WEEK 4 Perfusion Flashcards
Perfusion problems (25 cards)
Define Perfusion
Perfusion is a fundamental physiological process that ensures every cell, tissue, and organ in the body receives an adequate blood supply.
perfusion is essential to?
- Providing oxygen to body tissues for cellular respiration.
- Supplying essential nutrients, including glucose and electrolytes, required for cellular functions.
- Removing metabolic waste products, such as carbon dioxide and lactic acid.
- Carrying hormones and signalling molecules to target tissues.
- Distributing heat to maintain body temperature.
- Transporting immune cells to sites of infection and injury.
What is hyperfusion?
Insufficient blood flow to meet the body’s demands. It can result from conditions like atherosclerosis, thrombosis, or shock. Infarction refers to the death of tissue, usually caused by a lack of blood supply.
It occurs when the blood flow to a specific area is blocked, leading to oxygen and nutrient deprivation. Without a timely restoration of blood flow, the affected tissue begins to die. Infarction can occur in various organs and tissues throughout the body
What is cardiac ischemia?
This occurs when the blood flow to the heart muscle is reduced, often due to coronary artery disease.
It can lead to chest pain or discomfort, known as angina, and if severe and prolonged, it can result in a heart attack
What is Cerebral Ischemia
This type of ischemia affects the brain.
It can be caused by a blood clot blocking a cerebral artery (ischemic stroke) or a temporary reduction in blood flow (transient ischemic attack or TIA).
What is Peripheral Ischemia
This involves reduced blood flow to the limbs, usually the legs.
Peripheral Vascular Disease (PVD) is a common cause, and it can lead to pain, cramping, and difficulty walking.
What is Myocardial Infarction (MI)
Myocardial infarction (heart attack) occurs when there is a blockage in the coronary arteries, leading to inadequate blood supply to a part of the heart muscle.
This can result in damage or death of the heart tissue.
What is Cerebral Infarction
This refers to the death of brain tissue due to a lack of blood supply, often caused by a blood clot in a cerebral artery.
Cerebral infarction is commonly associated with ischemic strokes.
What is Pulmonary Infarction
This occurs when there is a blockage in the pulmonary arteries, leading to inadequate blood supply to a part of the lungs.
It can be associated with conditions such as pulmonary embolism.
What is Renal Infarction
Involves the death of tissue in the kidneys due to a blockage in the renal arteries.
What is Hyperperfusion (Congestion)
Excessive blood flow or impaired venous drainage, often seen in conditions like congestive heart failure.
What is Tissue Hypoxia
Inadequate oxygen supply to tissues, leading to cell damage or death. Conditions like acute respiratory distress syndrome (ARDS) can cause tissue hypoxia.
What is Thrombosis and Embolism
Blood clots (thrombi) or emboli (clot fragments) can obstruct blood vessels, leading to local perfusion problems.
Define Vasospasm
Sudden constriction of blood vessels, reducing blood flow. Vasospasm can be seen in conditions like Raynaud’s disease.
What is Peripheral Vascular Disease?
Conditions like peripheral artery disease (PAD) can result in reduced blood flow to the extremities.
What is Coronary Artery disease/ Ischemic Heart Disease (IHD)
Coronary Artery disease, is a common cardiovascular disorder characterized by the narrowing and blockage of the coronary arteries, which supply oxygen and nutrients to the heart muscle. The pathophysiology of CAD involves a complex interplay of various factors and processes.
What is Atherosclerosis?
The primary underlying factor in CAD is atherosclerosis, a chronic inflammatory condition. It begins with the accumulation of fatty deposits, mainly low-density lipoprotein (LDL) cholesterol, within the inner lining (endothelium) of coronary arteries. These deposits, called plaques, contain cholesterol, inflammatory cells (macrophages), and smooth muscle cells.
Atherosclerotic plaques can grow over time and may become unstable. Vulnerable plaques have thin fibrous caps and a lipid-rich core. They are more prone to rupture. Plaque rupture exposes the underlying tissue to the bloodstream, leading to platelet aggregation and thrombus (clot) formation.
If a plaque rupture leads to the formation of a thrombus that partially or completely obstructs a coronary artery, it can result in ACS, which includes unstable angina, non-ST-segment elevation myocardial infarction (NSTEMI), or ST-segment elevation myocardial infarction (STEMI).
What role does the mechanism of CAD in Vasoconstriction and Reduced Oxygen Supply play?
In addition to plaque rupture, other factors like vasospasm (sudden constriction of coronary arteries) and microvascular dysfunction can further reduce blood flow and oxygen supply to the heart muscle.
What role does Endothelial Dysfunction play in CAD?
The endothelium, which lines the coronary arteries, plays a critical role in maintaining vascular health. In CAD, chronic exposure to risk factors like smoking, high blood pressure, and diabetes can lead to endothelial dysfunction.
Dysfunction of the endothelium results in decreased production of nitric oxide, a molecule that helps relax and dilate blood vessels, leading to vasoconstriction and reduced vasodilation capacity.
What is Coronary syndrome?
Coronary syndrome refers to a spectrum of conditions that involve the coronary arteries, the blood vessels that supply the heart muscle with oxygen and nutrients. The two primary conditions within this spectrum are unstable angina and myocardial infarction (heart attack). Both of these conditions are related to atherosclerosis, the build up of plaque in the coronary arteries.
Define unstable angina
Unstable angina is a type of chest pain that is more severe or occurs more frequently than typical angina. It is considered unstable because it can happen at rest, during minimal physical activity, or with increasing intensity. Unlike stable angina, the pain associated with unstable angina is not easily relieved by rest or medication. Unstable angina is a serious condition and is often considered a precursor to a heart attack.
Define Myocardial Infarction (MI or Heart Attack)
Myocardial infarction occurs when there is a sudden and complete blockage of blood flow to a part of the heart muscle. This blockage is typically due to the rupture of a plaque in a coronary artery, leading to the formation of a blood clot. The lack of blood flow can cause damage or death to the heart muscle. Symptoms of a heart attack include chest pain or discomfort, shortness of breath, nausea, and pain or discomfort in the arms, jaw, neck, or back.
Define Hypertension
Hypertension, commonly known as high blood pressure, is a chronic medical condition characterized by persistently elevated blood pressure levels. It is a multifactorial disorder with a complex pathophysiology involving various physiological systems.
Define Vascular Resistance
One of the primary mechanisms of hypertension is increased peripheral vascular resistance, which refers to the resistance the blood encounters as it flows through the arteries. Elevated resistance can result from structural changes in the blood vessels, such as arteriosclerosis or atherosclerosis, which lead to narrowed and stiffened arteries.
