Final answer:
In CPR, we allow the chest to manually expand and contract to mimic the heart's pumping function, which helps maintain blood circulation. Proper hand placement and compression technique are crucial, and CPR training is highly recommended to avoid serious injuries.
Step-by-step explanation:
When performing CPR (cardiopulmonary resuscitation), we allow the chest to expand outward and contract inward to facilitate manual compression. This movement is essential for mimicking the heart's pumping action and maintaining blood circulation, especially to the brain where cells are quickly damaged by the lack of oxygen.
Current CPR guidelines emphasize the importance of high-quality chest compressions over artificial respiration, recommending a compression depth of at least 5 cm and a rate of 100 compressions per minute. This rate corresponds to the beat of the song "Staying Alive", which helps in achieving the appropriate rhythm. It's vital to position the hands on the sternum between T4 and T9 vertebrae, applying pressure to compress the heart effectively and increase the chance of survival until professional medical help arrives or the heart resumes independent beating.
However, incorrect technique can cause severe injuries such as broken ribs or sternum, highlighting the need for proper CPR training. Formal CPR certification is highly encouraged for medical personnel and the general public, with courses available through various organizations.