The development of feedback monitoring device for CPR.

CPR (Cardio-Pulmonary Resuscitation) is known as the most basic aid in emergency situations. For successful CPR, the chest compression depth, cycle, and compressing point are important factors. In I.C.U.'s (Intensive Care Unit) and E.R.'s (Emergency Room), monitoring devices are used to monitor the chest compressions correctly. These devices use accelerometers or pressure sensors. Because the mattress under the patient compresses together, these devices overestimate the compression depth. To overcome this problem, two accelerometers are used in this study, one is on the chest, and the other is between the back of the patient and the mattress. The measurement setup and algorithm to estimate the compression depth are explained. According to the experiment with the mannequin, when CPR is done on a mattress, the actual compression depth was 43.7 mm (S.D. 1.93 mm). The estimated compression depth was 61.4mm (S.D. 1.87 mm) when using an acceleration sensor. This includes the depth of compression of the mattress. When we use two acceleration sensors, estimated compression depth is 44.6mm (S.D. 1.59 mm), which is similar to the actual compression depth. In conclusion, the dual accelerometer gives more accurate estimated compression depth than conventional devices.