Final answer:
The thoracic pump theory of CPR explains how changes in thoracic pressure during chest compressions can facilitate blood flow.
Step-by-step explanation:
The thoracic pump theory of CPR is a concept that explains how blood flow can be facilitated during cardiopulmonary resuscitation (CPR). During inhalation, the volume of the thorax increases, leading to a decrease in air pressure within the thorax. This decrease in pressure allows venous blood to flow into the thoracic region. On the other hand, during exhalation, the increased pressure within the thoracic cavity helps to move blood into the heart. This theory highlights the importance of chest compressions in CPR to create changes in thoracic pressure and facilitate blood flow.