Tourniquets should not be tied too tightly, and the use time should be shortened as much as possible. When drawing blood, the tourniquet should be loosened immediately to reduce the time of blood block (and the person who is drawn should not be encouraged to hold the fist for a long time).
(1) the use of tourniquet should be limited to within 1 minute when taking blood from blood lipid items, coagulation items and blood routine items.
(2) the tourniquet binding is too tight and the time is too long (if more than 3 minutes), which will cause the blood block time to be too long. Due to hemolysis, platelet activation, fibrinolysis system activation and other reasons, the results of the above test items will be biased, and even lead to wrong diagnosis and treatment.
(3) when it is necessary to take blood again, when the tourniquet binding time is too long, the blood should be taken again in the opposite arm.