Hemoglobin carries oxygen to cells while hematocrit measures the percentage of red blood cells in total blood volume. Abnormalities can be caused by dehydration or fluid overload. Low hemoglobin levels can indicate anemia while high levels can lead to polycythemia vera. Hemoglobin and hematocrit levels are directly related and are used to determine baseline levels and response to transfusions. Medications and fluid intake can affect test results.
Hemoglobin and hematocrit are two important components of a complete blood count, a test a doctor might order to determine if there are any abnormalities in a patient’s blood chemistry. Both “hemoglobin” and “hematocrit” refer to specific characteristics of red blood cells, but they measure different things. Hemoglobin is an oxygen-binding compound that carries oxygen to cells, and the hemoglobin test measures how much of this compound is present. The hematocrit test determines how much of your total blood volume contains red blood cells.
Doctors require hemoglobin and hematocrit along with other blood chemistry measurements to get a complete picture of a patient’s blood chemistry and overall level of health. Some things can distort the measurements. A severely dehydrated or fluid-laden patient will have abnormal blood volume due to changes in blood plasma level, for example. Dehydrated patients might have an unusually high hematocrit level because there are more red blood cells as a percentage of the total blood volume.
Normal hemoglobin levels for women range from 12-16 grams per deciliter and men have slightly higher values, 14-18. If the levels are low, it can indicate that a patient has anemia. Lack of hemoglobin means that the patient’s body will not get enough oxygen. This can lead to the development of fatigue and other problems, including organ failure, slow wound healing, and secondary complications. Patients may also have too much hemoglobin, as seen in conditions such as polycythemia vera.
Red blood cells are basically vessels for hemoglobin, so there is a very direct relationship between hemoglobin and hematocrit. Patients who have low red blood cell levels might have low hemoglobin levels because their bodies don’t have enough red blood cells to meet their needs. Likewise, high levels can lead to an excess of this compound. Patients who need transfusions to replace lost blood or make up for low blood cell production might receive a hemoglobin and hematocrit test to determine their baseline levels and to see how they respond to the transfusion.
Hematocrit values can range from 40 to 54% in men and 36 to 48% in women. With a hemoglobin and hematocrit test, the doctor will want to know if the patient is taking any medications or has ingested unusually high or low levels of fluids. If the values appear to be abnormal, these could be considered as factors before exploring possible diseases that could be causing a high or low red blood cell concentration.
Protect your devices with Threat Protection by NordVPN
