Lesson 1, Topic 1
In Progress

Blood Pressure–Related Diseases and Disorders

April 11, 2024

Learning Objective: Examine blood pressure–related diseases and disorders, including the signs, symptoms, etiology, diagnostic procedures, and treatments.
      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
Learning Objective: Describe hypertension, including the signs, symptoms, etiology, diagnostic procedures, and treatments.
      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). TABLE 25.7 lists the stages of blood pressure. 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
Learning Objective: Describe hypotension, including the signs, symptoms, etiology, diagnostic procedures, and treatments.
      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 the heart level. Medication dosages may be adjusted. Wearing compression stockings can prevent blood pooling in the legs, keeping more blood in the upper body.

Postural Orthostatic Tachycardia Syndrome
Learning Objective: Describe postural orthostatic tachycardia syndrome, including the signs, symptoms, etiology, diagnostic procedures, and treatments.
      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.


25.9 Critical Thinking Application
Rebecca and Lizzy are working with a patient who has been diagnosed with postural orthostatic tachycardia syndrome (POTS). Having never heard of POTS, Rebecca asks the patient to explain the disease. The patient explains that her blood volume is low. She needs to consume a lot of sodium and water to maintain her blood volume. The patient states that she faints with blood draws. Rebecca thanked the patient for her explanation. Why is it important for medical assistants to listen to their patients about their special needs?


Shock
Learning Objective: Discuss shock, including the signs, symptoms, etiology, diagnostic procedures, and treatments.
      Shock occurs when there is not enough blood and oxygen getting to the organs and tissues. It causes very low blood pressure.
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.