A volunteer study showed that tourniquets were just as effective at occluding distal blood flow measured by doppler signal when placed below the elbow or knee compared with above those joints. A makeshift windlass tourniquet, a rubber tube tourniquet, and a blood pressure cuff were all effective. Digital ‘pressure point control’ failed to maintain control of brachial or femoral artery flow.
J Trauma. 2009 Mar;66(3):672-5