Sudden cardiac arrest is defined as the sudden cessation of the mechanical activity of the heart, confirmed by the absence of signs of circulation. Two actuations are key for patient survival after cardiac arrest: early cardiopulmonary resuscitation (CPR) and early defibrillation. CPR consists in applying chest compressions and ventilations to the patient to artificially maintain a minimal flow of oxygenated blood to the vital organs.

The quality of chest compressions is related to patient's survival. For that reason, resuscitation guidelines recommend the use of feedback devices that monitor CPR performance in real-time. These devices are usually placed between the chest of the patient and the rescuer's hands, and guide the rescuers towards the target compression depth and rate.

This thesis explores new alternatives to provide feedback on the quality of chest compressions during CPR. Two strategies were studied: the use of the transthoracic impedance (TTI) signal, which is acquired by current defibrillators through defibrillation pads, and the use of the chest acceleration, which could be acquired using an extra pad.