Misc
Other Tools
Manual RBC or WBC count on a hemocytometer
(# of cells x dilution factor x depth factor) / area
For the dilution factor, if it is 1:10, you would use 10. The depth factor is usually 10 unless otherwise noted.
Corrected reticulocyte count (This formula is to be used for patients with anemia):
% reticulocytes x Hct / 45
Corrected WBC count (Used when nucleated RBCs are present):
(WBC count x 100) / (100 + # of nucleated RBCs)
Oxygen dissociation curve:
In hypoxic or anemic states, 2,3 DPG will increase (decreasing it’s affinity for O₂) which will release more O₂ to tissue. The oxygen dissociation curve will shift to the right.
Specimen Handling
Lavender top EDTA tube with less than 2mL of blood:
The excess anticoagulant in the tube will shrink the RBCs leading to a decreased hematocrit.
Know your vocabulary!
Anisocytosis – change in normal size of RBC
Poikilocytosis – change in normal shape of RBC
Polychromasia – bluish tint of immature erythrocytes (reticulocytes)
Dysplasia:
Dysplasia is defined as the enlargement of an organ or tissue by the proliferation of cells of an abnormal type, as a developmental disorder or an early stage in the development of cancer. The prefix dys- means “bad”, and the suffix plasia means “formation,” so when you see dysplasia you can think “bad formation.”
Neoplasm:
A neoplasm is defined as a new and abnormal growth of tissue in some part of the body, especially as a characteristic of cancer.