what is Blood strain?

Your blood strain is the force with which your heart is pumping blood thru your arteries. It continues the blood shifting via the body and makes it posible for blood to drift not only "downstream" however additionally "upstream"-as while it is carried from the legs again up to the coronary heart. stress of Blood is highest in the arteries, particularly in the ones nearest the coronary heart. this is why, whilst an artery is reduce, blood shoots to the floor, as although it have been squeezed out through effective strain.

This blood is vivid purple, due to the fact the purple blood cells deliver a complete load of oxygen from the heart on their manner thru the arteries. strain in the veins is plenty decrease than it is in the arteries, so when a vein is reduce, blood has a tendency to trickle slowly from the wound. This blood is a dark, purplish purple, due to the fact rather than oxygen the blood is now wearing carbon dioxide. Blood stress is lowest in the capillaries. these are so tiny that handiest a unmarried pink blood mobile (which is so small that it takes nearly 3,2 hundred of them to make an inch) can undergo at a time.

Your medical doctor measures your blood stress by way of fastening an hermetic bag around your arm and pumping into it. This fills the bag with compressed air. whilst the pressure of this compressed air has tightened the bag simply enough to stop the drift of blood thru your arm, the physician knows that the air stress within the bag and the blood pressure to your frame are the identical. by way of measuring the air stress, he can tell what the blood pressure is. Air pressure is measured through how high up it will push the "liquid metal" known as mercury in a tube. (See the article on air compression.) regular blood stress would be enough to send the mercury 120 to 150 millimeters (4Vi to five Vi inches) excessive.

If a person's blood pressure is an awful lot higher than this, it could be dangerous. there are various motives why someone can also have this, however the normal motive is that his blood vessels have contracted and aren't as large as they need to be. The smaller the blood vessel, the tougher the heart need to paintings to pressure sufficient blood thru it. people with high blood pressure have to rest as plenty as feasible, so that their our bodies will not want as a great deal oxygen as they do when they are active. additionally, their docs will deliver them unique diets and medicines that make their blood vessels larger. high blood pressure generally bothers handiest older human beings. youngsters very seldom be afflicted by it.