Chapter 24 - Alterations in Cardiovascular Function Flashcards
What is a varicose vein?
a vein where blood has pooled, producing distended and palpable vessels
What 2 things cause varicose veins?
- trauma that damages valves
- gradual distention by gravity
How do vein valves get damaged?
increased pressure and blood volume due to the pressure of gravity
Which veins usually become varicose veins?
saphenous veins of the legs
Varicose veins: __________ remodel the vessel wall
enzymes
When varicose veins swell from pressure, what is pushed through the vessel wall?
plasma
Why does standing for long periods of time put one at risk for varicose veins?
it diminishes the action of muscle pump
What are 4 other risk factors for varicose veins
-age
-obesity
-genetics
-pregnancy
-previous leg injury
What is the non-invasive treatment for varicose veins?
-elevate legs
-compression stockings
What is the invasive treatment for varicose veins?
surgical ligation
What is surgical ligation?
tying up the blood vessel
What is chronic venous insufficiency?
inadequate venous return over an extended period
What are the symptoms of chronic venous insufficiency?
-edema of lower extremities
-hyperpigmentation of ankle and feet skin
Poor circulation, and thus reduced oxygen cells leads to ____________
necrosis
What is a risk of chronic venous insufficiency?
infection
reduced __________ makes surgery a risk
circulation
Venous stasis ulcers is an infection that occurs due to ______ __________ in veins
poor circulation
Venous stasis ulcers result from impaired oxygen delivery that leads to __________
necrosis
What is a thrombus?
a blood clot that remains attached to the vessel wall
What is a thromboembolism?
a detached thrombus
Why are venous thrombi more common that arterial thrombi?
flow and pressure are lower in veins
Thrombi occur more often where?
lower extremities
What is the the Virchow triad?
the 3 factors that promote Deep Venous Thrombosis (DVT)
What are the Virchow triad?
- venous stasis (immobility, age, heart failure)
- venous endothelial damage
- hyper-coagulable states
What is a hyper-coagulable state?
increased tendency of blood to thrombose
What causes a hyper-coagulable state?
-pregnancy
-oral contraceptives
-heredity
What causes a venous obstruction?
accumulation of clotting factors and platelets near a venous valve
With thrombus formation, _________ promotes further platelet aggregation
inflammation
Obstruction creates __________ edema and possible ulceration of limb
extremity
Ulceration of Limb
break on the skin surface
Most thrombus dissolve without treatment but others can be treated with ________________
anticoagulants
What are some examples of anticoagulants?
aspirin and warfarin
How are venous thrombi diagnosed?
doppler ultrasonography
What is a doppler ultrasound?
a non-invasive test that estimates blood flow through vessels by bouncing high-frequency sound waves
What is superior vena cava (SVC) syndrome?
the progressive occlusion of the superior vena cave leading to venous distention
Where does SVC syndrome venous distension affect?
upper extremities and head
Bronchogenic cancer is the cause of _____% of SVC syndrome cases
75%
What results from SVC syndrome?
-edema
-venous distension in upper extremities and face
Symptoms of SVC Syndrome
-tightness of shirt collars and necklaces
-headache
-visual disturbances
How is SVC syndrome diagnosed?
-chest x-ray
-CT
-MRI
What is hypertension?
consistent elevation of systemic arterial blood pressure
_______ and _______ pose risk for hypertension
age and diabetes
What two mechanisms are essential for maintaining a proper blood pressure?
exercise and proper nutrition
Primary hypertension can be essential or __________
idiopathic
95% of cases are _____________ hypertension
primary
What causes secondary hypertension?
a separate underlying disorder
___% of cases involve secondary hypertension
5%
What is malignant hypertension?
rapidly progressing hypertension
Malignant hypertension involves a systolic BP above ______ mmHg and a diastolic BP above ______ mmHg
180; 120
Malignant hypertension can lead to ________ and _________ complications
systemic; organ
Malignant hypertension is considered…
a medical emergency
What is a normal blood pressure value?
systolic <120 and diastolic <80
What is an elevated blood pressure value?
systolic 120-129 and diastolic <80
Stage 1 Hypertension value:
systolic 130-139 OR diastolic 80-89
Stage 2 Hypertension value:
systolic ≥140 OR diastolic ≥90
What are the values of a hypertensive crisis?
systolic >180 and/or diastolic >120
Primary hypertension is caused by a combination of genetic and ____________ factors
environmental
Epigenetics
how behaviours and environment affect gene function
Hypertension results from sustained peripheral ___________ and/or an increase in ________ ________
resistance; blood volume
What two primary factors contribute to primary hypertension?
-the sympathetic nervous system
-RAAS
How does increased SNS stimulation increase blood pressure?
increased HR, increased contractibility, systemic vasoconstriction
What does RAAS stand for?
renin-angiotensin-aldosterone system
How does aldosterone increase bp?
it increases Na+ reabsorption to increase blood volume (water follows Na+)
How does angiotensin II increase bp?
it increases vasopressin (ADH) which increases vasoconstriction
What is sclerosis?
abnormal hardening of body tissue
What is arteriosclerosis?
a generic term for vascular disease that causes thickening and inelasticity of arteries
Atherosclerosis is a dominant pattern of __________
arteriosclerosis
What is atherosclerosis?
formation of fatty plague with a core rich in lipids
Athera is the Greek word for ______ and it means…
athero; porridge
Treatment for hypertension begins with lifestyle modifications such as:
-diet
-exercise
-stopping smoking
-weight loss
What are two advances treatments for hypertension?
-diuretics
-angiotensin II blockers
Orthostatic hypotension is defined as a decrease in systolic bp of ___ mmHg or a decrease in diastolic BP of ___ mmHg within ___ minutes of standing
20; 10; 3
What adjustments are normally made to maintain BP when standing?
-baroreceptors
-vasoconstriction
-heart rate
What are the signs and symptoms of orthostatic hypotension?
-dizziness
-vision loss
-reduced brain blood flow
Is there a curative Tx for orthostatic hypotension?
no
What are ways to manage orthostatic hypotension?
-increased fluid and salt intake
-thigh high stockings
What is an aneurysm?
a localized dilation of a vessel wall
An aneurysm involves all ______ layers of the vessel wall
three
Aneurysms progressively _______ the vessel wall
weaken
What is the most common vessel to suffer an aneurysm?
aorta - a region of constant high pressure stress
What are 3 risk factors for aneurysm?
-smoking
-genetics
-diet
What are the 3 layers of the blood vessel from innermost to outermost?
tunica intima, tunica media, tunica adventita
What is an embolsim?
a vessel obstruction by an embolus
What is an embolus?
a bolus of matter circulating in the blood stream
An embolism can can consist of a dislodged _______, aggregation of fat/_______ cells, or foreign substance
thrombus; cancer
An embolus travels in the blood stream until it reaches…
a vessel through which it can’t pass
An embolism causes ischemia and if not resolved can lead to infarction which is…
ischemia resulting in necrosis
What is thromboangiitis obliterans?
inflammation of peripheral arteries