Deep Vein Thrombosis (DVT, Blood Clot in the Legs)

Deep vein thrombosis (DVT)

Arteries have thin muscles within their walls to be able to withstand the pressure of the heart pumping blood to the far reaches of the body. Veins don't have a significant muscle lining, and there is nothing pumping blood back to the heart except physiology. Blood returns to the heart because the body's large muscles squeeze the veins as they contract in their normal activity of moving the body. The normal activities of moving the body returns the blood back to the heart.

 

There are two types of veins in the leg; superficial veins and deep veins. Superficial veins lie just below the skin and are easily seen on the surface. Deep veins, as their name implies, are located deep within the muscles of the leg. Blood flows from the superficial veins into the deep venous system through small perforator veins. Superficial and perforator veins have one-way valves within them that allow blood to flow only in the direction of the heart when the veins are squeezed.
A blood clot (thrombus) in the deep venous system of the leg is not dangerous in itself. The situation becomes life-threatening when a piece of the blood clot breaks off (embolus, pleural=emboli), travels downstream through the heart into the pulmonary circulation system, and becomes lodged in the lung. Diagnosis and treatment of a deep venous thrombosis (DVT) is meant to prevent pulmonary embolism.
Clots in the superficial veins do not pose a danger of causing pulmonary emboli because the perforator vein valves act as a sieve to prevent clots from entering the deep venous system. They are usually not at risk of causing pulmonary embolism.

Causes

 

Blood is meant to flow; if it becomes stagnant there is a potential for it to clot. The blood in veins is constantly forming microscopic clots that are routinely broken down by the body. If the balance of clot formation and resolution is altered, significant clotting can occur.

 

A thrombus can form if one, or a combination of the following situations is present.

Immobility

• Prolonged travel and sitting, such as long airplane flights ("economy class syndrome"), car, or train travel
• Hospitalization
• Surgery
• Trauma to the lower leg with or without surgery or casting
• Pregnancy, including 6-8 weeks post partum
• Obesity

Hypercoagulability (coagulation of blood faster than usual)

• Medications (for example, birth control pills, estrogen)
• Smoking
• Genetic predisposition
• Polycythemia (increased number of red blood cells)
• Cancer

Trauma to the vein

• Fracture to the leg
• Bruised leg
• Complication of an invasive procedure of the vein

Symptoms

Superficial thrombophlebitis
Blood clots in the superficial vein system most often occur due to trauma to the vein which causes a small blood clot to form. Inflammation of the vein and surrounding skin causes the symptoms of any other type of inflammation including:

• redness,
• warmth,
• tenderness, and
• swelling.

Often the affected vein can be palpated (felt) as a firm, thickened cord. There may be inflammation that follows the course of part of the vein.
Although there is inflammation, there is no infection.
Varicosities can predispose to superficial thrombophlebitis. When the valves of the larger veins in the superficial system fail (the greater and lesser saphenous veins), blood can back up and cause the veins to swell and become distorted or tortuous. The valves fail when veins lose their elasticity and stretch. This can be due to age, prolonged standing, obesity, pregnancy, and genetic factors.

Deep Venous Thrombosis

The symptoms of deep vein thrombosis are related to obstruction of blood returning to the heart and causing a backup of blood in the leg. Classically, they symptoms include:

• pain,
• swelling,
• warmth, and
• redness.

Not all of these symptoms have to occur; one, all, or none may be present with a deep vein thrombosis. The symptoms may mimic an infection or cellulitis of the leg.
Historically, healthcare providers would try to elicit a couple of clinical findings to make a diagnosis. Dorsiflexion of the foot (pulling the toes towards the nose, or Homans' sign) and Pratt's sign (squeezing the calf to produce pain), have not been found effective in making a diagnosis.

Medical care

The diagnosis of a superficial or deep thrombosis often relies on the clinical skill of the health care practitioner. Diagnostic tests need to be tailored to each situation.
Leg swelling, redness, and pain may be indicators of a blood clot and should not be ignored. These symptoms may be due to other causes (for example, cellulitis or infection), but it may be difficult to make the diagnosis without seeking medical advice.
If there is associated chest pain or shortness of breath, then further concern exists that a pulmonary embolus may be the cause. Once again, seeking immediate advice is appropriate.

Diagnosis

The diagnosis of superficial thrombophlebitis is made clinically.
Ultrasound is now the standard method of diagnosing the presence of a deep vein thrombosis. The ultrasound technician may be able to determine whether a clot exists, where it is located in the leg, and how large it is. Ultrasounds can be compared over time to see whether a clot has grown or resolved. Ultrasound is better at "seeing" veins above the knee as compared to the veins below it.
Venography, injecting dye into the veins to look for a thrombus, is not usually performed any more and has become more of a historical footnote.
D-dimer is a blood test that may be used as a screening test to determine if a blood clot exists. D-dimer is a chemical that is produced when a blood clot in the body gradually dissolves. The test is used as a positive or negative indicator. If the result is negative, then no blood clot exists. If the D-dimer test is positive, it does not necessarily mean that a deep vein thrombosis is present since many situations will have an expected positive result (for example, from surgery, a fall, or pregnancy). For that reason, D-dimer testing must be used selectively.
Other blood testing may be considered based on the potential cause for the deep vein thrombosis.

Treatment

Superficial Thrombophlebitis
Treatment for superficial blood clots is symptomatic with:

• warm compresses,
• leg compression, and
• an anti-inflammatory medications such as ibuprofen.

If the thrombophlebitis occurs near the groin where the superficial and deep systems join together, there is potential that the thrombus could extend into the deep venous system. These patients may require anticoagulation or blood thinning therapy (see below).

Deep venous thromboses

Deep venous thromboses that occur below the knee tend not to embolize (break loose). They may be observed with serial ultrasounds to make certain they are not extending above the knee. At the same time, the cause of the deep vein thrombosis may need to be addressed.
The treatment for deep venous thrombosis above the knee is anticoagulation, unless a contraindication exists. Contraindications include recent major surgery (since anticoagulation would thin all the blood in the body, not just that in the leg, leading to significant bleeding issues), or abnormal reactions when previously exposed to blood thinner medications.
Anticoagulation prevents further growth of the blood clot and prevents it from forming an embolus that can travel to the lung.
Anticoagulation is a two step process. Warfarin (Coumadin) is the drug of choice for anti-coagulation. It is begun immediately, but unfortunately it may take a week or more for the blood to be appropriately thinned. Therefore, low molecular weight heparin [enoxaparin (Lovenox)] is administered at the same time. It thins the blood via a different mechanism and is used as a bridge therapy until the warfarin has reached its therapeutic level. Enoxaparin injections can be given on an outpatient basis.
For those patients who have contraindications to the use of enoxaparin (for example, kidney failure does not allow the drug to be metabolized), intravenous heparin can be used as the first step. This requires admission to the hospital.
The dosage of warfarin is monitored by blood tests measuring the prothrombin time or INR (international normalized ratio). For an uncomplicated deep vein thrombosis, the recommended length of therapy with warfarin is three to six months.
Some patients may have contraindications for warfarin therapy, for example a patient with bleeding in the brain, major trauma, or recent significant surgery. An alternative may be to place a filter in the inferior vena cava (the major vein that collects blood from both legs) to prevent emboli from reaching the heart and lungs. These filters may be effective but also may be the source of new clot formation.

Surgery

Surgery is a rare option in treating large deep venous thrombosis of the leg in patients who cannot take blood thinners or who have developed recurrent blood clots while on anti-coagulant medications. The surgery is usually accompanied by placing an IVC (inferior vena cava) filter to prevent future clots from embolizing to the lung.
Phlegmasia Cerulea Dolens describes a situation in which a blood clot forms in the iliac vein of the pelvis and the femoral vein of the leg, obstructing almost all blood return and compromising blood supply to the leg. In this case surgery may be considered to remove the clot, but the patient will also require anti-coagulant medications.

Complications

Pulmonary embolism is the major complication of deep vein thrombosis. It can present with chest pain and shortness of breath and is a life-threatening condition. More than 90% of pulmonary emboli arise from the legs.
Post-phlebitic syndrome can occur after a deep vein thrombosis. The affected leg can become chronically swollen and painful with skin color changes and ulcer formation around the foot and ankle.

Prevention

As is the case with most medical illnesses, prevention is of prime importance. Minimizing risk factors is key to deep vein thrombosis prevention.
In the hospital setting, the staff works hard to minimize the potential for clot formation in immobilized patients. Compression stockings are routinely used. Surgery patients are out of bed walking (ambulatory) earlier and low dose heparin or enoxaparin is being used for deep vein thrombosis prophylaxis (measures taken to prevent DVT).
For those who travel, it is recommended that they get up and walk every couple of hours during a long trip.
Compression stockings may be helpful in preventing future deep vein thrombosis formation in patients with a previous history of a clot

read more

Hemophilia

A rare inherited bleeding disorder in which the blood does not clot normally. Persons with hemophilia may bleed for a longer time than others after an injury or accident. They also may bleed internally, especially in the joints (knees, ankles, and elbows).
Babies born with hemophilia are missing or have a low level of a protein needed for normal blood clotting or blood coagulation. The protein is called a clotting factor.
About 18,000 people in the United States have hemophilia. Each year, about 400 babies are born with the disorder. Hemophilia usually occurs only in males (with very rare exceptions).
A person with hemophilia has a problem with certain proteins in the blood called clotting factors. Hemophilia can be due to:

• A low level of one of the clotting factors
• A clotting factor that is completely missing

When clotting factors are missing, or your body does not have enough of these factors, it can take a long time for your blood to clot after an injury or accident.

What is clotting?

An injury (like a cut) to a blood vessel causes a complex chain of events that results in a blood clot. This clotting process is also called blood coagulation. Clotting is your body's reaction to bleeding and keeps you from losing too much blood. Losing too much blood can be life threatening and can damage your internal organs.

What is a clotting factor?

Clotting factors are proteins in the blood that work with platelets – a type of small blood cell – to help the blood to clot. When blood vessels are damaged, clotting factors help the platelets stick together to plug cuts and breaks at the site of the injury.
In people with hemophilia, blood does not clot as it should because it is missing or has low levels of one of these clotting factors. If blood doesn't clot as quickly or as well as it should, then:

• Heavy blood loss can occur.
• Body organs and tissues can be injured.
• These conditions can result in permanent damage or death.

Sometimes people with hemophilia need infusions of a clotting factor or factors to stop bleeding.

Types of hemophilia

The two main types of hemophilia are:

• Hemophilia A: Clotting factor VIII (8) is low or missing. About 9 of 10 people with hemophilia have type A.
• Hemophilia B: Clotting factor IX (9) is low or missing.

Hemophilia also can be acquired when antibodies to these clotting factors form and block their function. Only inherited hemophilia is discussed here.
Hemophilia can be:

• Mild
• Moderate
• Severe

Mild, moderate, or severe hemophilia is determined by the amount of clotting factor in the blood. About 7 of 10 people with hemophilia A have the severe form. Normal persons have a factor VIII activity of 100 percent; persons with severe hemophilia A have a factor VIII activity of less than 1 percent.

What causes hemophilia?

Hemophilia is an inherited disorder. It is caused by a defect in the genes that determine how the body makes blood clotting factors VIII and IX. These genes are located on the X chromosomes, which determine whether a baby is a boy or girl.
Chromosomes come in pairs. Females have two X chromosomes, while males have one X and one Y chromosome. A woman is a "carrier" if she has a defective gene for factor VIII or factor IX on one of her X chromosomes. She can pass the defective gene on to her children.

• If she has a son, there is a one in two (50 percent) chance that he will have hemophilia.
• If she has a daughter, there is a one in two (50 percent) chance that the daughter will be a carrier.

A man who has hemophilia cannot pass the disorder on to his sons. All of his daughters, however, will be carriers.

Very rarely, a girl is born with hemophilia. This can happen if her father has hemophilia and her mother is a carrier.
Some males with the disorder are born to mothers who are not carriers. In these cases, a random change (mutation) occurs in the gene as it is passed to the child.

Signs and symptoms of hemophilia

The major signs and symptoms of hemophilia are bleeding and bruising. Internal bleeding is common in people with severe hemophilia. If not treated promptly, internal bleeding can lead to damaged joints, muscles, or other parts of the body.
The extent of bleeding depends on the type and severity of the condition:

• Children with very mild hemophilia may not have noticeable symptoms for years. Often, the first sign is heavy bleeding from a dental procedure, an accident, or surgery.
• Children with mild to moderate hemophilia may not have any signs or symptoms at birth.
• Males with severe hemophilia may bleed heavily after circumcision.

In most children, the first signs are:

• Heavy bruising and bleeding from the gums as they cut their baby teeth
• Bumps and bruises from frequent falls as they learn to walk
• Swelling and bruising from bleeding in the joints, soft tissue, and muscles

Females who are carriers usually have enough clotting factors from their one normal gene to prevent serious bleeding problems.
The most common signs or symptoms in older children and adults are:

• Bleeding in the joints (hemarthrosis)
• Bleeding and bruising in the soft tissue and muscles
• Bleeding in the mouth from a cut or bite or loss of a tooth
• Nosebleeds for no obvious reason
• Blood in the urine (from bleeding in the kidneys or bladder)
• Blood in the stool (from bleeding in the intestines or stomach)

Bleeding in the joints is the most common problem in persons with severe hemophilia. Bleeding often occurs without an injury. It can go on for days if not treated. However, people with hemophilia can learn to recognize early symptoms of bleeding in the joints and get treatment quickly. Early treatment can help limit damage to the joints.
Although bleeding can occur in any joint, the most common places are the:

• Knees
• Elbows
• Ankles

The signs and symptoms of bleeding in the joints are:

• Tightness in the joint with no real pain is usually the first sign.
• Tightness and pain may occur before any visible signs of bleeding.
• The joint becomes swollen and hot to touch as time passes. Bending or extending the joint is painful.
• Swelling continues as bleeding continues, and all movement in the joint is lost. Pain can be severe.

The bleeding slows after several days when the joint is full of blood.

If not treated, the bleeding can lead to disabling arthritis in the joints.
Bleeding in the brain, a very serious complication of hemophilia, requires emergency treatment. This bleeding can happen after a simple bump on the head or a more serious injury. The signs and symptoms are:

• Long-lasting painful headaches
• Vomiting many times
• Changes in behavior or being very sleepy
• Sudden weakness or clumsiness of the arm or leg
• Neck pain or stiffness
• Double vision
• Difficulty walking
• Convulsions or seizures

Diagnosis

If hemophilia is suspected or if you appear to have a bleeding problem, your doctor will take a personal and family history, do a physical exam, and order blood tests.
Blood tests are used to determine:

• How long it takes for your blood to clot
• Whether your blood has low levels of any of the clotting factors
• Whether one of the factors is completely missing from your blood

The test results will show if you have hemophilia, what type of hemophilia you have, and how severe it is.
Hemophilia A and B are classified as mild, moderate, or severe, depending on the amount of clotting factor VIII (8) or IX (9) in the blood.
Mild hemophilia: >5–30 percent of normal factor
Moderate hemophilia: 1–5 percent of normal factor
Severe hemophilia: Less than 1 percent of normal factor
Severe hemophilia can cause serious bleeding problems in babies. Therefore, children with severe hemophilia are usually diagnosed during the first year of life. People with milder forms of hemophilia may not be diagnosed until they are adults.
The bleeding problems of hemophilia A and hemophilia B are the same. These two types of hemophilia can only be distinguished by special blood tests. Distinguishing hemophilia A from hemophilia B is important because the treatments are different.

Treatment

The main treatment for hemophilia is replacement therapy – giving or replacing the clotting factor that is too low or missing. Concentrates of the clotting factor are infused, or injected, directly into the bloodstream. The specific factors used to treat hemophilia are:

• Factor VIII for hemophilia A
• Factor IX for hemophilia B

Replacement therapy can be used:

• To prevent bleeding (prophylactic or preventive therapy)
• To stop bleeding when it occurs, on an as-needed basis (demand therapy)

The type of treatment you receive depends on several things, including whether you have mild, moderate, or severe hemophilia.

• Mild hemophilia. Replacement therapy is usually not needed for mild hemophilia; however, a medicine called desmopressin (DDAVP) is sometimes given to raise the body's levels of factor VIII. Since the effect wears off with chronic use, it is applied only in certain situations (for example, prior to dental work or participation in sports) to prevent or reduce bleeding. Desmopressin does not help in hemophilia B.

• Moderate hemophilia. You may need treatment only when bleeding occurs. You will need to learn to recognize signs and symptoms of bleeding so that you can get treatment as quickly as possible. You may also have treatment to prevent bleeding that could occur when participating in some activity.

• Severe hemophilia. You usually need long-term or shorter term preventive therapy to prevent bleeding that could cause permanent damage to your joints, muscles, or other parts of the body. Some people with severe hemophilia receive treatment only when bleeding occurs, however. When bleeding occurs, it is important to get treatment as soon as possible. Delayed treatment can lead to complications. Learn to recognize signs of bleeding, and make sure that it is treated quickly.

Sources of clotting factors

The clotting factor concentrates used in replacement therapy come from two sources:

• Blood from human donors
• Lab-produced clotting factors, called recombinant factors, that are not made from human blood

Clotting factor concentrate infusions need to be given once daily or more frequently when treatment is started, because half of the activity of factor VIII is gone in 8–12 hours and half of the activity of factor IX is gone in 12–24 hours.
Clotting factors used in replacement therapy today are:

• Very powerful – only a small amount is needed to control bleeding.
• Easy to store, mix, and use at home – it takes only about 15 minutes to receive the factor.

Replacement therapy to prevent bleeding

Replacement therapy can be given on a regular basis to prevent bleeding. The goal is to keep the levels of clotting factors in the blood high enough that bleeding will not occur.
This therapy is more likely to be used in persons with severe hemophilia. It is often used in children to prevent damage to joints from bleeding.
Preventive replacement therapy can be given:

• On a long-term basis, usually given two or three times a week
• On a shorter term basis, such as over a few months
• On a short-term basis before participating in an activity that could cause bleeding

This therapy can be intensive and expensive. Preventive therapy is often given at home.

Replacement therapy to stop bleeding when it occurs

Replacement therapy can be given as needed, or on demand, to stop bleeding as soon as possible after it begins. The goal is to prevent damage to joints, muscles, or other parts of the body from bleeding. This therapy is common for people with mild or moderate hemophilia.
The amount of clotting factor given depends on:

• The type of hemophilia
• The bleeding site and severity of the bleeding
• The person's weight
• Whether the person has developed an antibody that neutralizes or knocks out the activity of the clotting factor

Therapy that is given as needed is less intensive and less expensive than regular preventive therapy. However, there is a risk that bleeding will cause damage before the treatment is given.
People who use this form of treatment must learn to recognize bleeding when it occurs. Treatment must begin right away to limit damage. Family members should also learn to watch for signs of bleeding in a child. Children sometimes ignore signs of bleeding because they want to avoid the discomfort of treatment.

Complications of replacement therapy

Complications of treatment include:

• Developing antibodies, which are proteins that knock out the activity of clotting factors
• Damage to joints, muscles, or other parts of the body, resulting from delays in treatment

Antibodies to the clotting factor

Antibodies destroy the clotting factor before it has a chance to work. This is a very serious problem, because the main treatment for hemophilia – replacing clotting factors – is no longer effective.
Antibodies to clotting factor develop in about:

• Twenty percent of people with severe hemophilia A
• One percent of people with hemophilia B

When antibodies develop, doctors may use larger doses of clotting factors or try different sources of the clotting factor. Sometimes, antibodies go away. Researchers are studying ways to deal with antibodies to clotting factors.

Viruses from human blood factors

The viruses that cause AIDS (HIV) and hepatitis can be carried in clotting factors. However, no documented case of transmission of these viruses has occurred for about a decade. Transmission of viruses has been prevented by:

• Careful screening of donors
• Testing of donated blood products
• Treating donated blood products, used to create clotting factors, with a detergent and heat to destroy viruses

Researchers continue to find ways to make blood products safer.

Damage due to delays in treatment

When treatment for bleeding is delayed, damage to the area affected (such as a joint) can occur. It is important for persons with hemophilia to learn to recognize signs of bleeding as soon as possible after bleeding starts and to get treatment quickly.
Home treatment
Both preventive and as-needed therapy can be done at home. Many people learn to do the infusions at home for their child or for themselves. Home treatment has several advantages:

• You or your child can get treatment quicker when bleeding happens. Early treatment means that fewer complications are likely to occur.
• Fewer visits to the doctor or emergency room are needed.
• Home infusions cost less than treatment in a medical care setting.
• Home treatment helps children accept treatment and take responsibility for their own health.

Discuss options for home treatment with your doctor or your child's doctor. A doctor or other health care provider can teach you the steps and safety procedures for home treatment. Another valuable resource for learning about home treatment is through hemophilia treatment centers (HTCs) (see below).
Vein access devices can be surgically implanted to make it easier to access a vein to do the infusions. These devices can be helpful when infusions are done on a frequent basis. However, infections can be a problem with these devices. Your doctor can help you decide if this type of device is right for you or your child.

Hemophilia treatment centers

A nationwide network of HTCs, funded by the Federal Government, is an important resource for families and individuals affected by hemophilia. The medical experts in these centers provide treatment, education, and support. They can teach you or your child how to do home infusions safely. Center staff can also provide information to your doctor.
People who get care in these centers are less likely than those who get care elsewhere to have bleeding complications. This lack of complications may be due to the centers' emphasis on prevention of bleeding and the education and support provided to patients and their caregivers.

Other treatments

• Desmopressin (DDAVP) is a synthetic hormone used to treat people with mild to moderate hemophilia A. DDAVP cannot be used to treat hemophilia B or severe hemophilia A. DDAVP stimulates the release of factor VIII and von Willebrand factor stored in blood vessels and increases the level of these proteins in the blood. Von Willebrand factor carries and binds factor VIII, which then can stay in the blood circulation longer. DDAVP usually is given by injection or in a nasal spray.
• Antifibrinolytic drugs (including tranexamic acid and aminocaproic acid) are medicines used with factor treatment. They are usually given as a pill to help keep clots from breaking down. They are most often used:
  • Before dental work
  • For treating bleeding from the mouth or nose
  • For mild intestinal bleeding

read more

Raynaud's phenomenon

   Raynaud's phenomenon (RP) is a condition resulting in a particular series of discolorations of the fingers and/or the toes after exposure to changes in temperature (cold or hot) or emotional events. Skin discoloration occurs because an abnormal spasm of the blood vessels causes a diminished blood supply to the local tissues. Initially, the digit(s) involved turn white because of the diminished blood supply. The digit(s) then turn blue because of prolonged lack of oxygen. Finally, the blood vessels reopen, causing a local "flushing" phenomenon, which turns the digit(s) red. This three-phase color sequence (white to blue to red), most often upon exposure to cold temperature, is characteristic of RP.

Raynaud's phenomenon most frequently affects women, especially in the second, third, or fourth decades of life. People can have Raynaud's phenomenon alone or as a part of other rheumatic diseases. When it occurs alone, it is referred to as "Raynaud's disease" or primary Raynaud's phenomenon. When it accompanies other diseases, it is called secondary Raynaud's phenomenon.

What causes Raynaud's phenomenon?

The causes of primary and secondary RP are unknown. Both abnormal nerve control of the blood-vessel diameter and nerve sensitivity to cold exposure have been suspected as being contributing factors. The characteristic color changes of the digits are in part related to initial blood-vessel narrowing due to spasm of the tiny muscles in the wall of the vessels, followed by sudden opening (dilation), as described above. The small arteries of the digits can have microscopic thickness of their inner lining, which also leads to abnormal narrowing of the blood vessels.

Conditions  associated with Raynaud's phenomenon

Raynaud's phenomenon has been seen with a number of conditions, including rheumatic diseases (scleroderma, rheumatoid arthritis, systemic lupus erythematosus), hormone imbalance (hypothyroidism and carcinoid), trauma (frostbite, vibrating tools), medications (propranolol [Inderal], estrogens without additional progesterone, nicotine, bleomycin [Bleoxane] used in cancer treatment, and ergotamine used for headaches), and even rarely with cancers.

symptoms and signs

Symptoms of RP depend on the severity, frequency, and duration of the blood vessel spasm. Most patients with mild disease only notice skin discoloration upon cold exposure. They may also experience mild tingling and numbness of the involved digit(s) that will disappear once the color returns to normal. When the blood-vessel spasms become more sustained, the sensory nerves become irritated by the lack of oxygen and can cause pain in the involved digit(s). Rarely, poor oxygen supply to the tissue can cause the tips of the digits to ulcerate. Ulcerated digits can become infected. With continued lack of oxygen, gangrene of the digits can occur.

Less common areas of the body that can be affected by RP include the nose, ears, and tongue. While these areas rarely develop ulcers, they can be associated with a sensation of numbness and pain.

Patients with secondary RP can also have symptoms related to their underlying diseases. RP is the initial symptom of 70% of patients with scleroderma, a skin and joint disease. Other rheumatic diseases frequently associated with RP include systemic lupus erythematosus, rheumatoid arthritis, and Sjogren's syndrome.

Diagnosis

In patients with the characteristic sequence of skin-color changes of the digits upon cold exposure, diagnosing RP is not difficult. Sometimes, certain patterns in the tiny blood vessels (capillaries) adjacent to the fingernails of patients with RP can be seen using a magnifying viewing instrument. Abnormal nail-fold capillary patterns can suggest the possibility of an associated rheumatic condition. There is, however, no single blood test to help the doctor to confirm the diagnosis. The doctor can order certain blood tests (for example, sedimentation rate, rheumatoid factor, antinuclear antibody, thyroid hormone levels, and protein levels) to exclude associated rheumatic diseases and thyroid disorders. The doctor can also perform certain maneuvers with the patient's extremities to exclude pinched blood vessels that can produce symptoms that mimic RP, such as in thoracic outlet syndrome.

Typically patients with Raynaud's phenomenon that is a manifestation of a rheumatic disease have elevated blood sedimentation rates and antinuclear antibodies. Furthermore, capillary nail fold abnormalities can frequently be found as described above.

Treatment

Management of Raynaud's phenomenon involves protecting the fingers and the toes from cold, trauma, and infection. Medications that can aggravate blood vessel spasm should be avoided by patients with RP. In patients with persistent symptoms, medications that dilate the blood vessels can be administered.

Patients with Raynaud's phenomenon who have no symptoms other than the color changes of extremities may require only measures to prevent complications. Prevention measures are important in primary and secondary RP regardless of the severity. Simple initial care involves keeping the body warm, especially the extremities. Warm clothing in colder environments is essential. Cotton gloves can be helpful while searching the freezer. Room temperatures should not be too cool. Rubber gloves protect the hands and prevent cooling while washing dishes. Barefoot walking should be minimized. Compression of the blood vessels by tight-fitting wrist bands, rings, or footwear should be avoided.

Those with RP should guard their hands and feet from direct trauma and wounds. Any wounds or infections should be treated early to prevent more serious infections. Avoiding emotional stresses and tools that vibrate the hand may reduce the frequency of attacks. Biofeedback can also help to decrease the severity and frequency of RP in some patients.

Direct and indirect (passive) smoking should be avoided by patients with RP. The chemicals in tobacco smoke can cause blood-vessel constriction and lead to atherosclerosis (hardening of the arteries), which can further impair oxygen supply to the extremities.

Care of the nails must be done carefully to avoid injuring sensitive toes and fingertips. Ulcers on the tips of the digits should be monitored closely by the doctor. These can become infected. Gently applied finger splints are used to protect ulcerated areas. Ointments that open the blood vessels (nitroglycerin ointment) are sometimes used on the sides of severely affected digits to allow increased blood supply and healing.

Medications that can aggravate symptoms of RP by leading to increased blood-vessel spasm include over-the-counter cold and weight-control preparations, such as pseudoephedrine (Actifed, Chlor-Trimeton, Cotylenol, and Sudafed). Beta blockers, medicines used for high blood pressure and heart disease, can also worsen RP. These include atenolol (Tenormin), metoprolol (Lopressor), nadolol (Corgard), and propranolol.

Patients with persistent or bothersome symptoms may be helped by taking oral medications that open (dilate) blood vessels. These include calcium antagonists, such as diltiazem (Cardizem, Dilacor), nicardipine (Cardene), nifedipine (Procardia), and other medicines used in blood pressure treatment, such as methyldopa (Aldomet) and prazocin (Minipress). Recent research has shown that the blood-pressure drug losartan (Cozaar, Hyzaar) can reduce the severity of episodes of RP possibly more than nifedipine.

Medications that "thin" the blood, such as low doses of aspirin or dipyridamole (Persantine), are sometimes helpful.

Some patients with persistent symptoms can benefit by adding a medication called pentoxifylline (Trental) which makes the red blood cells more pliable, thereby improving circulation.

Severe RP can lead to gangrene and the loss of digits. In rare cases of severe disease, nerve surgery called "sympathectomy" is sometimes considered. In this procedure, to prevent blood-vessel spasm, the nerves that stimulate the constriction of the vessels (sympathetic nerves) are surgically interrupted. Usually, this is performed during an operation that is localized to the sides of the base of the fingers at the hand. Through small incisions the tiny nerves around the blood vessels are stripped away. This procedure is referred to as a digital sympathectomy.

Research

Researchers have reported finding a substantial genetic (inherited) contribution both to the symptoms of RP and to the associated blood-vessel changes of patients with Raynaud's phenomenon.

Other researchers are studying nitric oxide and its potential relationship to Raynaud's phenomenon. A gel is being studied which might promote local production of nitric oxide in involved digits. The local nitric oxide, it seems, may open the blood vessels and improve the impaired circulation.

Key points

• Raynaud's phenomenon is characterized by a pale-blue-red sequence of color changes of the digits, most commonly after exposure to cold.
• Raynaud's phenomenon occurs because of spasm of blood vessels.
• The cause of Raynaud's phenomenon is unknown, although abnormal nerve control of blood-vessel diameter and nerve sensitivity to cold are suspected of being involved.
• Symptoms of Raynaud's phenomenon depend on the severity, frequency, and duration of the blood-vessel spasm.
• There is no blood test for diagnosing Raynaud's phenomenon.
• Treatment of Raynaud's phenomenon involves protection of the digits, medications, and avoiding emotional stresses, smoking, cold temperature, and tools that vibrate the hands.

read more

Thromboangiitis obliterans

Thromboangiitis obliterans is a rare disease in which blood vessels of the hands and feet become obstructed.

Causes

Thromboangiitis obliterans (Buerger's disease) is caused by vasculitis (inflammation of the blood vessels).

The blood vessels of the hands and feet are especially affected, becoming constricted or totally blocked. This reduces blood flow to the hand and foot tissues, resulting in pain and eventually damage.

Thromboangiitis obliterans affects about 6 of every 10,000 people. It almost always affects men ages 20 to 40 who have a history of smoking or chewing tobacco.

The condition may also be associated with a history of Raynaud's disease.

This disorder is very uncommon in children, but may occur in those with autoimmune diseases.

Symptoms

• Hands or feet may be pale, red, or bluish
• Hands or feet may feel cold
• Pain in the hands and feet
  • Acute, severe
  • Burning or tingling
  • Often occurring at rest
• Pain in the legs, ankles, or feet when walking (intermittent claudication)
  • Often located in the arch of the foot
• Skin changes or ulcers on hands or feet

Note: Symptoms may worsen with exposure to cold or with emotional stress. Usually, two or more limbs are affected.

Exams and Tests

The hands or feet may show enlarged, red, tender blood vessels. The pulse in the affected hands or feet may be low or absent.

The following tests may show blockage of blood vessels in the affected hands or feet:

• An angiography/arteriography of the extremity
• A Doppler ultrasound of the extremity

Blood tests for other causes of vasculitis and inflammation may be done. Rarely, in cases where the diagnosis is unclear, a biopsy of the blood vessel is done.

Treatment

There is no cure for thromboangiitis obliterans. The goal of treatment is to control symptoms.

To prevent amputation, the patient must stop using tobacco and should avoid cold temperatures and other conditions that reduce circulation to the hands and feet.

Applying warmth and exercising gently may help increase circulation.

Cutting the nerves to the area (surgical sympathectomy) may help control pain. Aspirin and vasodilators may also used. Amputation of the extremity may be necessary if infection or extensive tissue death occurs.

Outlook (Prognosis)

Symptoms of thromboangiitis obliterans may disappear if the person stops tobacco use. For some, amputation is unavoidable.

Possible Complications

• Amputation
• Gangrene (tissue death)
• Loss of circulation beyond the affected extremity

When to Contact a Medical Professional

Call your health care provider if you have symptoms of thromboangiitis obliterans, if you have thromboangiitis obliterans and symptoms get worse despite treatment, or if new symptoms develop.

Prevention

Those with a history of Raynaud's disease or thromboangiitis obliterans should avoid all tobacco use.

Alternative Names

Buerger's disease

read more

Varicose Veins

Varicose veins are distended branches of the major veins in the leg. They become distended due to failure of the valve s in the main veins which allows blood to fall back down the leg (reflux).  Venous reflux is the major cause of most venous diseases and is almost always the cause of varicose veins.

Varicose veins develop in the superficial veins of the leg and mainly affect the great saphenous vein although it is not uncommon for the small saphenous vein to be involved.
As the vein dilates the wall stretches in both width and length so that the vein becomes tortuous.
As the situation gets worse the veins become so dilated that large sacs form at the bends and the vein takes on a snake–like twisted effect.
Areas of stagnation occur where the bends are so extreme that blood does not  flow around them fully.
Rather than a fast flowing ‘river’, the vein will sometimes thrombose, leading to inflammation of the vein called superficial thhrombophlebitis.
Venous ulcers will continue to recur unless the underlying varicose veins are treated. Some people suffer only cosmetically, but very often people will complain of aching legs, particularly at the end of the day.

Causes

The specific causes of vein problems are undetermined and will vary according to the individual.  Contributary factors may include –

• Hereditary: there is a known relationship between hereditary factors and the development of varicose veins in the general population
  
• Age: the development of varicose veins may occur at any age but will usually start between the ages of 18 and 35, with peaks between 50 and 60.
  
• Gender: females are assumed to be affected more than males but this is more likely to be due to the fact that  females seek medical treatment more readily than men. In fact research has shown that the incidence of varicose veins occurring in both men and women is similar.
  
• Pregnancy: circulating hormones can weaken the vein walls. An enlarged uterus can compress veins causing higher vein pressure and dilated veins. Varicose veins that form during pregnancy can spontaneously improve and often disappear within a few months of childbirth. Research has shown that women who have developed valve problems (which are directly related to varicose veins) prior to pregnancy go on to develop varicose veins during or after the pregnancy. So pregnancy in itself does not cause varicose veins in the majority of people and varicose veins would have developed in any event at some point in the future.
  The above is true for about 98% of pregnant women with associated varicose veins. The remaining 2% of women do get varicose veins because of pregnancy. These women suffer from  ‘ovarian’ or ‘pelvic’ vein reflux which can typically cause vulval varicose veins or varicose veins of the upper inner thigh.
  
• Lifestyle: standing and sitting for long periods; tight clothing; obesity; heat; sedentary lifestyle; excessive alcohol intake and smoking, high heeled shoes; ‘the pill’ and, number of pregnancies are all associated but not a cause of varicose veins.

Preve ntion Tips

• Exercise regularly: it is often recommended that 3–4 times a week of approximately 20 minutes of fairly strenuous exercise, such as walking or swimming, reduces pressure in the veins generally. It is of course good for overall health.Exercise improves your leg strength, circulation and vein strength.
• Move legs frequently: flexing ankles periodically will pump the blood out of the legs. When standing or sitting for long periods, flex the ankles 10 times and repeat every ten minutes and try taking a short stroll every 30 minutes.
• Support/compression stockings: these provide extra pressure from the outside to assist with venous blood flow back to the heart. They reduce reflux and pressure in the veins and should be considered for long haul air travel and prolonged travel in cramped spaces generally.
• Avoid excessive heat on legs: hot baths or Jacuzzis may lead to increased vein distension and more pooling of blood.
• Elevate the legs: where possible the objective is keep the legs above the level of the heart thus providing a natural gravitational force of blood to the heart. So where possible, when resting elevate your legs as much as possible.
• Healthy diet: Make sure you eat a healthy diet, with enough fibre, to avoid constipation which can contribute to varicose veins.
• Maintaining a healthy weight

Investigations

Proper diagnosis is essential in order to devise an appropriate and successful treatment. Colour Duplex Ultrasound is the most reliable way and is the best current method of identifying  the location and extent of venous problems. This is a minor procedure carried out by a vascular technologist and maps which veins are working correctly and those which are not. Without this, even the most skilled practitioner may treat the wrong vein. Some evidence suggests that about 30% of patients have received the wrong operation as a result, and therefore it is not surprising that varicose veins come back.

A clear gel is put on the skin and the ultrasound probe is then placed onto this. A vascular technologist performs the scan in the clinic and can see the veins and the blood flowing through them. It sometimes also shows the valves in action and the flow rate and patterns of blood also illustrates the condition of the valves.
The rates of success for leg vein treatment, and the vastly reduced risk of recurring vein problems, is a direct result of this testing method.

Venous Ulcers

Venous ulcers account for 90% of the ulcers seen in clinical practice, and it is estimated that 1% of the population will suffer from a venous ulcer at some point in their life. Many people that have venous ulcers

have associated varicose veins.
It is this association that worries most people who have varicose veins and perhaps presents a further motive not to ignore varicose veins in the long term.
An ulcer can occur due to the chronic rise in pressure as a result of too much blood falling back through the veins (reflux). Damage to the delicate venous capillaries that should drain into the larger veins can result in the leaking of blood and plasma into the surrounding tissue.
Chemicals and enzymes in the blood and plasma then cause inflammation, itching, swelling and soreness. Eventually, this can lead to a break down of the skin causing an ulcer.
Ulcers are unlikely to heal unless the underlying cause is treated, in this case, the venous reflux. Hence the importance in dealing with varicose veins earlier rather than later.

Varicose Vein Treatments

Radiofrequency Occlusion

Radiofrequency Occlusion is an alternative to surgical stripping of veins. It treats the vein by heating it, causing the vein to contract and then close. Once the diseased vein is closed, other healthy veins take over and empty blood from the legs. Normal blood flow is re-established quickly and symptoms should improve noticeably.

To perform the procedure, the surgeon uses an ultrasound machine to map the vein, before numbing the area with a local anaesthetic. A needle is then placed into the lower end of the diseased vein, through which a small sheath is inserted. A radiofrequency catheter is placed through the sheath and advanced to the upper end of the diseased vein. Local anaesthesia is then delivered to the entire vein. As the catheter is slowly withdrawn back, the vein is heated.It then collapses and seals shut.

Following the procedure the catheter is removed, a bandage is placed over the incision site and compression stockings are prescribed for a short time. Patients are encouraged to mobilise and long periods of standing and inactivity are to be avoided. This procedure is minimally invasive with little discomfort and most patients can walk out after treatment within an hour.

Possible side effects of this procedure are slight bruising, skin numbness, skin burns, blood clots and phlebitis. However side effects are uncommon and the procedure offers a safer and more effective treatment than traditional surgical methods. Radiofrequency ablation is far less painful than surgical stripping and EVLT treatment. Bruising and recovery times are also greatly reduced.

Following radiofrequency ablation small residual veins may be treated with phlebectomy or ultrasound guided sclerotherapy.

Endovenous Laser Treatment (EVLT )

The EVLT procedure is a minimally invasive laser procedure in treating varicose veins. The laser energy heats the blood in the veins causing them to seal shut so that blood cannot flow through it. This eliminates the bulging of the vein at the source. After the treatment the blood in the faulty veins will be diverted to the many normal veins in the leg.

As with radiofrequency, the surgeon uses an ultrasound machine to map the vein, before numbing the area with a local anaesthetic. A needle is then placed into the lower end of the diseased vein, through which a small sheath is inserted. A laser catheter is placed through the sheath and advanced to the upper end of the diseased vein. Local anaesthesia is then delivered to the entire vein. As the catheter is slowly withdrawn back, the blood in the vein is heated causing the vein to collapse and seal shut.

This type of procedure takes around 45 minutes with a local anaesthetic and is done as an out-patient procedure.

The procedure leaves no visible scarring, and there is some post-operative pain although not as much as surgery. Walking is recommended immediately.

There are always risks from the use of lasers, although as a standard precaution special goggles are worn to protect the eyes in the event of accidentally coming into contact with the laser beam. Side effects may include slight bruising, pain, skin burns, blood clots and phlebitis.

Sclerotherapy for varicose veins under ultrasound guidence

A special chemical called a sclerosant is injected under ultrasound guidence into a varicose vein.This causes damage and inflammation and leads to the closure of the vein. The sclerosant may cause localised feelings of burning or cramping for several minutes but generally the procedure is relatively painless.

After the injection pressure is applied to the veins to prevent blood returning when the patient stands up. A compression stocking is worn for several weeks after the procedure to aid this process.

Treatment will normally take up to 30 minutes but can take less time, depending on how many veins there are to be treated. The number of injections and treatment sessions required depends on the extent of the varicose vein condition.

Foam sclerosant is also used in many cases, which offers advantages over liquid sclerosant. Foam makes better contact with the inside of the vein wall and stays in the vein longer thus generating more effect from the active chemical.

Side effects albeit rare, in sclerotherapy include skin colour changes around the treated area which usually disappear after 6-12 months, but in rare cases may be permanent. Occasionally there may be itching, bruising, pain, and blistering around the treated area.Very rarely a patient may experience localised scarring or ulceration and blood clots or damage in the deep vein system. Matting may occur in the treated area. This is when a leash of smaller vessels appear in the treated area but often resolves.

Phlebectomy

Phlebectomy is a method of removing varicose veins on the surface of the legs. It is done under local anaesthetic. This procedure involves making tiny incisions through which the varicose veins are removed. The incisions are so small that stitches are not required. Veins can collapse considerably and are very flexible and even large veins can be removed through a very small incision. Patients can also usually walk immediately after the procedure. Compression bandages and stockings are worn for a period after treatment. Walking or cycling is very often recommended to reduce the risk of blood clotting, reduce pressure in the vein, and increase the flow of blood.

Side effects may include light bruising, discomfort and nerve damage but these are rarely permanent.

Open vein surgery-vein stripping

During this procedure problem veins are tied up and removed from the leg. This treatment requires general anaesthetic. An incision is made in the groin along with many more incisions lower down the leg. A hospital stay may be required and pain killers, support bandages and leg elevation is needed post surgery.

Side effects may include known problems associated with general anaesthesia, wound infection, permanent scarring, nerve tissue damage, deep vein thrombosis and significant leg pain.

Origin Medical does not use this traditional technique unless for specific medical reasons (extremely rare) a patient cannot benefit from endovenous procedures such as radiofrequency or endovenous laser.

Compression stockings

Compression stockings are a simple and inexpensive way to treat varicose veins. They are designed to reduce the blood pooling due to venous reflux. The stockings apply pressure, with the highest pressure starting at the bottom around the ankles and a gradual reduction in pressure as they go up the leg. This encourages blood not to back flow, and to maintain its natural direction back towards the heart. They can be procured in varying strength levels depending on the individual’s condition.

Although they do not eliminate varicose veins, they do help to alleviate symptoms caused by varicose veins, such as aching, heaviness, and swelling, as well as help to prevent worsening. Compression stockings can also be used to reduce the risk of blood clots in airplanes and long distance travelling generally.

Compression stockings are worn after vein treatments to keep pressure on the treated area. This prevents blood returning in to the treated area reducing side effects and improving long term results.

Why do varicose veins recur after treatment?

There are three main reasons why varicose veins recur (After treatment)

1. If treatment is performed without ultrasound then there is an element of imprecision in the location and diagnosis of incompetent veins, thus increasing considerably the risk of missing the problem or under treating it.
2. If the old ‘tie and strip’ type operation is done, a new vein may grow as the body recanulates the site where the old vein was. (Revascularisation 23% after one year but less than 1% if using endovenous laser). The radiofrequency technique also avoids this.
3. New varicose veins can form: veins that were normal on the day of treatment but which can develop problems later on. This occurs in about 2% of people.

read more

Low Blood Pressure (Hypotension)

Blood pressure is the force exerted by circulating blood on the walls of blood vessels, and constitutes one of the principal vital signs of life, which also include heart beat, rate of breathing, and temperature. Blood pressure is generated by the heart pumping blood into the arteries and is regulated by the response by the arteries to the flow of blood.

An individual's blood pressure is expressed as systolic/diastolic blood pressure, for example, 120/80.The systolic blood pressure (the top number) represents the pressure in the arteries as the muscle of the heart contracts and pumps blood into them. The diastolic blood pressure (the bottom number) represents the pressure in the arteries as the muscle of the heart relaxes after it contracts. Blood pressure always is higher when the heart is pumping (squeezing) than when it is relaxing.

Systolic blood pressure for most healthy adults falls between 90 and 120 millimeters of mercury (mm Hg). Normal diastolic blood pressure falls between 60 and 80 mm Hg. Current guidelines define normal blood pressure as lower than 120/80. Blood pressures over 130/80 are considered high. High blood pressure increases the risk of developing:

• heart disease,
• kidney disease,
• hardening of the arteries (atherosclerosis or arteriosclerosis),
• eye damage, and
• stroke.

Low blood pressure (hypotension) is pressure so low it causes symptoms or signs due to the low flow of blood through the arteries and veins. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidney, the organs do not function normally and may be permanently damaged.

Unlike high blood pressure, low blood pressure is defined primarily by signs and symptoms of low blood flow and not by a specific blood pressure number. Some individuals may have a blood pressure of 90/50 with no symptoms of low blood pressure and therefore do not have low blood pressure. However, others who normally have high blood pressure may develop symptoms of low blood pressure if their blood pressure drops to 100/60.

Is low blood pressure bad for your health?

People who have lower blood pressures have a lower risk of stroke, kidney disease, and heart disease. Athletes, people who exercise regularly, people who maintain ideal body weight, and non-smokers tend to have lower blood pressures. Therefore, low blood pressure is desirable as long as it is not low enough to cause symptoms and damage organs in the body.

What are low blood pressure signs and symptoms?

When the blood pressure is not sufficient to deliver enough blood to the organs of the body, the organs do not work properly and may be permanently damaged. For example, if insufficient blood flows to the brain, brain cells do not receive enough oxygen and nutrients, and a person can feel lightheaded, dizzy, or even faint.

Going from a sitting or lying position to a standing position often brings out symptoms of low blood pressure. This occurs because standing causes blood to "settle" in the veins of the lower body, and this can lower the blood pressure. If the blood pressure is already low, standing can make the low pressure worse, to the point of causing symptoms. The development of lightheadedness, dizziness, or fainting upon standing caused by low blood pressure is called orthostatic hypotension. Normal individuals are able to compensate rapidly for the low pressure created by standing with the responses discussed previously and do not develop orthostatic hypotension.

When there is insufficient blood pressure to deliver blood to the coronary arteries (the arteries that supply blood to the heart's muscle), a person can develop chest pain (a symptom of angina) or even a heart attack.

When insufficient blood is delivered to the kidneys, the kidneys fail to eliminate wastes from the body, for example, urea and creatinine, and an increase in their levels in the blood occur (for example, elevations of blood urea nitrogen or BUN and serum creatinine, respectively).

Shock is a life-threatening condition where persistently low blood pressure causes organs such as kidney(s), liver, heart, lung, and brain to fail rapidly.

What are the causes of low blood pressure?

Conditions that reduce the volume of blood, reduce cardiac output (the amount of blood pumped by the heart), and medications are frequent causes of low blood pressure.

• Dehydration is common among patients with prolonged nausea, vomiting, and diarrhea. Large amounts of water are lost when vomiting and with diarrhea, especially if the patient does not drink adequate amounts of fluid to replace the depleted water.

Other causes of dehydration include exercise, sweating, fever, and heat exhaustion, or heat stroke. Individuals with mild dehydration may experience only thirst and dry mouth. Moderate to severe dehydration may cause orthostatic hypotension (manifested by lightheadedness, dizziness, or fainting upon standing). Protracted and severe dehydration can lead to shock, kidney failure, confusion, acidosis (too much acid in the blood), coma, and even death.

• Moderate or severe bleeding can quickly deplete an individual's body of blood, leading to low blood pressure or orthostatic hypotension. Bleeding can result from trauma, surgical complications, or from gastrointestinal abnormalities such as ulcers, tumors, or diverticulosis. Occasionally, the bleeding may be so severe and rapid (for example, bleeding from a ruptured aortic aneurysm) that it causes shock and death rapidly.

• Severe inflammation of organs inside the body such as acute pancreatitis can cause low blood pressure. In acute pancreatitis, fluid leaves the blood vessels to enter the inflamed tissues around the pancreas as well as the abdominal cavity, depleting the volume of blood.

Causes of low blood pressure due to heart disease

• Weakened heart muscle can cause the heart to fail and reduce the amount of blood it pumps. One common cause of weakened heart muscle is the death of a large portion of the heart's muscle due to a single, large heart attack or repeated smaller heart attacks. Other examples of conditions that can weaken the heart include medications that are toxic to the heart, infections of the muscle of the heart by viruses (myocarditis), and diseases of the heart's valves such as aortic stenosis.

• Pericarditis is an inflammation of the pericardium (the sac surrounding the heart). Pericarditis can cause fluid to accumulate within the pericardium and compress the heart, restricting the ability of the heart to fill and pump blood.

• Pulmonary embolism is a condition in which a blood clot in a vein (deep vein thrombosis) breaks off and travels to the heart and eventually the lung. A large blood clot can block the flow of blood into the left ventricle from the lungs and severely diminish the blood returning to the heart for pumping. Pulmonary embolism is a life-threatening emergency.

• A slow heart rate (bradycardia) can decrease the amount of blood pumped by the heart. The resting heart rate for a healthy adult is between 60 and 100 beats/minute. Bradycardia (resting heart rates slower than 60 beats/minute) does not always cause low blood pressure. In fact, some highly trained athletes can have resting heart rates in the 40s and 50s (beats per minute) without any symptoms. (The slow heart rates are offset by more forceful contractions of the heart that pump more blood than in non-athletes.) But in many patients bradycardia can lead to low blood pressure, lightheadedness, dizziness, and even fainting.

Several common reasons for bradycardia include: 1) sick sinus syndrome, 2) heart block, and 3) drug toxicity. Many of these conditions occur in the elderly.

1. Sick sinus syndrome: Sick sinus syndrome occurs when the diseased electrical system of the heart cannot generate signals fast enough to maintain a normal heart rate.

1. Heart block: Heart block occurs when the specialized tissues that transmit electrical current in the heart are damaged by heart attacks, degeneration from atherosclerosis, and medications. Heart block prevents some or all of the electrical signals from reaching the rest of the heart, and this prevents the heart from contracting as rapidly as it otherwise would.

1. Drug toxicity: Drugs such as digoxin (Lanoxin) or beta blockers for high blood pressure, can slow the transmission of electricity in the heart chemically and can cause bradycardia and hypotension (see section below "Medications that cause low blood pressure").

• An abnormally fast heart rate (tachycardia) also can cause low blood pressure. The most common example of tachycardia causing low blood pressure is atrial fibrillation. Atrial fibrillation is a disorder of the heart characterized by rapid and irregular electrical discharges from the muscle of the heart causing the ventricles to contract irregularly and (usually) rapidly. The rapidly contracting ventricles do not have enough time to fill maximally with blood before the each contraction, and the amount of blood that is pumped decreases in spite of the faster heart rate. Other abnormally rapid heart rhythms such as ventricular tachycardia also can produce low blood pressure, sometimes even life-threatening shock.

Medications that cause low blood pressure

• Medications such as calcium channel blockers, beta blockers, and digoxin (Lanoxin) can slow the rate at which the heart contracts. Some elderly people are extremely sensitive to these medications since they are more likely to have diseased hearts and electrical conduction tissues. In some individuals, the heart rate can become dangerously slow even with small doses of these medications.

• Medications used in treating high blood pressure (such as ACE inhibitors, angiotensin receptor blockers, beta blockers, calcium channel blockers, and alpha-blockers) can excessively lower blood pressure and result in symptomatic low blood pressure especially among the elderly.

• Water pills (diuretics) such as furosemide (Lasix) can decrease blood volume by causing excessive urination.

• Medications used for treating depression, such as amitriptyline (Elavil), Parkinson's disease, such as levodopa-carbidopa (Sinemet), erectile dysfunction (impotence), such as sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) when used in combination with nitroglycerine, can cause low blood pressure.

• Alcohol and narcotics also can cause low blood pressure.

Other conditions that cause low blood pressure

• Vasovagal reaction is a common condition in which a healthy person temporarily develops low blood pressure, slow heart rate, and sometimes fainting. A vasovagal reaction typically is brought on by emotions of fear or pain such as having blood drawn, starting an intravenous infusion, or by gastrointestinal upset. Vasovagal reactions are caused by activity of involuntary (autonomic) nervous system, especially the vagus nerve, which releases hormones that slow the heart and widen the blood vessels. The vagus nerve controls the heart rate (slows it down). The vagus nerve also controls digestive tract function and senses activity in the digestive system. Thus, some people can have a vasovagal reaction from straining at a bowel movement or vomiting.

• Postural (orthostatic) hypotension is a sudden drop in blood pressure when an individual stands up from a sitting, squatting, or supine (lying) position. When a person stands up, gravity causes blood to settle in the veins in the legs, so less blood reaches the heart for pumping, and as a result the blood pressure drops. The body normally responds automatically to the drop in blood pressure by increasing the rate at which the heart beats and by narrowing the veins to return more blood to the heart. In patients with postural hypotension, this compensating reflex fails to occur, resulting in symptomatic low blood pressure. Postural hypotension can occur in persons of all ages but is much more common among the elderly, especially in those on medications for high blood pressure and/or diuretics. Other causes of postural hypotension include dehydration, adrenal insufficiency (discussed later), prolonged bed rest, diabetes that has caused damage to the autonomic nerves, alcoholism with damage to the autonomic nerves, and certain rare neurological syndromes (for example, Shy-Drager syndrome) that damage the autonomic nerves.

• Another form of postural hypotension occurs typically in young healthy individuals. After prolonged standing, the individual's heart rate and blood pressure drops, causing dizziness, nausea, and often fainting. In these individuals, the autonomic nervous system wrongly responds to prolonged standing by directing the heart to slow down and the veins to dilate.

• Micturition syncope is a temporary drop in blood pressure and loss of consciousness brought about by urinating. This condition typically occurs in elderly patients and may be due to the release by the autonomic nerves of hormones that lower blood pressure.

• Adrenal insufficiency, for example, due to Addison's disease, can cause low blood pressure. Addison's disease is a disorder in which the adrenal glands (small glands next to the kidneys) are destroyed. The destroyed adrenal glands can no longer produce sufficient adrenal hormones (specifically cortisol) necessary to maintain normal bodily functions. Cortisol has many functions, one of which is to maintain blood pressure and the function of the heart. Addison's disease is characterized by weight loss, muscle weakness, fatigue, low blood pressure, and, sometimes, darkening of the skin.

• Septicemia is a severe infection in which bacteria (or other infectious organisms such as fungi) enter the blood. The infection typically originates in the lungs (as pneumonia), bladder, or in the abdomen due to diverticulitis or gallstones. The bacteria then enter the blood where they release toxins and cause life-threatening and profound low blood pressure (septic shock), often with damage to several organs.

• Anaphylaxis (anaphylactic shock) is a potentially fatal allergic reaction to medications such as penicillin, intravenous iodine used in some x-ray studies, foods such as peanuts, or bee stings (insect stings). In addition to a severe drop in blood pressure, individuals may also experience hives, wheezing, and a swollen throat with difficulty breathing. The shock is caused by enlargement of blood-containing blood vessels and escape of water from the blood into the tissues.

How is low blood pressure diagnosed and evaluated?

In some individuals, particularly relatively healthy ones, symptoms of weakness, dizziness, and fainting raise the suspicion of low blood pressure. In others, an event often associated with low blood pressure, for example a heart attack has occurred to cause the symptoms.

Measuring blood pressure, sometimes in both the lying (supine) and standing positions usually is the first step in diagnosing low blood pressure. In patients with symptomatic low blood pressure, there often is a marked drop in blood pressure upon standing, and patients may even develop orthostatic symptoms. The heart rate often increases greatly. Once low blood pressure has been identified as the cause of symptoms, the goal is to identify the cause of the low blood pressure. Sometimes the causes are readily apparent (such as loss of blood due to trauma, or sudden shock after receiving x-ray dyes containing iodine). At other times, the cause may be identified by testing:

• CBC (complete blood count). CBC may reveal anemia from blood loss or elevated white blood cells due to infection.

• Blood electrolyte measurements may show dehydration and mineral depletion, renal failure (kidney failure), or acidosis (excess acid in the blood).

• Cortisol levels can be measured to diagnose adrenal insufficiency and Addison's disease.

• Blood and urine cultures can be performed to diagnose septicemia and bladder infections, respectively.

• Radiology studies, such as chest x-rays, abdominal ultrasounds, and computerized tomography (CT or CAT) scans may detect pneumonia, heart failure, gallstones, pancreatitis, and diverticulitis.

• Electrocardiograms (EKG) can detect abnormally slow or rapid heart beats, pericarditis, and heart muscle damage from either previous heart attacks or a reduced supply of blood to the heart muscle that has not yet caused a heart attack.

• Holter monitor recordings are used to diagnose intermittent episodes of abnormal heart rhythms. If abnormal rhythms occur intermittently, a standard EKG performed at the time of a visit to the doctor's office may not show the abnormal rhythm. A Holter monitor is a continuous recording of the heart's rhythm for 24 hours that often is used to diagnose intermittent episodes of bradycardia or tachycardia.

• Patient-activated event recorder. If the episodes of bradycardia or tachycardia are infrequent, a 24-hour Holter recording may not capture these sporadic episodes. In this situation, a patient can wear a patient-activated event recorder for up to four weeks. The patient presses a button to start the recording when he or she senses the onset of an abnormal heart rhythm or symptoms possibly caused by low blood pressure. The doctor then analyzes the recordings at a later date to identify the abnormal episodes.

• Echocardiograms are examinations of the structures and motion of the heart using ultrasound. Echocardiograms can detect pericardial fluid due to pericarditis, the extent of heart muscle damage from heart attacks, diseases of the heart valves, and rare tumors of the heart.

• Ultrasound examinations of the leg veins and CT scans of the chest can detect deep vein thrombosis and pulmonary embolism.

• Tilt-Table tests are used to evaluate patients suspected of having postural hypotension or syncope due to abnormal autonomic nerves. During a tilt-table test, the patient lies on an examining table with an intravenous infusion administered while the heart rate and blood pressure are monitored. The table then is tilted upright for 15 minutes to 45 minutes. Heart rate and blood pressure are monitored every few minutes. The purpose of the test is to try to reproduce postural hypotension.  Sometimes a doctor may administer epinephrine (Adrenalin, Isuprel) intravenously to induce postural hypotension.

How is low blood pressure treated?

Low blood pressure in healthy subjects without symptoms or organ damage needs no treatment. However, all patients with symptoms possibly due to low blood pressure should be evaluated by a doctor. (Patients who have had a major drop in blood pressure from their usual levels even without the development of symptoms also should be evaluated.) The doctor needs to identify the cause of the low blood pressure because treatment will depend on the cause. For example, if a medication is causing the low blood pressure, the dose of medication may have to be reduced or the medication stopped, though only after consulting the doctor. Self-adjustment of medication should not be done.

• Dehydration is treated with fluids and minerals (electrolytes). Mild dehydration without nausea and vomiting can be treated with oral fluids and electrolytes. Moderate to severe dehydration usually is treated in the hospital or emergency room with intravenous fluids and electrolytes.

• Blood loss can be treated with intravenous fluids and blood transfusions. Continuous and severe bleeding needs to be treated immediately.

• Septic shock is an emergency and is treated with intravenous fluids and antibiotics.

• Blood pressure medications or diuretics are adjusted, changed, or stopped by the doctor if they are causing low blood pressure symptoms.

• Bradycardia may be due to a medication. The doctor may reduce, change or stop the medication. Bradycardia due to sick sinus syndrome or heart block is treated with an implantable pacemaker.

• Tachycardia is treated depending on the nature of the tachycardia. Atrial fibrillation can be treated with oral medications, electrical cardioversion, or a catheterization procedure called pulmonary vein isolation. Ventricular tachycardia can be controlled with medications or with an implantable defibrillator.

• Pulmonary embolism and deep vein thrombosis is treated with blood thinners, intravenous initially with heparin, and oral warfarin (Coumadin) later.

• Pericardial fluid can be removed by a procedure called pericardiocentesis.

• Postural hypotension can be treated by increasing water and salt intake*, increasing intake of caffeinated beverages because caffeine constricts blood vessels, using compression stockings to compress the leg veins and reduce the pooling of blood in the leg veins, and in some patients, the use of a medication called midodrine (ProAmatine). The problem with ProAmatine is that while it increases blood pressure in the upright position, the supine blood pressure may become too high, thus increasing the risk of strokes. Mayo Clinic researchers found that a medication used to treat muscle weakness in Myasthenia gravis called pyridostigmine (Mestinon) increases upright blood pressure but not supine blood pressure. Mestinon, an anticholinesterase medication, works on the autonomic nervous system, especially when a person is standing up. Side effects include minor abdominal cramping or increased frequency of bowel movements. *Note: Increasing salt intake can lead to heart failure in patients with existing heart disease and should not be undertaken without consulting a doctor.

• Postprandial hypotension refers to low blood pressure occurring after meals. Ibuprofen (Motrin) or indomethacin (Indocin) may be beneficial.

• Vasovagal Syncope can be treated with several types of drugs such as beta blockers [for example, propanolol (Inderal, Inderal LA)], selective serotonin reuptake inhibitors [fluoxetine (Prozac), escitalopram oxalate (Lexapro), paroxetine (Paxil), sertraline (Zoloft), citalopram (Celexa), fluvoxamine (Luvox)], fludrocortisone (Florinef) (a drug that prevents dehydration by causing the kidney(s) to retaining water). A pacemaker can also be helpful when a patient fails drug therapy.

read more