- What is low blood pressure?
- What are the causes of hypotension?
- Hypotension: what are the symptoms?
- How is hypotension diagnosed?
- What are the risk factors for hypotension?
- Hypotension: is it serious?
- What to do against hypotension?
- How to avoid orthostatic discomfort?
- When to take medication?
- What to do if a person has orthostatic discomfort?
What is low blood pressure?
“A low blood pressure is defined by a systolic blood pressure figure less than or equal to 80 mm Hg. It is often the sudden drop in blood pressure that explains the poor clinical tolerance, in particular when blood pressure drops going from a lying or sitting position to a standing position and the person feels unwell”, teaches Pr Alain Furber, former head of the cardiology department of the CHU d’Angers, and president of the French Federation of Cardiology (FFC). Low blood pressure is common especially in the elderly. “More than 30% of people over 75 have orthostatic arterial hypotension”, adds the cardiologist.
What are the causes of hypotension?
We distinguish several types of hypotension.
- I’orthostatic hypotension (HO) is defined by a drop in systolic blood pressure ≥ 20 mmHg and/or diastolic ≥ 10 mmHg within 3 minutes of going from a supine to a standing position.
- I’postprandial arterial hypotension is defined as the drop in systolic blood pressure > 20 mmHg within two hours after a meal. It is often associated with orthostatic hypotension because it has the same causes.
Low blood pressure can be primary or constitutional (people who have always ulow blood pressure). Most often it is secondary. “Arterial hypotension can be linked to hypovolaemia, i.e. a reduced blood volume (haemorrhage, dehydration, too strict a salt-free diet, etc.), be the complication of a heart attack, the most frequent cause being a heart failurepathologies of the autonomic nervous system (Parkinson’s disease, diabetes) or be linked to taking a certain number of drugs, the main ones being antihypertensives (especially diuretics), antidepressants, anxiolytics and neuroleptics”, says Professor Furber. Excessive alcohol consumption can also cause low blood pressure.
Hypotension: what are the symptoms?
THE common symptoms of low blood pressure include dizziness, a tendency to lose consciousness, significant asthenia (fatigue). Orthostatic arterial hypotension is manifested by a feeling of black veil before the eyes, a feeling of unease which can go as far as syncope (loss of consciousness) or palpitations when going from a sitting or lying position to a standing position.
How is hypotension diagnosed?
“For diagnose hypertensionblood pressure is measured in a supine or sitting position, then after a quick rise blood pressure is measured in a standing position at 1, 2 and 3 minutes, and up to 5 to 10 minutes in a symptomatic patient, in order to detect late-onset orthostatic hypotensiondescribes Professor Alain Furber. A 24-hour ambulatory blood pressure measurement (ABPM) is performed in people who complain of fatigue without symptoms suggestive of orthostatic hypotension, looking for arterial hypotension. says this specialist.
What are the risk factors for hypotension?
Low blood pressure often affects the elderly, and begins at age 60. “These combine two factors of arterial hypotension: with age the baro-receptors are less effective in regulating blood pressure and they take several drugs, often including antidepressants or antihypertensives”, explains Professor Alain Furber. It is also common in people with diabetes or suffering from Parkinson’s disease or chronic kidney failure.
Hypotension: is it serious?
“In terms of risk, arterial hypotension, in particular orthostatic hypotension, is a risk factor for falls with fracture, in particular of the neck of the femur in the elderly, with the complications that these entail, informs Professor Furber. Poorly managed, low blood pressure increases dependence (because people are afraid to get up for fear of feeling unwell) which can lead to a loss of autonomy”, he specifies.
Low blood pressure also increases the risk of stroke. “This is why it is important that this pathology be detected and taken care of very early”, alert the doctor.
What to do against hypotension?
The management of orthostatic hypotension is based on hygiene measures:
- “not following a strict salt-free diet,
- regularly drink at least 1.5 to 2 liters of water a day,
- wear compression stockings in case of venous insufficiency (which worsens hypotension)
- stop alcohol consumption if necessary”, lists Professor Furber.
It is also recommended toavoid prolonged hot showers while standing and overall heat exposure.
In case of post-prandial arterial hypotension, the splitting of meals is advised, a short nap is also beneficial.
If these systematic measures are not sufficient, the next step is to act on the medications taken. “Antihypertensive drugs that will cause hypotension such as diuretics will be avoided. We may also have to reduce the doses of antihypertensive drugs and, in the most severe forms of hypotension, to give antihypertensive treatment only in the evening so that it has less effect during the day. In the elderly, no more than 3 therapeutic classes are accepted and these drugs must not cause orthostatic hypotension”informs Professor Furber.
How to avoid orthostatic discomfort?
The management of arterial hypotension also requires education of the person with orthostatic hypotension and who must know the circumstances triggering hypotension and implement strategies. “Thus, in the context of orthostatic hypotension, when first getting up in the morning, it is advisable to sit on the edge of the bed with your legs dangling for a few minutes before getting up. Before getting up after having been in a sitting position for a long time, it is recommended to cross your legs several times before getting up. Regular physical activity also improves orthostatic hypotension”, teaches Professor Furber.
When to take medication?
Medications are rarely prescribed for orthostatic hypotension. One molecule, midodine (Gutron), is used to treat low blood pressure severe orthostatic which occurs in particular in the context of degenerative neurological diseases. “It is prescribed especially in the case of particular forms of arterial hypotension in younger people. Corticosteroids (fludrocortisone) can be prescribed if necessary”, informs Professor Furber.
What to do if a person has orthostatic discomfort?
The course of action for orthostatic discomfort or vagal discomfort is similar. “The person should be lying down. If she has consciousness disorders, her legs should be raised to promote venous return,” says Professor Furber.
Sources:
- Interview Pr Alain Furber, former head of the cardiology department of the CHU d’Angers, and president of the French Federation of Cardiology (FFC)
- Roukain, A., Pechère-Bertschi, A. (2018). ‘Arterial hypotension: behind the scenes’, Rev Med Switzerland 2018; volume 4. no. 618, 1581 – 1587
- Management of orthostatic hypotension, expert consensus SFHTA SFGG EFAS, December 2014
- J.-L. Elghozi, J.-M. Sénard, Management of orthostatic hypotension, AMC pratique „ n°232 „ November 2014
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