New results in the area of mechanical cardiopulmonary resuscitation indicate that during external cardiac massage, the blood flow is achieved both by direct cardiac compression and a generalized increase in the intrathoracic pressure. While, in accordance with the classical theory, the heart is compressed between the sternum and the vertebral column, the thoracic pump mechanism requires a consideration of all blood-carrying structures within the thorax as elastic tubes or chambers that are capable of being compressed by externally administered pressure. Only such variations of the technique presently used may be of benefit which can be achieved with simple adjuncts and which have a positive effect on both mechanisms of blood flow.