The invention relates to an apparatus (1) for assisting cardiopulmonary resuscitation by applying compressions to the chest of a patient to stimulate blood circulation. The apparatus (1) comprises a pneumatic compressor assembly (10) including at least an actuator (1) and an application member (20) for pressing against an application site of the patient. The pneumatic compressor assembly (10) is connected or connectable to a pressurized gas container (70) by a connecting member (50) while the connecting member (50) is adapted for the operation of the pneumatic compressor assembly (10) with a gas or mixture of gas in liquid form.
