The exact pressure to which the tourniquet should be inflated has not been determined. Evidence indicates that pressures greater than necessary have been used for many years. The correct pressure depends on the age of the patient, the blood pressure, and the size of the extremity. Reid, Camp, and Jacob used pneumatic tourniquet pressures determined by the pressure required to obliterate the peripheral pulse (limb occlusion pressure) using a Doppler stethoscope; they then added 50 to 75 mm Hg to allow for collateral circulation and blood pressure changes. Tourniquet pressures of 135 to
255 mm Hg for the upper extremity and 175 to 305 mm Hg
for the lower extremity were satisfactory for maintaining
hemostasis. Younger et al. showed, with a prototype automated limb occlusion pressure apparatus, that tourniquet
pressures could be reduced by 43%. Devices of this type are
now available from several companies.
According to Crenshaw et al., wide tourniquet cuffs are
more effective at lower inflatio n pressure s tha n ar e narrow
ones. Pedowitz et al. showed that curved tourniquets on
conical extremities require significantly lower arterial
occlusion pressures than straight (rectangular) tourniquets
(Fig. 1-1). The use of straight tourniquets on conical thighs
should be avoided, especially in extremely muscular or
obese individuals.
Any solution applied to skin must not be allowed to run
beneath the tourniquet, or a chemical burn may result. A
circumferential adhesive-backed plastic drape applied to the
skin just distal to the tourniquet prevents solutions from
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