The Circulatory System:
The circultory system consists of the the heart, arteries and veins this is how the blood is carried throughout the body.. Blood is pumped from the heart and carried in a high pressure system though the large arteries which branch into smaller ones (arterioles) to a set of very fine, thin-walled capillaries.A gas and chemical exchange happens between the blood and the tissue field, Oxygen and other nutrients are supplied and carbon dioxide and other waste products (venules) and returns to the heart in the low pressure system of veins.
Pressure receptors maintain a vital flow of blood to vital organs such as the brain and kidneys, the pressure receptors adjust the heart rate and the contraction of the arteries by chemical control.
Disorders of the circulatory system,
Atheroma is the main cause of degenerative conditions of the heart. This is the most common causes of problems in the heart these are causes by changes in the arteries.which restrict the flow of blood.
If atheroma occurs in the heart or brain it can lead to strokes and heart attacks when there is a shortage or blockage of blood flow:or angina, dizziness, disturbances of vision and collapse when the blockage is small or partial. Try not to smoke as it only aggravates the condition.
Gangrene can start in the feet when the leg arteries when severe atheroma is present. This reduces the circulation around the circulatory system.
Bacteria nd viruses can interfere with the blood stream leading to obstruction of the blood flow.
In some cases the heart beat can be very fast this may be caused by a congenital heart defect at birth. In adults it can be a deterioration in the nerves controlling heart beat and/or blood flow.
Heart rate and rhythm are also very sensitive in the chemical state of the blood, for example the concentration of oxygen, carbon dioxide, potassium, sodium and calcium.
General diseases can affect the heart muscle. The heart and circulation also respond to emotional changes such as anxiety and fear.
High risk groups,
- Babies Any drug taken by pregnant wmen even aspirin, smoking and certain diseases such as german measles are related and can contribute to congenital abnormalities of the heart.
- Smokers. Smoking goes without saying is known to have harmful effects on arteries both within the heart and general cirxculation.
- The middle aged and elderly. The heart may be affected by disease elsewhere in the body. Serious lung disease, such as chronic bronhitis and obstructive pulmonary or airways disease, which strains the heart
Emergencies
Proffesional care is vital in emergencies of the heart and circulation, but first aid can be applied until help arrives.
- Seat people who are short of breath or are in pain,
- Lie unconscious patients who are breathing on their sides.
- Calmly relax a patient who is in pain and ask them to chew an aspirin if available this can stimulate the healing process.
- Make the patient a Cup of Tea or Glass of Water, in some countries the patient biting on a Tea bag helps with breathing problems.
- Apply heart massage if the patient is not breathing or unconscious the old method was breathing in the mouth with the tongue held down, it's best to gently press around the chest gently but firmly with the back of the thumb. St John Ambulance
