Blood pressure-diseases and disorders

Hypertension is the most common blood pressure-related disease. According to the Centers for Disease Control and Prevention (CDC), about 45% of adults in the United States have hypertension. The following sections describe hypertension, hypotension, postural orthostatic tachycardia syndrome, and shock.

Hypertension

Hypertension (HTN) is high blood pressure. HTN occurs when the force of the blood pushing against the artery wall is elevated. There are three types of hypertension:

• Primary hypertension (or essential hypertension): The most common type with no identifiable cause; develops with age.
• Secondary hypertension: High blood pressure is caused by another disease, condition, or medication. If the disease is treated or the medication is removed, the high blood pressure resolves.
• Malignant hypertension: Very high blood pressure that causes organ damage.

Hypertension has many causes:

• Genetics: Hypertension tends to run in families.
• Environmental factors: High-sodium diet, alcohol, smoking, lack of exercise, obesity, and some medications can lead to hypertension.
• Kidney fluid and salt balances: The kidney regulates the electrolyte and water balance in the body. Kidney disease can lead to increased blood volume, which leads to hypertension.
• Renin-angiotensin-aldosterone system: A complex system that makes angiotensin, which constricts blood vessels. It also makes aldosterone, which affects kidney function and leads to increased blood volume. Both can cause hypertension.
• Sympathetic nervous system: Involved with blood pressure regulation.
• Changes in blood vessels: Loss of elasticity in the walls can lead to hypertension.

Hypertension has no symptoms. The only sign is a high blood pressure reading. However, it can cause serious problems, including stroke, heart attack, heart failure, and kidney failure.

Blood pressure is measured and recorded as two numbers. The top number is the systolic pressure, or the blood pressure during a heartbeat. The bottom number is the diastolic pressure, or the blood pressure when the heart rests. Blood pressure is measured in millimeters of mercury (mm Hg). Treatment involves a low-salt or heart-healthy diet, maintaining a healthy weight, stopping smoking, exercising, limiting alcohol intake, and developing healthy strategies to cope with stress. Medications may also be used:

• Diuretics (“water pills”), which help the kidneys pull extra water and sodium from the blood, thus reducing blood volume
• Angiotensin II receptor blockers (ARBs), angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers (CCBs), and alpha-blockers, which relax blood vessels, thus reducing blood pressure

Hypotension

Hypotension is lower than normal blood pressure. When the blood pressure is lower than normal, the heart, brain, and other organs are not getting enough blood. A drop of as little as 20 mm Hg can cause problems for some people.

Severe hypotension can be caused by a sudden loss of blood, severe infection, heart attack, or severe allergic reaction (anaphylaxis). Here are some additional causes of hypotension:

• Orthostatic (postural) hypotension, caused by a sudden change in body position, such as moving from sitting to standing
• Postprandial orthostatic hypotension, caused by eating
• Neurally mediated hypotension (NMH), which occurs when standing for a long time
• Medications, such as antianxiety drugs, antidepressants, and diuretics
• Drinking alcohol, heart failure, dehydration, and arrhythmias

Signs and symptoms of hypotension include blurry vision, confusion, dizziness, fainting, lightheadedness, nausea, vomiting, sleepiness, and weakness.

Besides a medical history, the provider will perform a physical exam. Laboratory tests, such as blood cultures, a** complete blood count (CBC),** and a urinalysis, might be done. An ECG and x-rays can also be done. Treatment depends on the cause of hypotension. With symptoms of hypotension, the patient should sit or lie down immediately and raise the feet above heart level. Medication dosages may be adjusted. Wearing compression stockings can prevent pooling of blood in the legs, keeping more blood in the upper body.

Postural Orthostatic Tachycardia Syndrome

Postural orthostatic tachycardia syndrome (POTS) is estimated to affect 1 million to 3 million Americans and can occur at any age, although it commonly affects females between 15 and 50 years of age. POTS is considered a dysautonomia, an abnormal condition of the autonomic nervous system (ANS). The ANS does not control the blood pressure or heart rate when a person is standing up.

Many times, the underlying cause of a person’s POTS is unknown. Conditions that cause or are associated with POTS include autoimmune diseases, diabetes, infections (e.g., mononucleosis, Epstein-Barr virus, Lyme disease), multiple sclerosis, trauma, and vitamin deficiencies. The signs and symptoms can vary but may include hypovolemia (low blood volume), tachycardia, and orthostatic (postural) hypotension. Other symptoms include the following:

• Fatigue, exercise intolerance, nausea, headaches, and poor concentration
• Lightheadedness, blurred vision, syncope, heart palpitations, chest pain, and shortness of breath
• Cold or painful extremities (fingers and toes)
• Fainting with blood draws (phlebotomy) or deep breathing

For some people, the symptoms are mild and do not interfere with daily activity. Others experience significant symptoms that interfere with eating, moving, bathing, and working. About 25% of patients with POTS are disabled and cannot work.

Diagnostic testing for POTS includes the following:

• Tilt table test: A patient is strapped to a table; gradually, the table is tilted into the upright position, and the patient is monitored for the effects of the position changes.
• Orthostatic vital signs: Blood pressure and heart rate are obtained as the patient reclines, sits, and stands. In many cases, the blood pressure drops, and the heart rate increases.

Orthostatic (postural) hypotension occurs when there is a decrease in blood pressure within 3 minutes of standing up. The systolic blood pressure drops 20 or more mm Hg, and the diastolic blood pressure decreases 10 or more mm Hg. Treatment varies and may include medications to regulate the heart rate and blood pressure. Drinking plenty of fluids (2 to 3 L per day); eating a high-salt, low-carbohydrate diet; exercise; and compression stockings may also be encouraged as part of the treatment.

Shock

Shock usually happens with a serious injury and can be life threatening. There are several types of shock:

• Anaphylactic: Severe allergic reaction; caused by exposure to an allergen (e.g., insect bites/stings, food allergy, drug allergy)
• Cardiogenic: Inability of the damaged heart to pump blood effectively; caused by a heart attack, arrhythmias, pulmonary embolism, or congestive heart failure
• Hypovolemic: Excessive loss of blood or body fluids from internal or external hemorrhage (bleeding); severe dehydration, burns, vomiting, or diarrhea
• Neurogenic: Peripheral vessels dilate due to a neurologic injury or disorder (e.g., spinal cord injury)
• Septic: Overwhelming infection; caused by bacteria, fungi, and rarely viruses

The following responses are signs and symptoms of shock:

• Weak, rapid pulse and rapid, shallow respirations
• Changes in the level of consciousness: confusion, lack of alertness, loss of consciousness
• Dizziness, lightheadedness, or faintness
• Sweaty, pale skin; cool hands and feet; bluish lips and fingernails
• Reduced or no urine output

Shock is diagnosed based on the history, exam, and vital signs of the patient. If time allows, additional testing may be done to identify the cause. The goals of medical treatment include increasing the cardiac output and blood pressure with medications, blood transfusions, and IV fluids. Additional treatments address the cause of the shock.

Blood diseases and disorders

These are some common signs and symptoms of blood diseases and disorders:

• Fatigue, weakness, pale skin, lightheadedness, and shortness of breath (SOB)
• Bruising and bleeding
• Fever and weight loss
• A deficiency in WBCs (leukopenia) or an elevated number of WBCs (leukocytosis)
• A deficiency of RBCs (anemia) or an elevated number of RBCs (erythrocytosis)
• A deficiency of platelets (thrombocytopenia) or an elevated number of platelets (thrombocytosis)

The following sections describe blood diseases and disorders.

Anemia

Anemia is a common blood disorder. It occurs when the blood does not have enough healthy red blood cells or enough hemoglobin, which carries oxygen to the rest of the body. TABLE 25.8 presents the types of anemia, along with their etiologies and treatments.

Signs and symptoms include weakness, fatigue, pale skin, arrhythmias, SOB, dizziness, lightheadedness, cold hands and feet, headache, and chest pain.

A physical exam and a complete blood count (CBC) will be done. Additional tests may be done to rule out or confirm the type of anemia.

Hemophilia

Hemophilia is a genetic bleeding disorder that can lead to spontaneous bleeding. About 20,000 males in the United States live with the disorder. There are two types of hemophilia:

• Hemophilia A, or classic hemophilia: Caused by a lack of or decrease in clotting factor VIII
• Hemophilia B, or Christmas disease: Caused by a lack of or decrease in clotting factor IX

Hemophilia is caused by a mutation in a gene that provides information to make clotting factor proteins needed for making a blood clot. Because the mutation is on the X chromosome, a male with the mutation will have the disease. A female must have two X chromosomes with the mutation to have the disease. She will be a carrier of hemophilia if she just has one X chromosome with the mutation. Signs and symptoms include bleeding within the joints, skin, mouth, nose, and gums. Blood can be in the urine or stool. Bleeding can occur after surgery or injury. Complications include chronic joint disease and pain, seizures, paralysis, and possibly death.

If hemophilia runs in the family, the provider will test the male newborn. Blood clotting tests are performed, and if the results are abnormal, clotting factor tests (factor assays) will be done. Treatment consists of infusing commercially prepared factor concentrates as prophylaxis (prevention) or when bleeding occurs.

Idiopathic Thrombocytopenic Purpura (ITP)

Idiopathic thrombocytopenic purpura is also called immune thrombocytopenia and immune thrombocytopenic purpura. ITP is a rare autoimmune disease that results in the destruction of platelets.

The immune system produces antibodies that destroy platelets, thus causing ITP. In children, ITP sometimes occurs after a viral infection. In adults, ITP is a chronic disease that can occur after a viral infection, pregnancy, or infection with Helicobacter pylori. This disease can cause abnormally heavy menses, petechial rash (a rash with pinpoint red spots), easy bruising, nosebleeds, or bleeding.

After the physical exam, the provider will order a CBC to check the patient’s platelet level and a platelet antibody blood test. A biopsy or bone marrow aspiration may also be done. Treatment for adults consists of steroids and immunosuppressant medications, high-dose immune globulin infusions, drugs to stimulate the bone marrow, and a splenectomy.

Leukemia

Leukemia is a cancer of the blood-forming tissues, such as the bone marrow and the lymphatic system. The bone marrow produces abnormal white blood cells. Leukemia is classified as either acute or chronic. The secondary classification of leukemia is the type of white blood cell affected by the disease.

Signs and symptoms of Leukemia can include weakness, fever, shortness of breath, weight loss, rib pain, bruising, and painless lumps in the underarm, neck, and stomach. The exact cause of leukemia is unknown, but scientists believe it is a combination of genetics and environmental factors. Risk factors for leukemia include prior cancer treatments, genetic disorders, exposure to certain chemicals, family history of leukemia, and a history of smoking. After the physical examination, a CBC will be ordered. A specific type of WBC will be elevated, depending on the type of leukemia. A bone marrow biopsy may also be done.

Treatment for acute leukemia is more aggressive and consists of chemotherapy, radiation, and in some cases, a splenectomy. With chronic leukemia, as the disease worsens, the patient may receive chemotherapy and radiation. Biological therapy can also be used for leukemia. It boosts the body’s natural ability to fight cancer. In addition, targeted therapy may be used, which uses substances that fight cancer cells but do not harm normal cells.