Tourniquet test

Microvascular fragility may be demonstrated by a positive "tourniquet test"; this test is performed by inflating a blood pressure cuff on the arm to midway between systolic and diastolic blood pressures for five minutes. The pressure is released for at least one minute and the skin below the cuff is examined for petechiae. A finding of 10 or more petechiae in a one square inch area is considered positive.