PADI RTO First Aid Student Manual

How many litres of blood are there in an average-sized adult body? An average-sized adult body contains approximately six litres of blood liquid and blood solids. Liquids make up 55% and solids the remaining 45%, including red blood cells, white blood cells and platelets. Blood transports oxygen, nutrients, carbon dioxide and waste products. Blood also defends us against disease and helps regulate body temperature. How big is the heart, what is its general shape and where is it located? The heart is pear-shaped in size, it is a muscular organ hardly bigger than your fist. Your heart does approximately 70 beats/minute = 2.5 billion beats/lifetime. The heart is located in the chest cavity, behind the breast-bone and between the lungs. The right side pumps blood to the lungs and the left side pumps blood to other body parts. What is the name of the heart cells that trigger its beating action? Pacemaker cells initiate a chain reaction that causes the heart to contract in waves; they are located in the top right portion of the heart. The top cells contract first, followed by the lower portion of the heart. If pacemaker cells are deprived of oxygen, abnormal rhythm (ventricular fibrillation) may occur. What is the name of the blood vessels that take blood away from the heart? During each heart contraction, blood surges into the arteries – the vessels that carry blood away from the heart. Arteries are strong and elastic. What is a pulse and blood pressure? As blood enters an artery after the heart contracts, it stretches. This stretching can actually be felt when an artery is near the surface of the skin. This feeling of the stretching of arteries is called a pulse. Contraction of the heart propels the blood through the arteries with considerable force. This force is called blood pressure. When an artery is cut, blood spurts out under pressure in regular intervals. Typically, arterial blood is bright red because it is oxygen-rich. What is the name of the one cell wide blood vessels located at the site of nutrient and waste exchange? As blood moves away from the heart through the arteries, the vessels get smaller and smaller. Eventually the arteries branch into a network of tiny vessels called capillaries. All the body’s cells are in close proximity to a capillary network. This close association between capillaries and cells allows for the exchange of materials. Since capillary walls are only one cell thick, gases and nutrients can easily diffuse into and out of the thin walls.   A small cut or abrasion anywhere on the skin is sure to damage a bed of capillaries. When capillaries are cut, the blood oozes slowly and typically stops quickly due to clotting. What is the name of the blood vessels that take blood to the heart? As the blood flows out of the capillaries on their way back to the heart the network forms larger vessels called veins. Veins return blood to the heart. When a vein is cut the blood flows from the wound steadily without rhythmic spurts. Typically, the blood from veins is dark red because it is oxygen poor.

What is the name of the artery in the neck and wrist? Several arteries in the human body are important for Emergency Responders to know about. The carotid artery on each side of the neck is very close to the skin and typically easy to locate; it is a powerful artery since it is close to the heart, taking oxygen-rich blood to the brain. The radial artery near the wrist may be used to feel for a pulse. However, as you’ll learn, a casualty may not have a detectable carotid or radial artery pulse, but may still have a heartbeat. Feeling for a pulse may not be the best way to determine if a casualty has a heartbeat. During Skills Development you’ll learn the technique of quickly scanning the patient for responsiveness and normal breathing. Where are the artery pressure points on the leg and arm used to control severe bleeding? The two main pressure points can be found in the arms (this is the brachial artery that can be found by placing several fingers under the upper arm, several inches down from the armpit, then pressing inward until you feel a pulse) and the legs (this is the femoral artery that can be found on the inside of the thigh near the area of the groin). What arteries supply blood to the heart muscle? Coronary arteries supply blood directly to the heart. Heart attacks and cardiac arrest are two major problems. The lymphatic ystem

HLTAID002 - PROVIDE BASIC EMERGENCY LIFE SUPPORT

HLTAID002 - PROVIDE BASIC EMERGENCY LIFE SUPPORT

What are the two primary purposes of the lymphatic system? Like the cardiovascular system, the lymphatic system forms a vast network of vessels and is part of the body’s circulatory system. The two primary purposes of the lymphatic system are to transport returning fluids that have collected in tissues to the bloodstream and to filter out foreign particles, microorganisms and other tissue debris from the body. What are problems related to the lymphatic system? An injury to the abdomen may cause life- threatening internal bleeding from the spleen. Since a person with an infection may have inflamed, swollen and tender lymph nodes, you should be on the lookout for these indications during injury or illness assessment. The lymphatic system also removes injected venoms following a bite or sting from poisonous animals. Slowing the movement of lymph may reduce the spreading of venom from a poisonous bite or sting. As with any serious injury or illness, you provide initial care for the patient by alerting Emergency Medical Services.

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PADI RTO

PADI RTO