###1: Red Blood Cell Count in Whole Blood by Manual Method
###3: This test measures the concentration of red blood cells in a whole-blood sample using a manual counting method. It is often used with hemoglobin and hematocrit to help evaluate anemia, polycythemia, and other blood abnormalities.
["###4: A manual red blood cell count helps assess the number of red cells in the blood, but results must be interpreted with other tests and your clinical history."]
Key facts at a glance
- LOINC
- 790-6
- Short code
- RBC # Bld Manual
- Synonyms
- RBC # Bld Manual
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- 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
- Method
- manual-count
- CPT
- 85041
- SNOMED
- 900000000000003001
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
###5: What the Test Measures
###6: Red blood cells carry oxygen from the lungs to tissues throughout the body. The test estimates how many red blood cells are present in a measured volume of blood; it does not directly measure oxygen saturation or red-cell function.
###7: How the Test Is Performed
###8: A blood sample is collected, usually by venipuncture, and red blood cells are counted using a manual laboratory method. The technique requires trained laboratory personnel and careful sample handling and quality control.
###9: A manual red blood cell count may be ordered as part of a complete blood count or when a clinician needs to confirm an automated result. It may be considered for symptoms such as fatigue, weakness, shortness of breath, dizziness, or unusual bleeding.
###10: Understanding the Result
###11: A lower red blood cell count may be associated with anemia, blood loss, nutritional deficiencies, or other conditions, while a higher count may occur with dehydration, lung disease, or certain other disorders. Results vary with hydration, altitude, pregnancy, medications, and laboratory technique.
###12: Limitations and Follow-Up
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.
◆Associated findings1
Short name
###2: Manual red blood cell count
Frequently asked questions
###14: Is this the same as a complete blood count?
###16: Does the test tell me how much oxygen my blood is carrying?
###18: Is a manual red blood cell count more accurate than an automated count?
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.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy