What is hypotension?
Hypotension is also known as low blood pressure and it occurs when blood pressure (BP), during and after each heartbeat is much lower than usual, so the heart, brain and other parts of the body do not get enough blood.
The blood pressure must be high enough to carry oxygen and nutrients to the body’s cells and extract the waste products from them.
When is low blood pressure?
It can be considered that BP is low when it is lower than 90/60 mmHg (millimeters of mercury). Although some people with a drop of 20 mmHg in their pressure, can cause them problems such as dizziness and fainting.
In general, normal blood pressure should be between 90/60 mmHg and 130/80 mmHg.
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What to do if you have low blood pressure?
If you have low blood pressure and do not have symptoms such as dizziness, vertigo or fainting, it means that it is not serious, so you can drink coffee with sugar or another drink with sugar to help level blood pressure or if you want, you can try some of the home remedies to raise the low pressure.
Although you have to keep in mind that for a frequent low BP, it may be best to consult your doctor.
If you have any type of symptoms such as dizziness or fainting, it is best to avoid places with high temperature, then as soon as possible lie down in a place where there is shade and raise your legs so that they are diagonally, helping you to hold your feet in a wall or any person who holds them for you, as you can see in the image below.
Types and causes of hypotension
To talk about the causes of hypotension we must first identify the types of low BP that exist and the proper causes for each of them, mainly there are three types of hypotension:
– Orthostatic hypotension:
Orthostatic hypotension is an excessive reduction of BP by adopting the vertical position, which causes a decrease in blood flow to the brain. This is caused by a sudden change in the position of the body, usually going from lying to standing and commonly lasting only a few seconds or minutes.
– Neurally mediated hypotension:
It most commonly affects young adults and children, and this occurs when a person has been standing for a long time. Normally, children overcome this type of hypotension over time.
– Severe hypotension:
It is usually caused by a sudden loss of blood (shock), infection, heart attack, or allergic reaction.
Some medications and substances that can cause your blood pressure goes down are:
- Certain antidepressants
- Vasodilator drugs (nitrates, calcium blockers, etc.)
- Medicines for the heart
- Drugs used for surgery
In addition to the causes mentioned above, there are other factors that can cause your blood pressure goes down, such as:
- Anaphylaxis (a life-threatening allergic reaction)
- Heart attack
- Changes in heart rhythm (arrhythmias)
- Advanced diabetes
- Pulmonary embolism
- Exposure to heat
- Heart failure
- Excessive urination
- Septic shock (caused by a serious infection, stroke, anaphylaxis, hemorrhage, or heart attack)
- Excessive sweating
- Valvular diseases
Symptoms of hypotension
Among symptoms of low pressure, we can find:
- Blurry vision
- Fainting (syncope) – (When the cause is an arrhythmia, fainting appears and disappears abruptly)
When the person is standing, light dizziness may be noticed prior to the fainting, and when the person falls to the floor, the blood pressure may increase in part because the person is lying down and often because the cause of the syncope has already passed. Although you have to be careful because getting up too quickly can cause a new fainting.
Certain times palpitations (perception of the heartbeat) can be experienced just before the fading.
The factors that facilitate the diagnosis are the age of onset of fainting episodes or other symptoms, the circumstances in which they occur, the warning signs before the episode and the maneuvers that help the person to recover (such as lying down, containing the breath, etc.).
The doctor also needs to know if the person has any other medical condition and if they are taking any drug, whether or not it is prescribed by a doctor.
In addition, some tests such as an electrocardiogram may indicate underlying heart or lung disease, as well as echocardiography (a technique that produces images using ultrasound), may reveal structural or functional cardiac abnormalities. On the other hand, blood tests can detect a low blood sugar concentration (hypoglycemia) or a reduced number of red blood cells (anemia).
Frequently it is enough to lie down to recover knowledge. Elevating the legs can speed recovery, as it increases the flow of blood to the heart and brain.
In young people who do not have heart disease, fainting is generally not serious and there is no need for extensive diagnostic tests or treatment. However, in older people, syncopes (fainting) can be caused by several interconnected problems that prevent the heart and blood vessels from reacting to a decrease in blood pressure.
The treatment depends on the cause. To correct a too slow heart rate, a pacemaker can be implanted surgically, consisting of an electronic device that stimulates the heartbeat. To slow a heart rate too fast, drugs can be used.
If the problem is an alteration of the rhythm (the heart beats irregularly from time to time), it can be resorted to the implantation of a defibrillator. Other causes of fainting (such as hypoglycemia, anemia, or low blood volume) can also be treated.
Surgical intervention should be considered when syncope is due to a valvular heart disease, regardless of the age of the person. When the cause of orthostatic hypotension is due to a decrease in blood volume, a particular medicine or a certain dose of a medication, the disorder can be corrected quickly. When there is no treatment for the cause of orthostatic hypotension, it is often possible to eliminate or reduce the symptoms. People prone to this condition should not stand up suddenly or stand still for a long time. If arterial hypotension is caused by blood accumulation in the legs, elastic compression stockings can be very useful.
To prevent a decrease in blood pressure, ephedrine or phenylephrine can be administered. If these treatments are not effective, other drugs (such as propranolol, dihydroergotamine, indomethacin and metoclopramide) can help prevent orthostatic hypotension, although with a high risk of side effects.