System for mechanical measurements during cardiopulmonary resuscitation in humans

A computer-based mobile data acquisition system that was designed and built for measurement of the mechanical properties of the human chest and the resultant vascular pressures are discussed. During manual cardiopulmonary resuscitation (CPR), a short cylindrical module was placed between the rescuer´s hands and the patient´s chest. This module, which was attached to an easily manipulated position-sensing arm, measured force and acceleration at the sternum. Three-dimensional position and orientation of the module were measured, as well as the component of the applied force which was perpendicular to the sternum. The central venous and aortic pressures were measured by high-fidelity pressure transducers. All transducer signals were recorded by digital computer. Real-time feedback of sternal force and displacement and vascular pressures was provided to the rescue team via chart recordings. An audible signal was produced as an aid in maintaining the desired compression rate and duration. The system´s mobility permitted rapid implementation at any hospital location.