physiology

"The ' measures the volume of s compared to the total (red blood cells and ). 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. s calculate the hematocrit by multiplying the the red cell number (in millions/mm3) by (MCV, in s). When so assayed, it is subject to the vagaries inherent in obtaining an accurate measurement of the MCV (see Chapter 152)."

"is the packed spun volume of whole that is made up of s and is expressed as a percentage of total . It can be measured or calculated as Hct = (RBC × )/10. Abnormal calculated hematocrit values may occur as a result of interferences that may cause erroneous RBC and MCV measurements which include very high count, high concentration of s, or … An increased hematocrit may be due to or . Decreased values may be due to , , , or . Pregnancy may also cause slightly decreased hematocrit due to an increase in blood volume."