Disorders of Blood flow and BP Flashcards
Ischemia is the
Reduction in arterial flow to a level that is insufficient to meet the oxygen demands of the tissue
inadequate blood supply
Infarction is an area of
Ischemic necrosis in an organ produced by occlusion of its arterial blood supply or venous drainage
obstruction of blood supply
Dyslipidemia is the imbalance of
Lipid components (triglycerides, phospholipids, cholesterol)
Atherosclerosis is the
Hardening of the arteries
Atherosclerosis is characterized by
The formation of fibrofatty lesions in the intimal lining of large and medium sized arteries
The risk factors of atherosclerosis are
Hypercholesterolemia (elevations in LDL cholesterol) **This is the major risk factor** ^^^ Smoking Obesity Hypertension Diabetes mellitus Physical inactivity Stressful life patterns Blood levels of C-reactive protein (CRP) Serum homocysteine levels
How does smoking cause atherosclerosis?
By damaging the endothelial tissue of the blood stream causing inflammation - allows for plaque build-up
What is CRP?
What does it implicate in atherosclerosis?
C-reactive protein is an acute-phase reactant protein of the inflammatory process
CRP has been noted within some atherosclerosis plaques - indicates inflammation in plaque formation
What is homocysteine?
How does it cause atherosclerosis?
It is an amino acid produced to break down proteins in the body
It inhibits elements of the anticoagulant cascade and is associated with endothelial damage leading to inflammation
List the three types of lesions associated with atherosclerosis
Fatty streak
Fibrous atheromatous plaque
Complicated lesion
Fatty streaks are
Thin, flat, yellow lines that become thicker and slightly elevated
Fatty streaks consist of
Macrophages and smooth muscle cells (SMCs) that have become distended with lipids to form foam cells
Who do fatty streaks affect?
Everyone; they present in children and increase in number until 20 years of age
Fibrous atheromatous plaque is gray to pearly white because
Macrophages ingest and oxidize accumulated lipoprotein
Over time, the fatty streaks grow and proliferate into the smooth muscle layer
What are the main three problems that fibrous atheromatous plaque causes
Can occlude the vessel
Can lead to a thrombus (blood clot)
Can reduce the blood flow
Complicated atherosclerotic lesions are caused when
What is produced?
Fibrous plaque breaks open
Hemorrhage
Ulceration
Scar tissue deposits
What is the most important complication of atherosclerosis?
Thrombosis (blood clot blocks vein or artery)
Hyperlipidemia may also play a role in
Atherosclerotic lesions
Activated macrophages release
Free radicals that oxidize LDL
The development of atherosclerotic lesions is a
It involves
Progressive process
Endothelial cell injury
Migration of inflammatory cells
SMC proliferation and lipid deposition
Gradual development of he atheromatous plaque with a lipid core
Endothelial cell injury is caused by
Smoking
Elevated LDL levels
Immune mechanisms
Mechanical stress associated with hypertension
In the migration of inflammatory cells, monocytes adhere to ___ then become ___ and then turn into ___
Endothelium
Macrophages that engulf lipoproteins
Foam cells
Lipid accumulation and SMC proliferation is due to
Growth factors
Within lipid accumulation and SMC proliferation, what happens to foam cell macrophages?
They die, depositing necrotic cellular debris an lipids within the vascular wall
The plaque structure is vulnerable and can
This would lead to
Rupture
Ulcerate
Erode
Hemorrhaging to the plaque or thrombotic occlusion of the vessel lumen
Clinical manifestations of atherosclerosis
Manifestations depend onf
There are no symptoms until the artery is severely narrowed or totally obstructed
The vessels involved
the extend of vessel obstruction
What organs/tissues are most frequently involved in atherosclerosis?
Arteries supplying the heart, brain, kidneys, lower extremities, and small intestine
Acute arterial occlusion is the
Commonly caused by
Sudden interruption to blood flow
Thrombus - blood clot
Most emboli start in
The heart
Thrombi arise from
The erosion/rupture of a fibrous cap or an arteriosclerotic plaque
Clinical manifestations of acute arterial occlusion depend on
The artery involved and the adequacy of collateral circulation
What are the 7 P’s of acute arterial occlusion?
Pistol shot (acute onset) Pallor Polar (cold) Pulselessness Pain Paresthesia Paralysis
Atherosclerotic occlusive disease is a
Caused by
Peripheral artery disease
Atherosclerosis
Atherosclerotic occlusive disease is common in the
Lower extremities
Symptoms of atherosclerotic occlusive disease show up
Symptoms occurs with
Gradually
50% narrowing
The primary symptom of atherosclerotic occlusive disease is
Intermittent claudication (muscle pain that occurs when you’re active and stops when you rest)
Other signs of ischemia are
Atrophic changes (body tissue or organ atrophied)
Thinning of skin and subcutaneous tissues of the lower leg
Reduced size of leg muscles
Thromboangiitis is also called
Buerger disease
Thromboangiitis is an
Inflammatory arterial disorder that causes thrombus formation
What/where does thromboangiitis affect?
Medium sized arteries in the foot and lower leg
What is the cause of thromboangiitis?
Unclear
But smoking is involved (smoking causes everything)
What the symptoms of thromboangiitis?
Pain (even present at rest in severe cases)
Intermittent claudication in arch of foot/digits
Increased sensitivity to cold
Cyanotic extremities in dependent position (can be reddish/blue in nondependent positions)
Skin becomes thin, shiny, suffered hair growth and nutrition
Raynaud disease/phenomenon is the
Vasospasm of arteries and arterioles (usually fingers
What causes Raynaud disease?
Raynaud phenomenon?
No one knows
Due to other disorders/diseases
Raynaud disease is brought on by
The cold or strong emotions
What are manifestations of Raynaud disease/phenomenon?
Blanching of the extremities
> Primarily fingers
> Cold to the touch, can become red once spasm ends
An aneurysm is an
Abnormal localized dilation of a blood vessel
Aneurysms are most common in the
Aorta
What are the two kinds of aneurysms?
True and False
aneurysms can be hipster too
A true aneurysm is
Bounded by a complete vessel wall
> Blood remains within the vascular compartment
an abnormal dilation of an artery due to a weakened vessel wall
A false aneurysm is a
Localized dissection/tear in the inner wall of the artery with formation of an extravascular hematoma that causes vessel enlargement
when a blood vessel wall is injured and the leaking blood collects in the surrounding tissue
What is the most serious complication of an aortic aneurysm?
Rupture (then DEATH)
Causes of thoracic aortic aneurysm and abdominal aortic aneurysm
Atherosclerosis and degeneration of vessel media
Hypertension
Smoking
List symptoms of a thoracic aortic aneurysm
Substernal, back, and neck pain Dyspnea Stridor or brassy cough Hoarseness Distention of neck veins Edema of the face and neck
may be asymptomatic until rupture
What are symptoms of an abdominal aortic aneurysm?
Calcification
Pain (varies from mild mid-abdominal or lumbar discomfort to severe abdominal and back pain)
> pain from lower back to back of the legs
Erosion of vertebrae
Most abdominal aortic aneurysms are
What can be the first sign?
Asymptomatic
Pulsating mass
Aortic dissection is chronic or acute?
Acute - life threatening condition
If you had a patient with an aortic dissection, what would you expect to see?
Hemorrhage into the vessel wall with tearing to form a blood filled pocket
heart wall splits and blood pools between the layers
What are the causes of aortic dissection?
Conditions that weaken the elastic and smooth muscle layers of the aorta
What are the 2 risk factors of aortic dissection?
Hypertension
Degeneration of the medial layer of the vessel wall
You might see a patient with an aortic dissection as a complication of
Cardiac surgery
Catheterization
What is the major symptom of aortic dissection?
Abrupt excruciating pain (described as tearing or ripping)
In the early stages of an aortic dissection, BP is typically
Moderately or markedly elevated
In the later stages of an aortic dissection, BP and PR become
Unobtainable in on or both arms
Other manifestations of aortic dissection are
Syncope (fainting, LOC)
Hemiplegia (paralysis of one side of the body)
Paralysis of the lower extremities
Heart failure - when the aortic valve in involved
Veins move ___ from the body to the ___
Deoxygenated blood
Right side of the heart
What are the two mechanisms that prevent retrograde flow?
Valves and action of leg muscles
Varicose veins are
Dilated, tortuous veins of the lower extremities
What is the most common cause of varicose veins?
DVT (deep vein thrombosus)
You’re most likely to see varicose veins in ___ patients.
Female
There is a higher incidence of varicose veins in people who
Are obese or pregnant
> Increase intra-abdominal pressure which puts stress on saphenofemoral junction
Stand for long periods of time
> standing increases venous pressure and causes dilation/stretching of vessel wall
Clinical manifestations of varicose veins are
Aching in lower extremities and edema
In regards to varicose veins, prolonged exposure to increased pressure causes venous valves to
Become incompetent (no longer close properly) > reflux of blood causes further venous enlargement , pulling the valve leaflet apart
Chronic venous insufficiency is
Persistent venous hypertension in lower extremities
The causes of chronic venous insufficiency are
Increased venous hydrostatic pressure Incompetent valves in veins Deep vein obstructions Decreased skeletal muscle pump function Inflammatory processes Endothelian dysfunction Ineffective blood flow Retrograde blood flow
Chronic venous insufficiency presents with
Tissue congestion
Edema
Impaired tissue nutrition
Necrosis of subQ fat deposits - skin atrophy
Brown pigmentation of skin (due to hemosiderin deposits resulting from the breakdown of RBC)
Advanced stages:
Stasis dermatitis (shiny, bluish brown skin, poor healing)
Ulcers
Venous thrombosis is
Thrombus plus inflammation
Venous thrombosis is most common in
Lower extremities
Venous thrombosis can cause a
Pulmonary embolism
How can a DVT cause a PE?
By throwing a clot to the heart
Are DVT or SVT more common?
DVT
Venous thrombosis is associated with
Stasis of blood
Increased blood coagulability
Vessel wall injury
Virchow Triad
Examples of stasis of blood
Impaired cardiac function
Acute MI and congestive heart failure
Long airplane travel/extended sittin
Examples of increased blood coagulability
State of increased clot formation
Inherited disorders of factor V Leiden and prothrombin
Smoking
Birth control
Examples of vessel wall injury
Trauma and surgery
Infection or inflammation
Venous catheters
Many cases of venous thrombosis appear without
Symptoms
Venous thrombosis symptoms are related to
List symptoms
Inflammation
Pain Swelling Deep muscle tenderness Fever Malaise Elevated WBC Erythrocyte sedimentation
BP is closely regulated to ensure
Body tissues are perfused
Arteries don’t get damaged
Hypertensions is
Elevated BP
What are the two types of hypertension?
Primary - “essential” (no evidence of other diseases)
Secondary (due to another disease condition)
Non-modifiable risk factors of hypertension are
Age Gender Race Family history Genetics
Modifiable risk facts of hypertension are
Diet Levels of blood lipids Smoking and alcohol consumption Fitness and activity level Overweight/obesity Blood glucose control
Clinical manifestations of primary hypertension
Typically asymptomatic until long term effects on target-organ systems (kidneys, heart, eyes, blood vessels)
Secondary hypertension has 5 big causes
Renal hypertension
Disorders of adrenocortical hormones
Pheochromocytoma
Coarctation of the aorta
Oral contraceptive drugs
Which of the big 5 is the largest cause of secondary hypertension?
Renal hypertension
Renal hypertension is caused by
Reduced renal blood flow and activation of the renin-angiotensin-aldosterone mechanism
Disorders of adrenocortical hormones is
Hormonally induced renal retention of salt and water
Pheochromocytoma is a
Tumor of chromaffin tissue
> Contains sympathetic nerve cells that release catecholamine (most commonly located in the adrenal medulla)
Coarctation of the aorta is a
Congenital condition in which there is narrowing in the area of the arch of the aorta
Oral contraceptive drugs cause is
Largely unknown
> Probably cause is volume expansion
Increased perfusion pressure leads to
Damage of target organs
Increased intravascular pressure leads to
Damage of endothelial cells in vessels - increases the risk for atherosclerosis
Hypertension is a big risk factor for atherosclerosis because
It promotes plaque formation and rupture
Hypertension predisposes to
Coronary heart disease
Heart failure
Stroke
PAD
Hypertension causes increased workload of the
Left ventricle (heart pumps against high pressure in arteries)
Chronic hypertension can lead to
Nephrosclerosis (hardening of the walls of the small arteries of the kidney)
> > Glomerular perfusion is decreased
People with hypertension are more likely to experience what in regards to the brain
Dementia and cognitive impairment
Stroke
Hypertension can lead to what eye changes?
Microvascular changes in retina (retinopathy)
Orthostatic hypertension is when
BP drops after a person stands after sitting or lying down
Systolic BP drop of 20mmHg and/or diastolic BP drop of 10mmHg
With the BP of a patient with orthostatic hypertension, you’d expect to see what in regards to systolic and diastolic?
Systolic BP drop of 20mmHg and/or diastolic BP drop of 10mmHg
A patient with orthostatic hypertension would present with
May be asymptomatic or have dizziness and syncope
What causes orthostatic hypertension?
When moving to standing position, 500-700 ml shifts to lower part of body
> > Several normal body responses act to maintain blood pressure with this shift - Without those responses
Blood pools in lower extremities, meaning inadequate blood flow to brain, which causes symptoms
Contributing factors of orthostatic hypertension are
Effects of aging Reduced blood volume Bed rest and impaired mobility Drug induced hypotension Disorders of autonomic nervous system
Why do the effects of aging contribute to orthostatic hypertension?
There is increased arterial pressure instability and deficiencies in circulatory system
Why does reduced blood volume contribute to orthostatic hypertension?
There is just not enough blood circulating around (not enough oxygen when the person stands)
Why does bed rest and impaired mobility contribute to orthostatic hypertension?
Reduced plasma volume
Decreased venous tone
Failed peripheral vasoconstriction
Weakness of skeletal muscles that support veins
Why does drug induced hypotension contribute to orthostatic hypertension?
Antihypertensives
Antipsychotics
Why do disorders of the autonomic nervous system contribute to orthostatic hypertension?
Sympathetic stimulation increases heart rate and cardiac contractility, which causes constriction of peripheral arterioles and veins
» Diabetes mellitus and spinal cord injury puts people at risk.
