Why do we take both hematocrit and red cell count?
To expound on John’s answer, the need for RBC count as well as hematocrit (HCT) is because you can have for example a low HCT with normal sized RBC’s which means something different than a low HCT with small RBC’s (microcytic RBC’s). The first is most likely from bleeding acutely or bone marrow suppression, while the latter can mean a disease state or a long term, slow bleed. The other piece that we didn’t talk about is hemoglobin level (HGB) which tells us how much HGB is in a certain volume of blood. HGB and HCT (the well known “H&H”) go together and the HCT should be approximately 3 times the HGB normally. Again, the RBC size and HCT compared to the HGB concentration tells a varied story, that once you know how to read it they can help treat a patient the proper way. When you understand HGB, HCT and RBC count you can begin adding in MCH (mean corpusular hemoglobin = average amount of HGB in the RBC’s being sampled), MCHC (mean corpuscular hemoglobin concentration = average amount of
