Monitoring the cardiovascular system

• Blood pressure is the measure of the pressure that the blood exerts against the walls of major arteries. 
• It is measured by a machine called a Sphygmomameter.
• It is measured in mmHg, also known as millimetres of mercury, as it is based on an old method when the manometer was made full of mercury. It is now replaced by a safer electronic version, the sphygmomameter. 

• The patient must be sat down, with their feet flat on the floor, breathing normally and not talking (as they would be controlling their breathing).
• The cuff is wrapped around the upper arm, approximately 2-3cm above the elbow.
• The cuff is then inflated until the brachial artery, which delivers blood to the arm, is squashed and blood can no longer flow through. The sensor which is within the cuff detects when the blood flow has stopped and the cuff stops inflating. 
• Air is then released from the cuff to reduce the pressure that is on the artery, so blood is now able to flow. With every heart contraction there is a surge of pressure through the artery, and when the cuff is the same pressure as the surge in blood, the artery opens and blood passes through. The senspr is able to detect this and is recorded as the systolic pressure. 
• The cuff continues to deflate. When the pressure is low enough for the artery to remain open, the diastolic pressure is recorded. 
• Results are then immediately available. 

                                                              125/80 

• This number is known as the systolic pressure, this is when the heart is contracting, it is ALWAYS HIGHER.
• This number is known as the diastolic pressure, this is when the heart is relaxed, it is ALWAYS LOWER.

Normal Pressures

• For a 20 year old male the normal pressure is 125/80, and for a 40 year old male the normal pressure is 135/80.
• For a 20 year old female the normal pressure is 123/80, and for a 40 year old female the normal pressure is 133/80. 
• What we can see from the results is males have higher systolic pressure than females, and as age increases, so does blood pressure. This is because arteries harden and there is an increase in fatty deposits.
• averages are worked out by doing systolic and diastolic pressure separately.

• High blood pressure can be because of, and lead to; angina, stoke, heart attacks, and kidney damage.
• Low blood pressure can be because of, but not limited to; dizziness, fainting and anoxia.
• Other non medical reasons for high or low blood pressure can be;
• hypertension - permanent high blood pressure. 
• hypotension - permanent low blood pressure. 
• raise temporarily - caffeine, exercise, smoking and anxiety.
• lower temporarily - dehydration, anaemia and blood loss.

For problems that only occur at certain intervals, an abulatory blood pressure test can be taken. This is a machine that a patient wears for 24 hours and their blood pressure is taken at random points,