15 Alterations in Blood Flow Flashcards
5 types of obstruction that cause altered flow
1 arteriosclerosis/atherosclerosis 2 inflammation 3 vasospasm 4 thrombi/emboli 5 acute occlusion
2 types of mechanical alterations that cause altered flow
1 arteriovenous fistulas (arteriovenous malformation)
2 aneurysm
effects of reduction in flow
*impairs ability to transport gases + nutrients to body tissues 1 hypoxia 2 ischemia 3 venous engorgement 4 venous obstruction
Obstructions in BLOOD VESSELS
effects
- reduced flow beyond the obstruction
- increased pressure before the obstruction
Obstructions in BLOOD VESSELS
arterial vs venous system manifestation
A: distal ischemia
V: edema
Thrombus
stationary blood clot formed w/in a vessel or chamber of heart
Thrombosis
treatment
1 anticoagulant therapy
2 thrombolytic drugs
3 surgery to remove thrombus
anticoagulant therapy
- used to prevent clot enlargement
- blood thinner
Embolus aka Thromboembolus
- traveling clot
- -material that forms a clot w/in the bloodstream
embolus leaving L ventricle
ISCHEMIC STROKE
- differ depending on brain area affected
- loss of cogntv functn, motor changes, diff levels of sensory loss
embolus leaving R ventricle
PULMONARY EMBOLUS
- vague, nonspecific
- most common: sudden onset of shortness of breath, inc resp rate, chest pain, sudden death
Other causes of Emboli
1 fat 2 malignant neoplasm/tumor 3 collection of bacteria/infectious exudate 4 air 5 amniotic fluid
Embolus
treatment
1 Embolectomy
2 filter in inferior vena cava
Artetiosclerosis/Atherosclerosis
hardening + narrowing in medium + large sized arteries
lipoprotein
soluble protein that combines/transports fat in plasma
PDGF
platelet-derived growth factor
- released by aggregation of platelets
- stimulated the growth of smooth muscles
Foam Cells
lipid-filled macrophages
- macrophage engulf lipids turning into FOAM CELLS
- -release inflammatory mediators (attract more leukocytes) + growth factors (stim smooth muscle proliferation)
Arteriosclerosis/Atherosclerosis
Process
1 initiated by ENDOTHELIAL SURFACE DAMAGE to arterial intima
-initiates inflammatory respns + inc vessel wall permeability
2 LOW-DENSITY LIPOPROTEINS breach intimal layer
–leukocytes + endothelial cells oxidize lipids
3 oxidized lipids are damaging to endothelial + smooth muscle cells
–stim recruit of macrophage
4 platelet aggregate + release PDGF
–stim growth of smooth muscles
5 TUNICA MEDIA SMOOTH MUSCLE CELLS move to intima where they proliferate + HARDEN
6 MACROPHAGE engulf lipids; FOAM CELLS release inflammatory mediators + GF
–attract more leukocytes + stim smooth muscle growth
7 excess lipid + debris accumulate w/in vessel wall + coalesce into lipid core (NARROWING)
what causes the “hardening” + “narrowing” in Arteriosclerosis/Atherosclerosis
HARD: when tunica media smooth muscles move inwards to intima where they proliferate and harden
NARROW: excess lipid + debris accumulate w/in vessel wall + coalesce into lipid core
Arteriosclerosis/Atherosclerosis can lead to…
1 hypertension 2 cardiac CAD + renal disease 3 peripheral arterial disease 4 stroke 5 myocardial infarction
Atherosclerosis Plaque
- causes narrowing
- slowly enlarge> orifice or artery decreases +perfusion diminished
- primarily composed of smooth muscle cells, epithelium, blood clot, lipoprotein, + inflammatory debris
perfusion
passage of blood/fluid through vessels
NONmodifiable risk factors of Arteriosclerosis/Atherosclerosis
- age
- gender
- ethnicity
- fam history of CAD
Modifiable risk factors of Arteriosclerosis/Atherosclerosis
1 Phys activity
2 Stress + Mental Health
3 Tobacco
4 Hypertension
5 Cholesterol, Lipoprotein, Triglycerides
6 Glucose Intolerance/Metabolic Syndrome, + Diabetes
7 Obesity
physical activity as treatment/prevention for Arteriosclerosis/Atherosclerosis
INC: HDL lvl, collateral circ, vessel size
DEC: tot cholesterol lvl, glucose intolerance, body weight, + BP
stress + mental health for Arteriosclerosis/Atherosclerosis
stress + depression increase risk
tobacco on Arteriosclerosis/Atherosclerosis
-injures epithelium
INC: LDL, cholesterol, triglycerides, platelet aggregation, BP + heart rate, risk of coronary heart disease [CHD]
DEC: HDL
hypertension on Arteriosclerosis/Atherosclerosis
hypertension increases risk
Cholesterol on Arteriosclerosis/Atherosclerosis
excess cholesterol acts as irritant causing PLAQUE formation
Lipoproteins on Arteriosclerosis/Atherosclerosis
high levels of LDL promotes atherosclerosis
high levels of HDL inhibits
Glucose Intolerance/Metabolic Syndrome, + Diabetes on Arteriosclerosis/Atherosclerosis
increases risk of Arteriosclerosis/Atherosclerosis
Obesity on Arteriosclerosis/Atherosclerosis
ACCELERATES atherosclerotic process
Raynaud Syndrome
extreme vasoconstriction producing cessation of flow to fingers + toes
-color changes like cyanosis or red due to hyperemia, pain, numbness, cold trigger attacks
cyanosis
white/blue discoloration of skin fr poor circulation or lack of oxygen
hyperemia
excess of blood in vessels supplying an organ or part of body
-red
Aneurysm
localized arterial dilation, bulge outward
- frequently found in cerebral circulation + thoracic + abdominal aorta
- classified as true or false aneurysms
true aneurysms
SACCULAR: one-sided balloon
FUSIFORM: both sides balloon out
BERRY: balloon has stem/neck
Aneurysm
clinical manifestations
AORTIC: sudden severe tearing pain, radiates into back/abdomen, shock
CEREBRAL: increasing intracranial pressure, hemorrhaging stroke
Aneurysm
tests
AORTIC: CT, MRI, cerebral angiography
CEREBRAL: CT, TEE
Acute Arterial Occlusion
absence of arterial circulation-emergency
-may result fr thrombi/emboli or mechanical compressin
Acute Arterial Occlusion
classic signs + symptoms
1 pallor 2 paresthesia 3 paralysis 4 pain 5 polar 6 pulseless
Acute Arterial Occlusion
treatment
medical + surgical 1 loosen tight dressing 2 cut cast 3 anticoagulant therapy 4 thrombolytic therapy 5 bypass surgery 6 embolectomy 7 amputation
4 alterations to ARTERIAL flow
1 Arteriosclerosis/Atherosclerosis (obstruction) 2 Raynaud Syndrome 3 Aneurysm (mechanical alteration) 4 Acute Arterial Occlusion (obstruction)
3 Alterations in VENOUS Flow
1 Varicose Veins
2 Chronic Venous Insufficiency
3 Deep Vein Thrombosis
alterations to venous flow are usually accompanied by…
edema
venous stasis ulcers
pain
life-threatening type of alteration to venous blood flow
Deep vein thrombosis
valvular incompetence
cause + manifestations
- overstretching valves owing to excessive venous pressures resulting in backflow of blood
- obesity, pregnancy, RT heart failure, prolonged standing
-results in Venous insufficiency + varicose veins
valvular incompetence
treatment
- smoking cessation
- reg walk/exercise
- drugs that interfere w platelet aggregation
Varicose Veins
impaired venous returns results in superficial darkened, raised, tortuous veins
most common vein affected by varicose
Greater Saphenous Vein
Varicose Veins
treatment
- increase venous flow + reduce venous pressure
- sclerotherapy + surgical interventions for severe cases
- elevate legs, avoid standing, elastic stockings
- vein stripping + vein ligation
Chronic Venous Insufficiency
- results when valvular incompetence involves DEEP veins
- venous stasis ulcers are typically present, skin turns brown
Chronic Venous Insufficiency
evaluation + treatment
- ultrasound is best method for evaluation
treatment: compression therapy + infection control
Deep Vein Thrombosis
- due to thrombus in a deep vein in lower extremity
- may be asymptomatic
Deep Vein Thrombosis
risk factor + treatment
- previous DVT is a risk factor for further hypercoagulation
- treated aggressively w Anticoagulation therapy
thrombus vs emboli
thrombus is a blood clot
emboli is a traveling clot