What is the normal plasma volume in the human body?
Apr 07, 2023
Source: Cainiu Health
Dr. Zhang Heyang
Introduction
The normal human plasma volume accounts for 7% to 8% of body weight, and the average person's total blood volume ranges from 4000 to 5000 mL. Blood is able to transport oxygen because red blood cells contain hemoglobin, which binds and carries oxygen. In addition, blood volume is usually related to the body's physiological condition; for example, after drinking large amounts of water, blood volume typically increases.
Normal human plasma volume accounts for 7% to 8% of body weight, and the average person has a total blood volume of approximately 4000 to 5000 mL.
For instance, a person weighing 60 kg would have a blood volume of about 4200 to 4800 mL. Blood normally circulates through the cardiovascular system; this portion is known as circulating blood. Another portion of blood is stored more slowly in organs such as the lungs, liver, and under the skin, and is referred to as reserve or stored blood. Blood is generally composed of blood cells and plasma, with blood cells typically classified into three types: white blood cells, red blood cells, and platelets.
Plasma is an essential component of human blood and appears as a pale yellow liquid. It functions primarily to transport blood cells and help maintain vital nutrients necessary for life. Blood appears red due to the presence of hemoglobin in red blood cells, which enables them to carry oxygen, thus allowing blood to deliver oxygen throughout the body.
In addition, blood volume can also be influenced by physiological conditions—for example, after consuming large amounts of water, blood volume usually increases slightly.
