Safety and efficacy of a new tourniquet system

We routinely used the tourniquet system in 120 consecutive upper limb surgeries performed under general anaesthesia in our operating room instead of our clinic. Cuff pressure was automatically regulated to additional 100？mmHg based on the SBP and was renewed every 2.5 minutes intervals.An excellent bloodless field was obtained in 119 cases, with the exception of one case of a 44-year-old woman who underwent internal screw fixation of metacarpal fracture. No complications, such as compartment syndrome, deep vein disorder, skin disorder, paresis, or nerve damage, occurred during or after surgery.This new tourniquet system, synchronized with SBP, can be varied to correspond with sharp rises or drops in SBP to supply adequate pressure. The system reduces labor needed to deflate and re-inflate to achieve different pressures. It also seemed to contribute to the safety in upper limb surgery, in spite of rare unexpected oozing mid-surgery, by reducing tissue pressure.In upper limb surgery, the pneumatic tourniquet is an essential tool to provide a clean, bloodless surgical field, which improves visualization of anatomical structures and prevents iatrogenic failure. Optimal inflation pressure to accomplish these objects without injuring normal tissue is not yet established. Severe complications are very rare with the use of conventional pressure-retained type tourniquets in upper limb surgery [1-3]. However, temporary or irreversible tissue damage may occur even with appropriate tourniquet usage [1,2]. Most cases of neurologic complications are due to excessively high inflation pressure or long period of inflation [1-5]. Graham et al. [6] used a fully implantable biomedical pressure transducer with cadaver upper extremities to demonstrate that tourniquet cuffs transmit high pressures to peripheral nerves under its midpoint without significant attenuation by the intervening soft tissues in an upper arm; he also reported a steep gradient of perineural pressure that decreased n