Premergency First Aid, CPR and AED Manual

5 Cardiovascular Emergencies, CPR and AED The vena cava is the main vein of the body. It carries blood to the heart from other veins in the body. The pulmonary artery sends blood to the lungs to expel carbon dioxide and obtain oxygen.

The pulmonary veins return oxygenated blood from the lungs to the heart. The heart then pumps oxygenated blood via the left ventricle through the aorta circulating oxygenated blood to the organs and tissues of the body. The constant flow of blood to the tissues of the body is called perfusion. As the heart pumps, it circulates blood throughout the body, using arteries to carry oxygenated blood from the lungs to the capillaries for tissue perfusion and using veins to bring back the blood with waste carbon dioxide. Good perfusion requires three primary parts: 1. The heart has to be working properly. 2. There has to be enough blood for the heart to pump. 3. The blood vessels (arteries, veins and capillaries) have to be the right size for the volume of blood.

The Human Heart

Pulmonary Artery Pulmonary Veins

Superior Vena Cava

Aorta

Left Ventricle Left Atrium

Right Ventricle Right Atrium

Coronary Artery

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