Hypotension and shock are not synonymous. While shock is always associated with low BP, a previously hypertensive patient may be in shock despite BP being within normal limits. Hypotension may occur in the absence of shock. Many people who have low blood pressure (hypotension) are healthy and have no signs or symptoms related to lower than normal readings. But for others, low blood pressure can cause dizziness and fainting or indicate serious heart, endocrine or neurological disorders. Hypotension is a medical concern only if it causes signs and/or symptoms such as dizziness, fainting, or, in extreme cases, shock .
Shock is defined as the state of widespread serious reduction of tissue blood flow, which if prolonged leads to generalised reduction of cell functions. Postprandial hypotension can cause dizziness, light-headedness, faintness, and falls. If an older person experiences these symptoms after eating, doctors measure blood pressure before and after meals to determine if postprandial hypotension is the cause. Hypotensive drugs include blood pressure drugs, diuretics (water pills), heart medications (especially calcium antagonists- nifedipine Procardia, beta blockers-propranolol Inderal and others), depression medications (such as amitriptyline Elavil), and alcohol. For example, vital organs (particularly the brain) may be starved of oxygen and nutrients if the blood pressure is too low for that particular individual.
Low blood pressure is an abnormal condition in which a person's blood pressure (the pressure of the blood against the walls of the blood vessels during and after each beat of the heart) is much lower than usual. Just a few decades ago, doctors thought a blood pressure reading of 160/95 millimeters of mercury (mm Hg) was an acceptable target rate for most Americans. Hypotension, or low blood pressure, means that the pressure of blood circulating around the body is lower than normal, or lower than expected, given the environmental conditions. It may be caused by hypovolemia (a decreased amount of blood in the body), resulting from the excessive use of diuretics, vasodilators, or other types of drugs, dehydration, or prolonged bed rest. The disorder may be associated with Addison's disease, atherosclerosis (build-up of fatty deposits in the arteries), diabetes, and certain neurological disorders including Shy-Drager syndrome and other dysautonomias.
Orthostatic hypotension is particularly common among older people. Is more likely to occur in people who have high blood pressure or disorders that impair the brain centers controlling the autonomic nervous system (which regulates internal body processes). For example, it rises during physical exertion and drops in extreme heat. Hypotension, or low blood pressure, means that the pressure of blood circulating around the body is lower than normal, or lower than expected, given the environmental conditions. Neurologic conditions that can lead to low blood pressure include changing position from lying to more vertical (postural hypotension), stroke , shock, lightheadedness after urinating or defecating, Parkinson's disease, neuropathy and simply fright. For some people, walking after a meal helps improve blood flow, but blood pressure may fall when they stop walking.
Causes of Hypotension
The common Causes of Hypotension :
- Medications used for surgery
- Anti-anxiety agents
- Treatment for high blood pressure or coronary heart disease (CHD)
- Heart failure
- Involvement of the intermediolateral cell column with the loss of small sympathetic neurons has been observed in some patients.
- Heart attack
- Some antidepressants
- Narcotic analgesics
- Heart medicines
- Allergic reaction to certain drugs or chemicals
- Histopathologically, alpha-synuclein immunostaining demonstrates glial cytoplasmic inclusions.
- Addison's disease (where the adrenal glands fail to produce sufficient blood pressure-maintaining hormones).
Symptoms of Hypotension
Some are common Symptoms of Hypotension :
- Blurred vision
- Dizziness or lightheadedness
- Cold, clammy, pale skin
- Rapid, shallow breathing
- Feeling faint or weak
Treatment of Hypotension
Here is the list of the methods for treating Hypotension :
- Discontinue antihypertensive medications and other medications known to lower blood pressure, if feasible.
- Slowly and gradually performing positional changes, such as standing up.
- Other pharmacologic treatment options are directed toward symptomatic relief only (See Medication section below).
- Low blood pressure symptoms that do not go away very quickly upon sitting or lying down can be a medical emergency, and immediate medical attention is needed
- Stopping a medicine or changing the dose if the medicine is causing the hypotension.
- These garments drive blood from the legs to the heart and brain and help blood circulate through the body.
- Doctors traditionally have used the drug midodrine to raise standing blood pressure levels in people with orthostatic hypotension.