Manual Sahli Pipette Method

Figure 6-4.—Blood cell pipettes. (mm³) of blood. The normal is as follows: adult male 5.4 + .8 red blood cell million/mm³ count adult female 4.8 + .6 million/mm³ newborn 5.1 + .9 million/mm³ A lower count is usually a sign of anemia. Manual Sahli Pipette Method The materials listed below are required to per- form a red blood cell count using the manual Sahli pipette method: . Hemacytometer set Microscope with lamp Red cell pipette Suction tube Laboratory chits 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. Procedure 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 horizon- tal 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. 6-6