Final answer:
The height of a tourniquet above the site depends on the specific situation and purpose, such as for an IV bag used for intravenous infusions. The pressure needed to allow the fluid to enter the vein can be calculated based on the blood pressure in the vein and atmospheric pressure.
Step-by-step explanation:
The height of a tourniquet above the site depends on the specific situation and purpose. In the case of an IV bag used for intravenous infusions, the bag must be placed at a height that creates enough pressure for the fluid to enter the vein. The pressure needed can be calculated based on the blood pressure in the vein and atmospheric pressure.
Tourniquets are typically placed a few inches above the site where the needle will be inserted, not at a specific height in relation to blood pressure or IV fluid administration.