Cardiac - Class 2 - vessels Flashcards
What can happen if a thrombus forms over the atherosclerotic lesion in PAD? What does it cause?
Complete obstruction of blood flow can occur acutely, causing severe pain, loss of pulses, and skin colour changes in the affected extremity
What does hypertension result from?
It results from a sustained increase in peripheral resistance, an increase in blood volume, or both
Primary Hypertension Vs Secondary Hypertension?
Primary Hypertension – 92-95% of population – primary disease – disease is hypertension – no known cause
Secondary Hypertension – 5-8% of population – caused by underlying disease – underlying disease – possibly renal – causing hypertension
Causes of vascular diseases?
o Obstruction (Tend to create turbulence):
Thrombus - formation (blood clot attached to vessel wall)
Embolus - clot or foreign mass floating in circulation.
Compression by external forces such as tourniquet, cast, circular dressings, tumours, sustained pressure especially over bony prominences
Structural changes to the vessel
o Aneurysms
o Impaired venous valves
o Atherosclerosis (fatty deposits on the walls of the vessel
o Vasospasm - smooth muscle constricts due to local or neurally mediated reflex or disruption of other regulation mechanisms
Where do aneurysms commonly occur? Why?
Most commonly occur In the thoracic or abdominal aorta
The aortic is susceptible to aneurysm formation because of constant stress on the vessel wall and the absence of penetrating vasa vasorum in the media layer
vasospastic attacks – change in skin colour & sensation – causes pallor, numbness, sensation of coldness are symptoms of?
Raynaurd Phenomenon
What is Raynaud Phenomenon?
Attacks of vasospasm in the small arteries and arterioles of fingers (less common toes), circulation cut off until you get away from stimulus, warm hands up
What can complicated primary hypertension occur with?
Can occur with:
Chronic hypertension - normally controlled by medication – acute exacerbation that can no longer be controlled by medication,
Pregnancy
adrenal tumours
What causes Chronic venous insufficiency?
Valvular incompetence
Obesity
Inadequate venous return over a long period
Venous hypertension,
circulatory stasis,
and tissue hypoxia = remodeling of the skin – then ulceration
What is white coat syndrome?
This condition occurs when blood pressure readings at a health care provider’s office are higher than they are in other settings, such as at home. It’s called white coat hypertension because people who measure blood pressure sometimes wear white coats.
White coat syndrome – keep in mind patient anxiety – having them take their blood pressure at home or on an automated BP without a physician present
SNS- development and sustaining HTN?
SNS – development and sustaining HTN:
-Stress/Flight/Fight
1.)Epinephrine/Norepinephrine
2.)Beta 1 = increased heart rate and contraction force =increased BP
3.) Alpha 1 = peripheral vasoconstriction = increased BP
4.) Increased ADH= kidneys release less water = increased BP
Risk factors for Atherosclerosis?
smoking, hypertension, diabetes, increased levels of LDL – low density lipoprotein and decreased levels of HDL – high density lipoprotein,
What do aneurysms have the potential for?
Potential for aortic dissection, rupture, hemorrhage
Infarction and subsequent necrosis of a central organ are life threatening in?
Embolisms
Ischemia or infarction in tissue distal to obstruction – organ dysfunction and pain
Life threatening – coronary – cause MI
- cerebral artery – Stroke
What is Venous Stasis?
1/3 DVT risk factors
- Bed rest
- *Immobility
- Spinal cord injury
- Heart failure
What is Chronic venous insufficiency (CVI)?
Is inadequate Venus return over a long period of time
Main manifestations of PAD?
-Pain worse when elevating legs, improves with dangling
-Sores that do not heal
-Shiny, hairless skin
-Ulceration can occur from a slight injury and in most severe stages gangrene can occur
What are the two kinds of True aneurysms?
Saccular and Fusiform
Complicated hypertension as a hypertensive crisis
Hypertensive crisis – malignant hypertension – sustained over 180 (looking at it repeatedly)
Rapid progression of hypertension -
Increase arterial pressure = vascular fluid pushed into interstitial space – cerebral edema or encephalopathy – other systems involved – medical emergency
Where do pulmonary embolisms originate?
They originate on the venous side (mostly from DVT of the legs) of the systemic circulation or in the right heart
What is malignant hypertension?
It is a rapidly progressive hypertension in which diastolic pressure is usually greater than 140mm HG and is a hypertensive crisis /medical emergency
Causes of Atherosclerosis?
Consumption of high fat and cholesterol containing LDL foods
Hypertension, smoking and obesity (inhibits the oxidation of LDL
Diabetes, hyperlipidemia
Insulin resistance, infection and periodontal disease
What is a significant cause of venous thrombosis?
altered blood coagulation, stasis of blood, vessel wall injury
Patho process for DVT? what does it result in?
Accumulation of clotting factors and platelets – particularly close to valves lead to thrombus formation in a vein
Inflammation around thrombus – more platelets
After significant obstruction – increased pressure behind clot = edema in extremity
Most thrombi dissolve without treatment
What is Atherosclerosis?
It is a* form of arteriosclerosis* that is caused by the accumulation of lipid-laden macrophages within the arterial wall, which leads to the formation of a lesion called a PLAQUE
Manifestations of aneurysms?
Manifestations depend on location:
Can be asymptomatic until they rupture – then severe pain and hypotension
Thoracic – dysphagia, dyspnea – bulge affects surrounding tissue
Femoral aneurysm – if it affects circulation - Ischemia to lower limbs
Cerebral – circle of Willis – to be studied in neuro – increased ICP – signs of stroke – leaking cerebral aneurysm
What is an aneurism?
It is a localized dilation or outputting of a vessel wall or cardiac chamber
What is secondary hypertension? what does it frequently involve?
Occurs with another underlying disease – frequently involves kidneys (there is a cause)
Medications can cause hypertension, pregnant, tumour…
Fix the disease, BP will resolve
An underlying disease process or medication that rises peripheral vascular resistance or cardiac output can cause secondary hypertension
What happens if there is permanent occlusion of the peripheral writers in Buerger’s disease?
Permanent occlusion – collateral vessels develop but are inadequate – not quick enough, lower blood volume
What is Buerger’s disease?
-It is a peripheral vascular disease (peripheral partiers are occluded)
-It is an inflammatory disease of the peripheral arteries and is associated with smoking
Formation of thrombi in peripheral arteries – overtime thrombi organized and fibrotic (eventually become necrotic if not watching it)
How are embolisms introduced to the body?
Bolus of Air – IV lines, chest trauma
Amniotic fluid – intraabdominal pressure during delivery – amniotic fluid forced into blood stream
Fat – trauma of the long bones (car accident)
Bacteria – subacute bacterial endocarditis or abscess (cancer cells)
Foreign body – introduced through IV or arterial lines
What is Atherosclerosis Vs Arteriosclerosis
Arteriosclerosis – thickening and hardening of vessel/artery walls
Atherosclerosis – build up of plaques of lipid material on artery walls, clot off coronary arteries
