Harr Hematology Practice Test

Insufficient centrifugation can lead to a false increase in hematocrit (Hct) value. When blood is centrifuged, it separates into plasma and cellular components, with the cellular elements settling at the bottom of the tube. If the centrifugation is not performed long enough or at the correct speed, the separation will be incomplete, resulting in some cells remaining suspended in the plasma. This incomplete separation means that the measurement of the packed cell volume, which is used to determine the hematocrit, will include not only the properly settled red blood cells but also a portion of the cells still mixed with plasma. As a result, the overall volume of red blood cells appears higher than it actually is when measured. Consequently, the hematocrit value reported will reflect this falsely elevated level, leading to an inaccurate representation of the patient's true Hct. This phenomenon highlights the critical importance of ensuring proper centrifugation techniques in laboratory procedures to guarantee accurate hematological analyses.