 |
| Hypotension |
Last updated: Jul 17, 2008 |
Signs, symptoms and indicators | Contributing risk factors | Recommendations
 |
|
 |
| |
Most physicians in the English-speaking world consider hypotension - low blood pressure - to be a symptom of some other disorder. In other parts of the world, however, hypotension is itself considered to be a disorder that can cause various symptoms, including depression, lethargy and fatigue. This different attitude is probably the result of different methods of medical training.
There are different kinds of hypotension and the following is one way of classifying them: - Constant Hypotension. The blood pressure is always low, less than 90/60 mmHg. When the blood pressure is too low there is inadequate blood flow to the heart, brain and other vital organs. Borderline low blood pressure for one person may be normal for another. Many people have a chronic problem with low blood pressure that is not particularly serious.
- Temporary Hypotension. The most important factor is how the blood pressure changes from the baseline or normal condition. A fall of 30 mmHg or more from a person’s baseline is considered low blood pressure. This can be caused by any of the following:
- Shock
- Stress/trauma
- Sudden change in posture (orthostatic hypotension)
- Allergy
- Dehydration
- Drug-induced, including alcohol toxicity, anesthesia, antianxiety agents, antihypertensives, calcium channel blockers, diuretics, general anesthetics, antiarrhythmics, monoamine oxidase inhibitors, narcotic analgesics, tranquilizers, vasodilators
- Neurally Mediated Hypotension (NMH). The usual blood pressure may be low, normal or even high, but under certain circumstances blood pressure drops and symptoms develop.
- Age-related decline in blood pressure regulation.
- Secondary to diseases such as central nervous system disorders, for example Shy-Drager syndrome; peripheral neuropathy and autonomic neuropathy (nerve problems), such as may be caused by diabetes mellitus; cardiovascular disorders; nutritional diseases amyloidosis; vitamin deficiencies; spinal cord injuries; Adrenal failure (Addisonian crisis); and neuropathies associated with cancer, particularly lung cancer or pancreatic cancer.
Postural hypotension can happen to anyone for a variety of physiologic reasons, such as dehydration, lack of food, prolonged standing in the heat or being generally run down. Postural hypotension occurs most frequently in people who are taking drugs to control high blood pressure (hypertension). It can also be related to pregnancy, strong emotion, atherosclerosis or diabetes. The elderly are particularly affected, especially those who have high blood pressure or autonomic nervous dysfunction. Postprandial (after meals) hypotension is estimated to affect up to one-third of elderly people and is a common cause of dizziness and falls after eating.
Neurally mediated hypotension is also known by the following names: the fainting reflex, neurocardiogenic syncope, vasodepressor syncope, the vaso-vagal reflex, and autonomic dysfunction. Neurally mediated hypotension occurs when there is an abnormal reflex interaction between the heart and the brain, both of which usually are structurally normal.
Neurally mediated hypotension occurs in susceptible individuals in the following settings:- after prolonged periods of quiet upright posture (such as standing in line, standing in a shower, or even sitting up for long periods),
- after being in a warm environment (such as in hot summer weather, a hot crowded -corn, a hot shower or bath),
immediately after exercise, - after emotionally stressful events, (seeing blood or gory scenes, being scared or anxious).
- some individuals get symptoms soon after eating, when blood flow has shifted to the intestinal circulation during the process of digestion.
We are all susceptible to activation of this vaso-vagal reflex that results in a lowered blood pressure (NMH), but each person's susceptibility is affected by their genetic make-up, dietary factors, psychological make-up, and acute triggers such as infection and allergy. The clinical problem of NMH occurs when there is sufficiently early triggering of this reflex to cause symptoms.
Diagnostic and Test Procedures Symptoms of dizziness and lightheadedness upon standing do not necessarily mean that you have postural hypotension. A wide range of underlying conditions may cause these symptoms. An accurate diagnosis must be based on repeated evaluation of blood pressure and pulse rate after you have been lying down for at least five minutes and then after you stand quietly for one minute and then for three minutes. A hypotensive response may be immediate or delayed. Prolonged standing or a tilt test may be needed to detect a delayed hypotensive response.
Treatment If you have an underlying medical problem that causes postural hypotension, seek treatment for the underlying condition. There is a spontaneous improvement in many individuals, although treatment of the cause helps the return to normal. For many people, chronic physiologic postural hypotension can be effectively treated with diet and lifestyle changes. Have your doctor evaluate your prescription and over-the-counter medications to identify any that may be causing your symptoms. Be careful when rising from a prone or sitting position. To improve circulation, stretch your feet back and forth before standing up. Then proceed slowly. When getting out of bed, sit upright on the edge of the bed for a few moments before standing.
|
|
 |
|
 |
Signs, symptoms & indicators of Hypotension: | |  | | | | Lab Values - Common | Low systolic blood pressure
Low diastolic blood pressure | Symptoms - General |
Dizziness when standing up |
| |  | |  |
Risk factors for Hypotension: | |  | | | | Immunity | Chronic Fatigue / Fibromyalgia Syndrome | Researchers at Johns Hopkins University in Baltimore, Maryland, have carried out the first study to show that CFS symptoms can be improved when treatment is aimed at neurally mediated hypotension, a blood pressure regulation disorder also called the fainting reflex. Peter Rowe, MD, is the pediatrician at Johns Hopkins who first made the link between CFS and neurally mediated hypotension. Hypotension is the medical term for low blood pressure. Neurally mediated hypotension occurs when there is abnormal reflex interaction between the heart and the brain. The condition can cause fainting, lightheadedness, headaches, mental confusion, and chronic fatigue.
Findings from the Hopkins study, which were published in the Journal of the American Medical Association, revealed that such symptoms cleared up after the neurally mediated hypotension was diagnosed and treated.
Twenty-two of 23 patients with CFS tested positive for neurally mediated hypotension. After treatment, nine patients reported almost complete recovery from fatigue, while others noted some level of improvement.
Neurally mediated hypotension cannot be detected through routine blood pressure testing, but rather through what's known as the Tilt Table Test. Each patient in the Hopkins study underwent the test, which is performed by having the patient lie down on a table. The table is then gradually raised to a near vertical position and the patient's blood pressure is monitored.
In a person without CFS, the blood pressure will not change much while on the table. But those who have CFS eventually experience a drop in blood pressure. The same change that occurs on the tilt table also occurs when the person stands up. Normally when we stand up we experience a surge of adrenalin that makes the heart beat faster, allowing the blood returning to our heart to be pumped more efficiently. But people with neurally mediated hypotension experience more pooling of blood in the legs which keeps blood away from the areas where it's needed. When blood pressure levels are inadequate and organs do not receive needed oxygen or nutrients, the result can be extreme fatigue and fainting.
If blood pressure is low in CFIDS / FMS, try Florinef, Prozac, Dexedrine, or ephedrine; and increase salt and water intake. |
| Lab Values - Common |
Having very/having low diastolic BP | Organ Health |
Pancreatitis |
| |  | |  |
Recommendations for Hypotension: | |  | | | | Botanical | Coffee (Coffea genus) | If tolerated, you may try drinking coffee in the morning. The amount of caffeine normally found in two cups of coffee (200mg) can decrease postural hypotension in young adults and can be safely used by older adults as well. |
Scots Broom (Cystisus Scoparius) | Scots Broom has a well-known effect of raising blood pressure because of a mild peripheral vaso-constricting action combined with a gentle cardiotonic effect. Thus it is strongly contra-indicated for hypertension.
One possible herbal prescription using up to 2.5ml of tincture tid is: 2 parts each of hawthorn and scots broom; 1 part each of gentian, rosemary and ginger. |
| Diet |
Increased Water Consumption | The first step in treating hypotension is generally to increase fluid intake. Patients who have discovered the importance of drinking fluids regularly throughout the day seem to do better than those who don't take this task seriously. Drink a minimum of eight glasses per day of non-alcoholic fluids. Sports drinks that are high in sodium and potassium are recommended, especially during exercise or in hot weather. |
Smaller, More Frequent Meals | As more blood is drawn to the digestive tract, less may be available for maintaining blood pressure. To avoid problems with low blood pressure which occurs after meals, try eating smaller, more frequent meals and resting after eating to lessen episodes of dizziness. Avoid taking hypotensive drugs before meals. |
| Drug |
Conventional Drugs / Information | If simple measures don't alleviate the problem, you may need conventional medication. Although a wide range of drugs (including phenylpropanolamine, ephedrine and the nonsteroidal antiinflammatory drugs indomethacin and ibuprofen) have been used to treat hypotension, many of them are not consistently effective.
The following medications have proven effective in treating postural hypotension: Fludrocortisone. Fludrocortisone is a mineralocorticosteroid that appears to be effective for most types of postural hypotension. It works by promoting sodium retention by the kidney, thereby causing fluid retention and some swelling, which is necessary to improve blood pressure. Its sparing effect on sodium is done at the expense of a concurrent loss of potassium. Therefore, when taking fludrocortisone, it's important to also take adequate amounts of potassium each day. Fludrocortisone has none of the anti-inflammatory properties of cortisone or prednisone and it is not a muscle-building agent.
Midodrine. Midodrine activates receptors on the arterioles and veins to produce an increase in blood pressure. Studies show that it is effective in improving standing blood pressure in those with postural hypotension related to nervous system dysfunction, such as in patients with Shy-Drager syndrome. |
| Habits |
Aerobic Exercise | Regular exercise to promote blood flow and regulation can improve low blood pressure. |
| Mineral |
Increased Salt Consumption | Consuming a diet higher in salt will sometimes help restore a more normal blood pressure. One of the most common - and treatable - problems identified in those with NMH (Neurally Mediated Hypotension) is a low dietary salt (sodium) intake. Salt helps us retain fluid in the blood vessels, and helps maintain a healthy blood pressure. Salt has received bad press in the last couple of decades because a high salt diet in some individuals with high or high-normal blood pressure can contribute to further elevations, and thereby to heart disease and stroke. This has led to general health recommendations to cut down on salt. As we are finding, this general recommendation isn’t right for all people.
Consume extra salt and drink more fluids during hot weather and while sick with a viral illness, such as a cold or the flu. |
| Physical Medicine |
Hydrotherapy | Heating the skin draws more blood to the surface and increases the risk of lowered blood pressure. Avoid prolonged exposure to hot water, such as hot showers and spas. If you get dizzy, sit down. It may be helpful to keep a chair or stool in the shower in case you need to sit; to help prevent injury, use a chair or stool that is specifically designed for showers or bath tubs. |
Physical Supports | If needed, use elastic support (compression) stockings that cover the calf and thigh. These may help restrict blood flow to the legs, thus keeping more blood in the upper body. |
|
| |  | |  |
KEY |  | Weak or unproven link |  |  | Strong or generally accepted link |  |  | Proven definite or direct link |  |  | May do some good |  |  | Likely to help |
|
 |