Investigation of clinically acceptable agreement between two methods of automatic measurement of limb occlusion pressure: a randomised trial

Abstract Background Development of automatic, pneumatic tourniquet technology and use personalised pressures has improved the safety accuracy surgical systems. Personalisation pressure requires accurate measurement limb occlusion (LOP), which can be measured automatically through two different methods. The ‘embedded LOP’ method measures LOP using a dual-purpose cuff acting as both patient sensor effector. ‘distal distal applied to patient’s finger or toe operating limb, photoplethysmography detect volumetric changes in peripheral blood circulation. been used clinically for many years; embedded was developed recently with several advantages over method. While methods have acceptable comparison manual Doppler ultrasound method, these automatic not directly compared. purpose this study is investigate if agreement. differences pairs upper lower limbs 81 healthy individuals were compared modified Bland Altman analysis. In surgery, it common deviate from setpoint due manipulation. Surgical systems utilise ± 15 mmHg alarm window, whereby deviates by > mmHg, an audiovisual triggered. Therefore, difference (bias) SE, 95% CI bias SD SE between all within ±15 would demonstrate that Results − 0.81 0.75 (bias standard error) than confidence interval 2.29 0.66 mmHg. deviation error 10.35 0.49 These results show Conclusions findings agreement measurement. support cuffs enable accurate, effective simple prescription clinical setting.