How long the tourniquet can be placed for?

If the tourniquet is placed properly and arterial (not only venous) blood flow is completely stopped, it can be safely kept for 2 hours without any lasting effect. Keeping the tourniquet for longer then 2 hours is likely to cause temporary nerve or muscle damage of the limb. Complications of prolonged tourniquet use (i.e. irreversible tissue fibrosis and consequent loss of limb) are likely to occur after 6 hours of the application.