need This Test?
Your healthcare provider may order this test if they suspect conditions affecting RBC production, distribution, or function, such as anemia, polycythemia, or other blood disorders. It may also be used in research or specialized clinical scenarios where precise RBC mass assessment is critical.
Common Uses and Contexts
This test is less commonly performed in routine clinical settings compared to standard RBC counts. It may be used in advanced diagnostic workflows, such as evaluating complex hematologic conditions, monitoring chronic diseases, or conducting specialized studies on blood components.
Sample Collection and Preparation
A blood sample is typically drawn from a vein in your arm. If this test is performed on other fluids (e.g., plasma or cerebrospinal fluid), the sample type will be specified by your provider. Proper handling and storage of the sample are essential to ensure accurate results.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
RBC Mass Concentration
Frequently asked questions
How Might This Test Result Affect My Care?
FAQ Question 1
Your provider will discuss the result with you and may recommend additional tests or treatments based on the findings. Follow their guidance closely to address any underlying health concerns.
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