Which of the following is true about CPR compressions?
a. They circulate blood around the body.
b. They remove carbon dioxide from the lungs.
c. They fill the lungs with oxygen.
d. They should be avoided on patients with a pacemaker.
The Correct Answer and Explanation is:
Correct Answer: a. They circulate blood around the body.
Explanation:
Cardiopulmonary resuscitation (CPR) is a life-saving technique used in emergencies when someone’s breathing or heartbeat has stopped. The most critical component of CPR is chest compressions, which aim to manually pump blood throughout the body, especially to the brain and heart.
Why Option A is Correct:
Chest compressions simulate the pumping action of the heart. When you press on the chest, you squeeze the heart between the sternum and the spine, pushing blood out of the heart and into the arteries. When you release, the heart refills with blood. This process temporarily restores partial flow of oxygenated blood to vital organs, particularly the brain and coronary arteries. Without this circulation, brain cells can begin to die within 4–6 minutes due to lack of oxygen.
Why the Other Options Are Incorrect:
- Option B: “They remove carbon dioxide from the lungs.”
This is the job of ventilation, not compressions. Ventilations during CPR (via rescue breaths or bag-valve mask) help remove carbon dioxide and bring oxygen into the lungs, but compressions alone do not have this effect. - Option C: “They fill the lungs with oxygen.”
Again, this pertains to ventilation, not compressions. Only breaths deliver oxygen to the lungs. Compressions help circulate that oxygen once it’s already present in the bloodstream. - Option D: “They should be avoided on patients with a pacemaker.”
This is not true. CPR should be performed on a person in cardiac arrest, regardless of whether they have a pacemaker. A pacemaker does not ensure adequate heart function during a cardiac arrest, and delaying CPR in such situations can be fatal.
Conclusion:
Chest compressions are the most critical part of CPR because they circulate blood and sustain life until more advanced care is available. Therefore, option A is the correct answer.