RBC Count: CPT 85041

CPT Code: 



 Whole blood


Tube fill capacity 

Minimum Volume: 

0.5 mL 


Lavender-top (EDTA) tube


Automated cell counter


Invert tube immediately 8 to 10 times once tube is filled at time of collection.  

Reference Range:

Males   4.6-6.2 106/µL
Females   4.2-5.4 103/µL


Storage Instructions:  Maintain specimen at room temperature. 


Temperatures   Period 
Room Temperature  1 Day
Refrigerated  3 Days 
Frozen  Unstable 
Freeze/thaw cycles Unstable



Used to evaluate anemia and loss of red cells and suspected polycythemic condition.  Red blood cells are the major component of blood. They are made in the bone marrow and released into the circulating blood. This count is a good indicator of the body’s ability to transport oxygenated blood to body tissues. 

Decrease in RBC count: 

may be the result of red cell loss by bleeding or hemolysis (intravascular or extravascular), failure of marrow production, or may be secondary to dilutional factors (eg, intravenous fluids).  

Increase in RBC count: 

may be the result of primary polycythemia (polycythemia vera) or secondary polycythemia (hypoxemia of lung or cardiovascular disease, increased erythropoietin production associated with renal cyst, renal cell carcinoma, cerebellar hemangioblastoma, or high O2 affinity hemoglobinopathy) including stress polycythemia (hemoconcentration associated with exercise, exertion, fright, etc).


Presence of cold agglutinins may result in falsely low RBC counts.

Causes for Rejection:  

Hemolysis; clotted specimen; tube not filled with minimum volume; improper labeling; transport tubes with whole blood; specimen drawn in any anticoagulant other than EDTA; specimen diluted or contaminated with IV fluid; specimen received with plasma removed; sample more than 48 hours old