Design of a system to detect the force applied by tourniquets in a manikin's limb.

Massive hemorrhage remains the number one cause of preventable death in trauma worldwide. However, immediate intervention by a bystander can significantly improve the survival of the injured person. In this context, the tourniquets represent the most quick and effective devices for stopping arterial and venous blood flow. The aim of this study was to implement a system to detect the force applied by a tourniquet on a simulated limb, without blood flow. The system we designed is characterized by four low-cost force sensing resistors placed on each lower limb of a manikin, below the groin. Tests on 21 tourniquets, revealed that our system is able to detect the force applied for 60 minutes, also discriminating between turns. Hence, this system can be used to compare the performance of different types of devices, but also to assess proper tourniquet placement in trainees and trauma care providers, thus making it a versatile low-cost device.