Local compression 5 minutes: blood coagulation takes 5 ~ 10 minutes, and as a kind of anticoagulant medicine pressing 5 minutes is obviously not appropriate.

　　Local compression for 10 minutes: low-molecular-weight heparin sodium injection subcutaneously for 10 minutes can prolong the coagulation mechanism, prothrombin time, pressing for 10 minutes can not reach the anticoagulation process.

　　15 to 20 minutes: this is the best press time. It is important to note that cotton swabs should not be used for press.