[Assessment of external cardiac massage efficiency or Kouwenhoven revisited (author's transl)].

The external cardiac massage mechanism is commonly related to the ventricles compression between the vertebral block and the sternum. This over-simple explanation must be reconsidered. Following recent data, the intra thoracic pressure changes take probably a major part in it efficiency. Six patients have been studied by hemodynamic intra aortic measurements and Doppler carotidian velocimetry. Intra thoracic pressure have been recorded by an oesophageal catheter. Results are in agreement with the prominent part of the intra thoracic pressure variations. Various external cardiac methods are investigated following this monitoring. Some aspects of the classical management of the cardiac arrest have to be discussed.