Chest compressions are important because they take over the work of the heart during cardiac arrest, pushing blood to the brain and other vital organs until the heart can (hopefully) be restarted.

What chest compressions actually do

When the heart stops, blood flow to the brain and heart drops to nearly zero within seconds. Chest compressions squeeze the heart between the sternum and spine and increase pressure inside the chest, forcing blood out into the arteries, then allowing the chest to recoil so blood can refill the heart. This artificial circulation helps keep brain cells and heart muscle alive long enough for defibrillation and advanced care to work.

Why they are the “main event” in CPR

Modern CPR guidelines put compressions first (the “C” in CAB: Compressions–Airway–Breathing) because good, continuous compressions are the single most critical factor in survival from cardiac arrest. Studies show that higher-quality, minimally interrupted chest compressions are directly linked to better chances of return of spontaneous circulation (ROSC) and better neurological outcomes. Even professional rescuers are now taught to prioritize staying “hard and fast” on the chest over doing too many other procedures that might interrupt compressions.

Key reasons chest compressions matter so much:

  • They maintain blood flow to the brain and heart, delaying irreversible damage.
  • They build and maintain coronary perfusion pressure (blood flow to the heart muscle), a major determinant of whether the heart can restart.
  • If they are stopped, perfusion pressure quickly falls, and survival chances drop; it takes several compressions to build that pressure back up again.

Why uninterrupted compressions are emphasized

Research on “continuous” or minimally interrupted CPR shows:

  • Longer stretches of uninterrupted compressions are associated with higher survival and better brain function in out-of-hospital cardiac arrest.
  • Frequent pauses (for checking a pulse, prolonged ventilations, or delayed defibrillation) reduce the effectiveness of CPR by allowing blood pressure to fall.
  • Newer protocols stress minimizing “hands-off” time before and after shocks so that compression time is maximized.

This is why many public campaigns teach hands‑only CPR for untrained bystanders: it is far better to provide continuous chest compressions than to do nothing while worrying about rescue breaths.

Simple way to picture it

You can think of chest compressions as a manual pump keeping a house’s plumbing barely running during a power outage. If you keep pumping steadily, enough water (blood) reaches the most important rooms (brain and heart) to prevent permanent damage until the power (the heart’s own rhythm) can come back on. Stop pumping for too long, and the system depressurizes, making it much harder to restart.

Bottom line: Chest compressions are important because they keep oxygenated blood moving when the heart has stopped, buying crucial minutes that can mean the difference between full recovery, severe brain injury, or death.

Information gathered from public forums or data available on the internet and portrayed here.