Cardiovascular System Overview

Cardiovascular System

• The circulatory system's functions include carrying nutrients, oxygen, and other substances to cells, stopping bleeding, promoting healing, meeting increased exercise demands with increased blood flow, removing waste products, and regulating body temperature.
• It defends the body from microbes that cause disease.
• The circulatory system consists of the blood, heart, and blood vessels.

The Blood

• Blood consists of blood cells and plasma, primarily water.
• Red blood cells (RBCs), also called erythrocytes, give blood its red color due to hemoglobin.
• White blood cells (WBCs), also called leukocytes, protect the body from infection.
• Platelets (thrombocytes) are necessary for blood clotting.

The Heart

• The heart pumps blood through blood vessels to tissues and cells.
• It lies within the middle to lower part of the chest cavity, towards the left side.

Blood Vessels

• Arteries carry blood away from the heart. The aorta is the largest artery. Arterioles are the smallest branches of arteries.
• Capillaries are tiny blood vessels that pick up waste products from cells.
• Veins return blood to the heart. The inferior and superior vena cava are the two main veins.

Blood Flow Through the Heart

• A visual representation of the flow of blood through the heart in two minutes is shown.

Critical Thinking Questions

• Name three functions of the heart. The heart pumps blood throughout the body, regulates blood pressure, and helps maintain homeostasis.
• What is RBC and its function? RBC (red blood cell) transports oxygen to the tissues.
• What is WBC and its function? WBC (white blood cell) plays a crucial role in the immune system, fighting off infections.
• What is a blood vessel? A blood vessel is a tube that carries blood throughout the body.

Physical Changes as We Change

• The circulatory system weakens as we age.
• Arteries narrow and become less elastic.
• Rest is needed throughout the day and overexertion should be avoided.

Cardiovascular Disorders

• Cardiovascular disorders are a leading cause of death in Canada.
• These disorders involve the heart and blood vessels.

Hypertension

• Hypertension is a condition where blood pressure is abnormally high.
• Systolic pressure of 140 mm Hg or higher and diastolic pressure of 90 mm Hg or higher are considered signs of this condition.
• Consistent elevated readings are necessary for diagnosis.
• Causes include narrowed blood vessels, kidney disorders, head injuries, pregnancy complications, or tumors.
• Common symptoms include headaches, blurred vision, and dizziness.
• Possible complications include stroke, heart attack, kidney failure, or blindness.
• Treatments include medication, exercise, rest, smoking cessation, and a sodium-restricted diet.

Hypotension

• Hypotension is low blood pressure; systolic pressure of 90 mm Hg or below and diastolic pressure of 60 mm Hg or below.
• Chronic hypotension, lacking symptoms, is rarely dangerous.
• Sudden drops in blood pressure are serious; blood supply to the brain can be compromised, resulting in dizziness or lightheadedness, possible sudden drop in blood pressure most commonly occurs in individuals who are changing positions from lying to standing.
• Causes include hormonal problems, over-the-counter medication, heart failure, heart abnormalities, overheating, significant blood loss, low body temperature, dehydration.

Symptoms of Hypotension

• Dizziness/lightheadedness
• Reduced heart rate
• Unsteadiness/weakness
• Fatigue
• Pale or clammy skin
• Fainting

Complications of Hypotension

• Falls are a common complication.

Treatment for Hypotension

• Drink plenty of fluids.
• Eat a diet richer in salt.
• Regular exercise to help circulatory function.
• Be careful when standing up/changing positions.
• Avoid prolonged exposure to hot showers or baths.
• Avoid straining during bowel movements.

Coronary Artery Disease (CAD)

• Coronary arteries narrow and thicken (atherosclerosis).
• Heart muscle receives less blood.
• Fatty material accumulates in artery walls (narrowing).
• Blocked arteries may cause permanent heart damage.

Risk Factors for CAD

• Age (more common in older adults)
• Gender (more common in men)
• Lifestyle factors (lack of exercise, obesity, smoking, excessive alcohol, stress)
• High blood cholesterol
• Hypertension
• Family History of CAD
• Uncontrolled diabetes

Angina Pectoris

• Chest pain due to reduced blood flow to the heart.
• Occurs when the heart needs more oxygen, often from physical exertion.
• Triggered by extreme cold, emotional stress, heavy meals, alcohol, and smoking.
• Typical symptoms include chest pain, tightness, or pressure in the chest. Pain may radiate to other body parts, and the person might experience shortness of breath (dyspnea), paleness, feeling faint, and perspiration.

Treatment for Angina Pectoris

• Nitroglycerin (tablet, ointment, patch, or spray) is used to relieve pain.
• If no pain relief, seek emergency assistance immediately.

Myocardial Infarction (MI)

• MI (heart attack) is caused by obstructed blood flow to the heart muscle (lack of blood supply, ischemia).
• Atherosclerosis, or blood clots, commonly block arteries in the heart.
• Damaged heart areas can be small or large, sometimes fatally so.
• Sudden cardiac death can be a potential complication.

Treatment for MI

• Immediate emergency care is crucial.
• Efforts to relieve pain, stabilize vital signs with oxygen, and calm the patient are important.
• Gradually increase activities after recovery from MI.
• Cardiac rehabilitation program.
• Lifestyle changes.

Sudden Cardiac Arrest

• Loss of heart function resulting from an electrical disturbance leading to loss of breathing and consciousness.
• If not treated immediately, can result in death.
• CPR, defibrillator, and chest compressions can improve survival chances until emergency responders arrive.
• Conditions leading to sudden cardiac arrest include arrhythmias, coronary artery disease, myocardial infarction, and congenital heart disease.

Symptoms of Cardiac Arrest

• Sudden collapse
• Lack of pulse
• Absence of breathing
• Loss of consciousness

Congestive Heart Failure (CHF)

• Heart can't normally pump blood efficiently, causing a buildup of fluids in the body.
• Right-sided failure: Fluid backup in the veins, causing swelling in legs, ankles, and abdomen, congestion of the liver.
• Left-sided failure: Fluid build-up in the lungs, shortness of breath,
• Treatments include sodium restriction, oxygen administration, elevated Fowler's position, monitoring fluid intake/output, elastic stockings, and assistance with ambulation and transfers.

Arrhythmias

• Irregular heartbeats (skipped or extra beats).
• Not usually life-threatening, potentially dangerous.
• Pacemakers (implanted medical devices) monitor heart rate and stimulate the heart with small electrical impulses.

Phlebitis

• Inflammation of a vein, most often in the leg.
• Can be caused by infection, irritation, trauma, autoimmune diseases, or genetic conditions.
• Redness, warmth, pain, burning, and swelling at the affected site are indicators.

Thrombus

• A blood clot.
• In large vessels, blood flow reduction occurs.
• In small vessels, blood flow can be stopped.
• Formed due to various factors, including stroke, heart attack, clotting disorders, or prolonged inactivity.

Emboli/Pulmonary Embolism

• A blood clot that dislodges and travels through the bloodstream, possibly blocking a pulmonary artery.
• Difference between an embolus and pulmonary embolism lies in the clot's location and the potential for blocking important blood vessels or organs.

Critical Thinking Scenarios - Multiple Case Studies

Additional Notes

• The provided information is a summary of a presentation, not comprehensive information for cardiovascular health. Consult with healthcare professionals for accurate and personalized advice