The tourniquet test is part of the new WHO case definition for dengue. The test is a marker of capillary fragility and it can be used as a triage tool to differentiate patients with acute gastroenteritis, for example, from those with dengue. Even if a tourniquet test was previously done, it should be repeated if
•It was previously negative
•There is no bleeding manifestation
How to do a Tourniquet Test
1. Take the patient's blood pressure and record it, for example, 100/70.
2. Inflate the cuff to a point midway between SBP and DBP and maintain for 5 minutes. (100 + 70) ÷ 2 = 85 mm Hg
3. Reduce and wait 2 minutes.
4. Count petechiae below antecubital fossa. See image at right.
•A positive test is 10 or more petechiae per 1 square inch.