Wide tourniquet cuffs more effective at lower inflation pressures.

Longitudinal and radial tissue-fluid pressure distributions were determined beneath and adjacent to wide (12 and 18 cm) pneumatic tourniquet cuffs placed on intact human cadaveric arms and legs, respectively. Tissue fluid pressures exhibited relatively broad maxima at midcuff, and in most cases showed no differences at the various depths studied. Limb circumference was not a determining factor in the transmission of pressure to deeper tissue. We also investigated the effect of four cuff sizes (4.5, 8, 12, and 18 cm) on eliminating blood flow to the lower legs of normal subjects. The cuff pressure required to eliminate blood flow decreased as cuff width increased; thigh circumference was a determining factor in the pressure required to eliminate blood flow while using the smaller cuffs, but not while using the 18-cm cuff. Thus, wide cuffs transmit a greater percentage of the applied tourniquet pressure to deeper tissues than conventional cuffs; accordingly, lower cuff pressures are required, which may minimize soft-tissue damage during extremity surgery.