Hematocrit

Hematocrit (Ht, Hct, or HCT), also known by Hematocrit#Names several other medical names, is a volume fraction#Volume percent volume percentage (vol%) of Red blood cell red blood cells (RBCs) in a diagnostic blood sample, measured as part of a blood test. Because the purpose of red blood cells is to transfer oxygen from the lungs to body tissues, a blood sample's hematocrit—the red blood cell volume percentage—can become a point of reference of its capability of delivering oxygen. Hematocrit levels that are too high or too low can indicate a blood disorder, dehydration, or other medical conditions. An abnormally low hematocrit may suggest anemia, a decrease in the total amount of red blood cells, while an abnormally high hematocrit is called polycythemia. Both are potentially life-threatening disorders. Quotes The hematocrit measures the volume of red blood cells compared to the total blood volume (red blood cells and Blood plasma plasma). The normal hematocrit for men is 40 to 54%; for women it is 36 to 48%. This value can be determined directly by microhematocrit centrifugation or calculated indirectly. Hematology analyzer Automated cell counters calculate the hematocrit by multiplying the the red cell number (in millions/mm3) by Mean corpuscular volume mean cell volume (MCV, in Litre#SI prefixes applied to the litre femtoliters). When so assayed, it is subject to the vagaries inherent in obtaining an accurate measurement of the MCV (see Chapter 152). Henny H. Billett, Chapter 151. Hemoglobin and hematocrit Clinical Methods: The History, Physical, and Laboratory Examinations 3rd 1990 Boston Butterworths https://www.ncbi.nlm.nih.gov/books/NBK259/ (Clinical Methods, 3rd edition, edited by H. Kenneth Walker. W. Dallas Hall, and J. Willis Hurst) Hematocrit is the packed spun volume of whole blood that is made up of red blood cell RBCs and is expressed as a percentage of total blood volume. It can be measured or calculated as Hct = (RBC × Mean corpuscular volume MCV)/10. Abnormal calculated hematocrit values may occur as a result of interferences that may cause erroneous RBC and MCV measurements which include very high White blood cell WBC count, high concentration of platelets, or Hemagglutination agglutinated RBCs … An increased hematocrit may be due to dehydration or polycythemia. Decreased values may be due to anemia, Water intoxication overhydration, kidney failure, or Systemic inflammation chronic inflammatory conditions. Pregnancy may also cause slightly decreased hematocrit due to an increase in blood volume. Sirisha Kundrapu and Jaime Noguez, Chapter Six — Laboratory Assessment of Anemia. Section 3.1.2 Hematocrit Advances in Clinical Chemistry (Book Series); Volume 83 Academic Press (sciencedirect.com) 2018 197–225 Advances in Clinical Chemistry https://www.sciencedirect.com/topics/chemistry/hematocrit Chapter Abstract & Introduction External links Hematocrit Blood Test Human Bio Media https://www.humanbiomedia.org/hematocrit-lesson/ Category:Health Category:Medicine Category:Physiology