(mm3) of blood. The normal red blood cell count is as follows:
adult male 5.4 + .8 million/mm3
adult female 4.8 + .6 million/mm3
newborn 5.1 + .9 million/mm3
A lower count is usually a sign of anemia.
Figure 6-4.Blood cell pipettes.
Manual Sahli Pipette Method
The materials listed below are required to perform a red blood cell count using the manual Sahli pipette method:
Microscope with lamp
Red cell pipette
Hand held counter
Red cell diluting fluid. 0.85 percent sodium chloride (normal saline) is preferred because of its ready availability and its ability to prevent clumping of red cells.
1. Using well mixed anticoagulated blood or blood directly from a fingerstick, fill the clean, dry, red cell pipette (fig. 6-4) exactly to the 0.5 mark with the aid of the suction tube. Hold the pipette in a nearly horizontal position so that the exact level of the blood can be seen. The curve of the tip may rest on the skin, but the orifice must be free
Figure 6-5.Mixing blood and diluting fluid.