2-2 Introduction to the Respiratory System Flashcards
Describe the main structure of the respiratory system
Upper airway: * Mouth * Nose larynx * Trachea Lower airway: * Lungs * Bronchi * Alveoli * Trachea
Define respiration
Respiration is the process of breathing air (inspiration) containing oxygen (O2). O2 is then transferred into the blood at the alveoli by a process called gas exchange where it is delivered to the bodily tissues by the cardiovascular system. The waste product of respiration is carbon dioxide (CO2). This is returned to the lungs via the cardiovascular system to be breathed out as waste (expiration).
Describe the mechanics of inspiration
When inspiring, the intercostal muscles contact and pull the ribs upwards and outwards. Air flow is then induced when respiratory muscles create a vacuum in the chest. The dome shaped diaphragm contacts and flats, increasing volume of chest and the lungs expand.
Describe the mechanics of expiration
When expiring, intercostal muscles relax and return to their normal position. Air flow is produced as the chest relaxes and returns to its normal position. The dome-shaped diaphragm relaxes and moves upwards returning to it normal shape and the lungs then recoil.
Describe what to look for when checking a casualties breathing
When assessing a casualties breathing, check the rate and listen for any breathing difficulties or unusual noises. The normal breathing rate for an adult is 12-20 breaths per minute. In babies and younger children, a normal breathing rate of 20-40 breaths per minute is expected depending on their age. Commonly, the younger they are, the faster their breathing rate. When checking breathing, LOOK, LISTEN,FEEL for no longer that 10 seconds
Describe the circulatory system
The heart and the blood vessels make up the circulatory system. These structures supply the body with a constant flow of blood, which brings oxygen and nutrients to the tissues and carries the waste away.
Describe the function of the heart
The heart is a hollow muscular pump which pumps blood around the body. The heart has four main chamber:
* Right atrium
* Right ventricle
* Left atrium
* Left ventricle
The hearts right side pumps deoxygenated blood from the body to the lungs and the left side of the heart pumps oxygenated blood to the rest of the body via the aorta.
Describe the journey of oxygenated blood
Oxygenated blood from the lungs is pumped into the left aorta and through the mitral valve into the left ventricle. Its is then pumped through the aortic valve into the body where it will supply the body with oxygenated blood.
Describe the journey of deoxygenated blood
Deoxygenated blood is pumped from the body and into the right aorta. it is then pumped through the tricuspid valve into the aortic valve. It is then pumped through the pulmonary valve and through to lungs where the blood will then be oxygenated.
Describe the pulse
Each heartbeat creates a wave of pressure as blood is pumped along the arteries. A pulse is felt by depressing an artery against an underlying firm structure. Common pulses checked are the radial pulse and carotid pulse. A normal pulse rate in an adult will be around 60-80bpm but may be slower in very fit adults. A Childs pulse rate will be faster.
Describe an artery
An artery has thick muscular walls that will expand each time the heart beats. Arteries carry oxygenated blood away from the heart
Describe a vein
A vein has thin muscular walls. They have cup like valves that prevent a back flow of blood. Veins carry de-oxygenated blood back to the heart. Muscle movement, position and breathing all assist with blood return to the heart.
Describe a capillary
Capillaries are a network of fine blood vessels. They are one cell thick and they link arteries and veins within body tissues. They allow oxygen and nutrients to pass from the blood into the tissue and waste products to pass from the tissue into the blood.
