What is hypotension?
Hypotension is abnormally low blood pressure (lower than 90/60 mm Hg). If your blood pressure gets too low, it can cause dizziness, fainting or death.
Low blood pressure is not a condition that is usually treated except if it occurs in the elderly or occurs suddenly. In patients over 65, it could indicate the brain and limbs are not receiving adequate blood supply. If your blood pressure drops suddenly, it could deprive the brain of blood, which can lead to lightheadedness or dizziness.
When blood pressure drops suddenly after moving from a lying down to a sitting position, it is called postural hypotension or orthostatic hypotension.
When blood pressure drops from standing for a long period of time and leads to passing out, it is called vasovagal syncope.
Causes of hypotension
There are several causes of hypotension including:
- Prolonged bed rest
- Low or high body temperature
- Excessive blood loss
- Severe dehydration
- Blood infections such as sepsis
- Anaphylaxis allergic reaction
- Reactions to medication or alcohol
Risk factors for hypotension
- Age — your risk of low pressure increases as you age. Approximately 10-20% of people older than 65 have postural hypotension.
- Medications — medications, such as alpha blockers, can lower blood pressure.
- Other serious conditions — if you have diabetes or Parkinson’s disease, you have a higher risk for developing hypotension.
Symptoms of hypotension
Most doctors don’t consider hypotension serious unless it produces noticeable symptoms such as:
- Blurred vision
- Cold, clammy, pale skin
If you have cold, clammy or pale skin, rapid or shallow breathing, weak or rapid pulse or confusion, you could be suffering from extreme hypotension, which could lead to death. Call 911 immediately if you suspect you are suffering from extreme hypotension.
Diagnosis of hypotension
One abnormally low blood pressure reading without any other symptoms will usually not cause concern. In most cases, your doctor will monitor you over a series of visits to evaluate if the low blood pressure is a consistent pattern. The physician may also order other diagnostic tests to determine the underlying cause of the condition.
Tests that your doctor may order include:
- Blood tests — can help you determine if you have hypoglycemia (low blood sugar), hyperglycemia/diabetes (high blood sugar) or anemia (low red blood count).
- Electrocardiogram (ECG) — can detect the heart’s electrical signals to detect heart rhythm or structural abnormalities, as well as problems with the supply of oxygen-rich blood to the heart.
- Echocardiogram — can show detailed images of the heart to determine structure and function.
- Stress test — during a stress test, you will do some form of exercise to get your heart pumping faster and then you will be monitored with an echocardiogram or electrocardiogram.
- Tilt table test — will determine how your body reacts to changes in position; you will lie on a table that is then tilted to simulate moving from a lying to standing position.
Treatments of hypotension
Low blood pressure that doesn’t show any symptoms does not typically require treatment. For those who do have symptoms, you will be treated based on what the underlying cause of the low blood pressure is.
Home treatments include:
- Increasing water consumption and limiting alcohol consumption — water helps increase blood volume and prevent dehydration.
- Wearing compression socks — wearing compression socks promotes blood flow in the legs.
- Consuming more salt — sodium makes it harder for your body to rid itself of excess fluid and adds strain to the blood vessels resulting in raised blood pressure.
- Exercising regularly — regular exercise promotes blood flow.
If conservative treatments are not successful in increasing your blood pressure, your doctor may need to prescribe medication.
Drugs that treat hypotension include:
- Fludrocortisone — a drug which helps the body retain sodium in the kidney, which helps raise blood pressure.
- Midodrine — a drug that can increase blood pressure by activating receptors on the small arteries and veins.