Why Is Blood Pressure Testing Important in Biology?
Blood pressure is simply the pressure of the blood within the arteries, and a blood pressure test is like any other diagnostic test that checks whether our blood pressure is high or low.
What Is Blood Pressure?
The heart pumps blood around our body to give it the needed energy and oxygen. As the blood moves around the body, it exerts pressure on the inner walls of the blood vessels. This pressure is our blood pressure.
The measurement of blood pressure is recorded by two numbers, systolic pressure and diastolic pressure. The first one is measured after the heart contracts and the second one is measured before the contraction. Systolic pressure is higher than diastolic pressure. If one’s blood pressure is too high, it puts extra strain on the arteries which may lead to a heart attack or stroke. The blood pressure cuff is used to measure the pressure. The advancement of high blood pressure is called hypertension and degradation of low blood pressure is known as hypotension.
What Is A Blood Pressure Test?
A blood pressure test is just a normal test like any other test to check whether our blood pressure is high or low. There are plenty of cases where there are no clear symptoms of blood pressure dysfunction. But, abnormal blood pressure usually results in fatal diseases like stroke, heart attack, etc. People with blood pressures less than 120/80 mm Hg should undergo a blood pressure test every two years. People with systolic blood pressure 120 mm Hg to 139 mm Hg, or diastolic blood pressure 80 mm Hg to 89 mm Hg should test their blood pressure every year without fail.
Blood Pressure Chart
Here are the three different charts for High Blood Pressure, Low Blood Pressure, and Normal Blood Pressure:
High Blood Pressure Range
Low Blood Pressure Range
Normal Blood Pressure Range
Approx. Ideal Blood Pressure Range According to Age:
Causes and Symptoms of Abnormal Blood Pressure
Both high and low blood pressure is injurious to health. There are plenty of causes of abnormal blood pressure. Let’s have a look at the causes and symptom of high and low blood pressure.
Causes of High Blood Pressure
A salt, fat, and/or cholesterol-rich diet
Chronic kidney and hormonal problems, diabetes, and high cholesterol
Family history of high blood pressure
Lack of physical activity
Ageing
Obesity
Some birth control medicines along with other medicines.
Excess stress.
Smoking or drinking too much alcohol.
Genetics
Sleep deprivation for a long time
Symptoms of High Blood Pressure
Severe headache.
Fatigue or confusion.
Vision problems.
Chest pain.
Breathing trouble
Irregular heartbeat.
Blood in the urine.
Hammering in the chest, neck, or ears
Causes of Low Blood Pressure
Pregnancy
Heart problems
Endocrine problems
Dehydration
Blood loss
Severe infection or septicemia
Severe allergic reaction
Lack of nutrients in the diet.
Symptoms of High Blood Pressure
Dizziness or light-headedness
Nausea
Fainting
Dehydration and unusual thirst
Lack of concentration
Blurred vision
Cold, clammy, pale skin
Rapid, shallow breathing
Fatigue
Depression
Diagnosis of Hypertension and Hypotension`
Hypertension and hypotension both can lead to several fatal diseases. Physicians take two or three blood pressure readings each at three or more separate appointments before diagnosing a person with high blood pressure. To confirm if one has hypertension the physician may recommend a whole day long monitoring test called ambulatory blood pressure monitoring. One may also be recommended to undergo some routine tests like a urine test, a cholesterol test, an electrocardiogram, and an echocardiogram also to check for more signs of heart disease.
Continuous changes in lifestyle can control hypertension. The changes are as follows:
Eating a heart-healthy less salty diet
Regular physical exercise
Maintain proper weight
Restricting the amount of tobacco and alcohol
In addition to these lifestyle changes, one has to take medication if it has been prescribed by the doctor.
Hypotension may also turn into a disaster if medical assistance is not taken in time. Some regular blood tests, echocardiogram (ECG), and Tilt table test can tell if you have low blood pressure or not. The treatment of Hypotension depends on the very cause. According to the patient’s age, health and the type of hypotension he/she has, one can apply any one of these:
Using more salt in the diet
Drinking plenty of water
Wearing compression stockings
Take medications as prescribed by the physician
The Procedure of Blood Pressure Test
Blood pressure can be monitored at home also. One just has to be still while the test is going on. The patient should be still. Smoking, drinking caffeinated beverages or exercise within 30 minutes is strictly prohibited before measuring blood pressure. One must empty his/her bladder and rest at least 5 minutes before measurements.
The patient should sit with his/her back straight and supported on a dining chair rather than a sofa. His/her feet should be flat on the floor and should be straight, not crossed. Patient’s arm should be supported on a flat surface with the upper arm at heart level. The bottom of the cuff is placed directly above the bend of the elbow.
The test should be done at the same time every day. It’s important to take the readings at the same time each day.
Multiple readings are taken and the results are recorded.
The measurements are not taken over clothes.
Blood Pressure Testing Devices
Blood pressure measurement devices are divided into five categories: manual sphygmomanometers, digital non-portable for the upper arm with automatic inflation, digital portable for the upper arm with automatic inflation, digital portable for wrist with automatic inflation, and digital portable for finger with automatic inflation. The blood pressure testing devices are as follows:
Digital, portable automated unit
Sphygmomanometer
Stethoscope
Why Blood Pressure Test Is Required?
A blood pressure test is a measurement to check for the ongoing health condition of a patient. High blood pressure or low blood pressure both can lead to severe health problems.
High blood pressure can cause:
Damage to our arteries: damaged and narrowed arteries, aneurysm
Damage to our heart: coronary artery disease, enlarged left heart, heart failure
Damage to our brain: Transient Ischemic Attack, stroke, dementia, mild cognitive impairment
Damage to our kidneys: kidney scarring or glomerulosclerosis, kidney failure.
Damage to our eyes: damage to our retina or retinopathy, fluid build-up under the retina or choroidopathy, nerve damage or optic neuropathy.
Low blood pressure can also lead to dizziness, blurred vision, fatigue, depression. So, to know the actual situation of our health and to save it from future hazards beforehand, a blood pressure test is required.
FAQs on Blood Pressure Test: Steps, Ranges & Diagnosis
1. What is blood pressure and why is it an important health indicator?
Blood pressure is the force exerted by circulating blood on the walls of the body's main blood vessels, the arteries. It is a vital health indicator because it reflects how hard the heart is working to pump blood. Consistently high or low readings can signal underlying health problems, making the blood pressure test a crucial tool for assessing cardiovascular risk.
2. What do the two numbers in a blood pressure reading, like 120/80 mmHg, represent?
The two numbers in a blood pressure reading represent two different pressures measured in millimetres of mercury (mmHg):
- Systolic Pressure (the top number): This measures the pressure in your arteries when your heart beats or contracts.
- Diastolic Pressure (the bottom number): This measures the pressure in your arteries when your heart is at rest between beats.
A reading of 120/80 mmHg is considered the normal range for a healthy adult.
3. How is blood pressure measured using a sphygmomanometer?
A blood pressure test using a sphygmomanometer involves several steps. First, an inflatable cuff is wrapped around the upper arm, level with the heart. The cuff is inflated to a pressure that temporarily stops blood flow in the brachial artery. A stethoscope is placed over the artery as the pressure is slowly released. The first sound of blood pulsing through marks the systolic pressure, and the point where the sound disappears marks the diastolic pressure.
4. What is the difference between hypertension and hypotension?
Hypertension and hypotension are two types of abnormal blood pressure:
- Hypertension is the medical term for high blood pressure, where the force of blood against the artery walls is consistently too high (e.g., above 140/90 mmHg). It increases the risk of stroke and heart disease.
- Hypotension is the medical term for low blood pressure, where the pressure is abnormally low (e.g., below 90/60 mmHg). It can cause symptoms like dizziness and fainting.
5. How does untreated high blood pressure (hypertension) affect the body over time?
Untreated hypertension can cause significant damage to the body. The constant high pressure forces the heart to work harder and can damage the delicate inner lining of the arteries. This can lead to serious long-term health problems, including:
- Heart attack or heart failure
- Stroke
- Kidney disease or failure
- Vision loss
- Aneurysms (weakened, bulging arteries)
6. Why is a blood pressure test typically performed on the upper arm?
The test is usually done on the upper arm because the major artery there, the brachial artery, is a direct extension of the aorta, the main artery from the heart. Measuring at this location, which can be easily positioned at the same level as the heart, provides a convenient and accurate reflection of the body's central blood pressure without requiring invasive methods.
7. How are blood pressure readings categorised, for example, is 140/90 mmHg considered high?
Yes, 140/90 mmHg is considered high. Blood pressure readings are generally categorised into four main groups to help assess risk:
- Normal: Less than 120/80 mmHg
- Elevated: Systolic between 120-129 and diastolic less than 80 mmHg
- Hypertension Stage 1: Systolic between 130-139 or diastolic between 80-89 mmHg
- Hypertension Stage 2: Systolic at least 140 or diastolic at least 90 mmHg
8. What factors can temporarily affect a blood pressure reading and lead to an inaccurate result?
Several factors can temporarily affect a blood pressure reading, so it's important to be relaxed and properly prepared for a test. Common factors include:
- Stress and anxiety (often called 'white coat hypertension').
- Recent physical activity or exercise.
- Consumption of caffeine or nicotine within 30 minutes of the test.
- An unsupported back or arm, or crossed legs during the measurement.
- A full bladder.
9. Does normal blood pressure change with age?
Yes, it is common for baseline blood pressure to increase slightly with age. This happens because arteries naturally tend to become stiffer and less flexible over time, which can increase resistance to blood flow. However, a significant rise in blood pressure is not a normal part of ageing and should be addressed, as it greatly increases the risk of cardiovascular diseases.
10. How does the human body naturally regulate its blood pressure?
The body maintains blood pressure homeostasis through a complex interplay of systems. The nervous system uses specialised sensors called baroreceptors in arteries to detect pressure changes and signal the heart to adjust its rate and force. Hormones like adrenaline can quickly raise pressure, while the kidneys play a long-term role by controlling blood volume through water retention and excretion.
