Avoiding tourniquet-induced neuropathy through cuff design.
Pneumatic tourniquets are routinely used in limb surgery to provide a bloodless operating field, but they are known to cause nerve injuries. Simulation results based on the hypothesis that axial compression of nerves is responsible for a certain class of these mechanically induced injuries are in substantial accord with clinical observations. A model of the limb and tourniquet that treats the tissue as a linearly elastic solid is presented and is used to predict the induced axial strains. The smallest axial strains are induced by a tourniquet design for which the applied pressure distribution rolls off as gradually as possible; according to the axial-strain hypothesis, such a design will markedly decrease a tourniquet's inherent potential for injury. Use of a wider cuff in and of itself will not reduce axial strain, so if the hypothesis is correct, a wider cuff would not be intrinsically safer than a regular cuff, a result that is contrary to current opinion.
Hodgson
A J
AJ
Mechanical Engineering Department, University of British Columbia, Vancouver, Canada.
D004867:Equipment Design; D006801:Humans; D007511:Ischemia; D008954:Models, Biological; D009408:Nerve Compression Syndromes / Q000209:etiology / Q000517:prevention & control; D009422:Nervous System Diseases / Q000209:etiology / Q000517:prevention & control*; D017933:Peripheral Nervous System / Q000098:blood supply; D013312:Stress, Physiological / Q000209:etiology / Q000517:prevention & control; D014111:Tourniquets / Q000009:adverse effects*