101 terms

Alterations in oxygenation: Vascular disruptions

Overview of alterations in the vascular system
- Disorders of arterial circulation
- Disorders of venous circulation
- Disorders of blood flow due to extravascular forces.
Disorders of arterial circulation
H. A. V. A
- Decreased blood flow to tissues, impaired delivery of oxygen and nutrients
- Hyperlipidemia
- Atherosclerosis
- Vasculitis
- Arterial disease of the extremities.
Disorders of arterial circulation: Hyperlipidemia
- abnormally elevated levels of any or all lipids and/or lipoproteins in the blood.
- Triglycerides (the main storage from of lipids)
- Phospholipids
- Cholesterol
Disorders of arterial circulation: Atherosclerosis: word origin
- from Greek words
- Athero: fatty mush or paste
- Skleros: hard
Disorders of arterial circulation: Vasculitis
- Inflammatory injury and necrosis of blood vessel wall
can be caused by
- Direct injury to vessel
- infectious agents
- Immune process
- secondary to other diseases
Disorders of arterial circulation: Arterial disease of the extremities: Type
- Atherosclerotic occlusive disease
- Aortic aneurysms
Arterial disease of the extremities Atherosclerotic occlusive disease
- Superficial femoral and popliteal arteries most affected
- most common in men in 60s and 70s
Arterial disease of the extremities Aortic Aneurysms
- Localized dilation or outpouching of arterial vessel wall
- involves damaged media layer of vessel
2 most common causes
- atherosclerosis
- degeneration of vessel media
Disorders of the venous circulation
Vv. Vsu. Vt. E
- Varicose veins
- Venous stasis ulcers
- Venous thrombosis
- Embolus
Disorders of the venous circulation: Varicose veins
- Dilated, tortuous veins of lower extremities
common causes
- age (over 50)
- Obese
- Women
- Heredity
Disorders of the venous circulation: Venous stasis Ulcers
- Usually above medial malleolus
- poorly and slowly healing ulcer
Disorders of the venous circulation: Venous thrombosis (thrombophelebitis)
- Presence of thrombus (blood clot) in vein and inflammatory response in vessel wall
- Virchow's triade
- Can occlude artery causing ischemia
- Can be dislodged, becoming thromboembolus that travels through vascular system until occluding flow in a small vascular bed
Disorders of the venous circulation: Venous thrombosis (thrombophelebitis): virchow's triade
- The three main factors in the etiology of Venous thrombosis
- stasis of blood (impaired venous blood flow)
- Increased blood coagulability (Hypercoagulability)
- Vessel wall injury
Disorders of the venous circulation: Embolus
- Bolus of matter circulating in the bloodstream
- usually a complication of heart disease
may consist of:
- dislodged thrombus
- fat
- air bubble
- amniotic fluid
- foreign body
Disorders of blood flow due to extravascular forces
Cs. Pu. Ipr.
- Compartment syndrome
- Pressure ulcers
- Increase in peripheral resistance
Disorders of blood flow due to extravascular forces:
Compartment syndrome
- Increased pressure in limited anatomic space
- impairs circulation and produces ischemic tissue injury
Disorders of blood flow due to extravascular forces:
Pressure ulcers
- Ischemic lesions of skin and underlying structures
- caused by external pressure that impairs flow of blood and lymph
Disorders of blood flow due to extravascular forces:
Increase in peripheral resistance
- The heart has to pump harder leading to hypertrophy
- leads to decreased blood supply to an area.
Conditions associated with Increased Peripheral Resistance
- Hypertension
- Presence of renal or endocrine problems
Conditions associated with Increased PR:
- Elevation of systemic blood pressure
Conditions associated with Increased PR:
Presence of renal or endocrine problems
- Hormones control vasodilation and constriction
- Kidneys control sodium excretion and extracellular fluid volume
Atherosclerosis: Definition
- Formation of fibrofatty lesions in large and medium vessels
- Marked by cholesterol-lipid-calcium deposits
- arteries become narrowed and reduce the flow of blood through the arteries.
- Leading cause of coronary artery and cerebral vascular disease.
Risk factors associated with development of atherosclerosis that cannot be changed
H. G. A. E
- Heredity
- Gender
- Age
- Ethnicity
Risk factors associated with development of atherosclerosis that can be changed
Cs. Hbp. Esl. Pi. O
- cigarette smoke
- High blood pressure
- Elevated serum levels
- Physical inactivity
- Obesity
Atherosclerosis contributing factors
D. S. Crp. H. L
- Diabetes
- Stressful lifestyle
- C-reactive protein (Protein produced by the liver)
- Homocysteine (Amino acid produced in protein catabolism)
- Lipoprotein
Atherosclerosis pathogenesis
Fs. Fap. Cl
- Fatty streaks
- Fibrous atheromatous plaque
- Complicated lesions
Atherosclerosis pathogenesis:
Fatty streaks
- Flat, yellow, lipid-filled smooth muscle cells
- enlarges by becoming thicker and slightly elevated.
- Macrophages and smooth muscle cells become distended and form foam cells
- immunologic and inflammatory changes result in progressive damage to the wall
- can be reversible
Atherosclerosis pathogenesis:
Fibrous atheromatous plaque
- Lesions of advancing atherosclerosis
- arterial wall changes initiated by chronic endothelial injury of many factors
- lesion is gray/white, elevated and protrudes into lumen of artery
- after endothelial injury, lipoproteins transport cholesterol and other lipids into arterial intima (innermost layer of the artery)
Atherosclerosis pathogenesis:
Complicated lesion
- Most dangerous
- Plaque consists of lipids within area of dead tissue
- Rigidity and hardening
- may totally or partially occlude artery
atherosclerosis: Theories of the mechanisms of development
- endothelial cell injury
- Migration of inflammatory cells
- smooth muscle cell proliferation and lipid deposition
- gradual development of the atheromatous plaque with a lipid core.
Atherosclerosis: Clinical manifestations
- Depends on vessel involved and extent of vessel obstruction
- Ischemia
- Infarction: tissue that undergoes necrosis following cessation of blood supply
- Necrosis: death of an area due to insufficient blood supply
Atherosclerosis: management
D. Dt. Sc. E. Dt
- Diagnostic
- Diet Therapy
- Smoking cessation
- Exercise
- Drug Therapy
Atherosclerosis: management:
Diagnostic: Serum lipid tests
- Cholesterol is manufactured by liver but also present in many foods
- used in synthesis of steroid hormones and to form bile salts
- Transported by combining with proteins called lipoproteins
Hd. Ld. Vld
- High-density Lipoproteins
- Low-density Lipoproteins
- Very-low-density Lipoproteins
High-density Lipoproteins (HDL)
- Carries fat away from cells to be degraded in the liver
- protects against atherosclerosis
- "good" cholesterol
Low-density Lipoproteins (LDL)
- Carries fat to cells of body
- Has an affinity for arterial walls
- "bad" cholesterol
Very-Low-density Lipoproteins (VLDL)
- Contains mostly triglycerides
- Direct correlation with heart disease is uncertain
Serum Lipid tests types
Tc. Cf. T. A. A
- Total cholesterol
- Cholesterol fractionation
- Apolipoprotein A-1
- Apolipoprotein B
Serum Lipid tests: Total Cholesterol
- Measures serum cholesterol
- normal range is 140-200mg/dl
- Considered a risk if more then 200
Serum Lipid tests:
Cholesterol Fractionation
- Measures types of cholesterol
- HDL desirable above 60mg/dl
- LDL desirable if less then 130mg
Types of fatty acids
- Saturated fats: the amount in diet is most significant factor in raising blood cholesterol
Unsaturated fats
- Monounsaturated fats lower LDL
- Polyunsaturated fats lower both LDL and HDL
Serum Lipid tests: Triglycerides
- Provides an early ID of hyperlipidemia and risk of Coronary artery disease.
Serum Lipid tests: Apolipoprotein A-1
- Primarily found in HDL
- Assesses cholesterol clearing capacity
Serum Lipid tests: Apolipoprotein B
- Assesses cholesterol depositing capacity of blood
Atherosclerosis management:
Diet Therapy
- Decrease saturated fat (8-10% of calories) and cholesterol.
- Less than 30% of total calories from fat
- visible fat - 1 tsp per meal
- only unsaturated vegetable oils
- lean meats, skim milk, no more then 3 egg yolks/week
- avoid high fat food.
Atherosclerosis management:
Smoking cessation
- Cigarette smokers have 70% greater CAD death rate then nonsmokers
Atherosclerosis management:
- Tones muscles, stimulates circulation, helps prevent obesity, promotes general feeling of well-being
- Aerobic activities especially valuable
- may increase development of collateral vessels
- may reduce amount of circulating fat and increase HDL
Atherosclerosis management:
Drug therapy
Bas. N. Fad. Hcri. Cai
- Used only if serum lipoproteins are not reduced by reasonable trial of dietary modification.
- Bile acid sequestrants
- Niacin
- Fibric acid derivatives
- HMG CoA reductase inhibitors (statins)
- Cholesterol Absorption inhibitor
Atherosclerosis management:
Drug therapy: Bile Acid Sequestrants
- Binds with bile acids in intestines
- removes LDL
- Questran and Colestid
Atherosclerosis management:
Drug therapy: Niacin
- Inhibits synthesis of VLDL and LDL.
- Increases HDL
- Nicobid, Niarcor
Atherosclerosis management:
Drug therapy: Fibric acid derivatives
- Decreases hepatic synthesis of VLDL
- Increases HDL
Atherosclerosis management:
Drug therapy: HMG CoA reductase inhibitors (statins)
- Blocks synthesis of cholesterol
- Decreases LDL
- Increases HDL
- Zocor, lipitor
Atherosclerosis management:
Drug therapy: Cholesterol Absorption Inhibitor
- Inhibits intestinal absorption of cholesterol
- Zetia
Peripheral Arterial Disease:
- Interruption of blood supply
- Slow and painful healing process
- may be compounded by other medical problems
- May appear minor but disabling when healing
- recurrence is frequent
Peripheral Arterial Disease:
Risk Factors
- Same risk factors as atherosclerosis
- Controllable: tobacco use, HTN, Obesity, Sedentary lifestyle, stress, diabetes
- uncontrollable: Age, genetics, gender, ethnicity
Peripheral Arterial Disease:
Clinical manifestations
- Intermittent claudication (leg pain): severe cramp-like pain in affected extremity(ies), usually associated with activity
- Skin may become pale, mottled and shiny in appearance
- temperature of skin is cool to cold
- Diminished to absent pulses in extremity
- Pain, ischemia, impaired function, also may be infarction and tissue necrosis
Peripheral Arterial Disease:
- Decreased blood supply
- Increased healing time
- Infection
- gangrene
Peripheral Arterial Disease:
Dt. Dt. Ctm. I/sm
- Diagnostic tests
- Drug therapy
- Conservative therapeutic management
- Invasive/surgical management
Peripheral Arterial Disease:
Management: Diagnostic tests
Dus. Abi. A
- Doppler ultrasound studies
- Ankle-brachial index
- Angiography
Doppler ultrasound studies
- Noninvasive
- evaluates blood flow in major veins and arteries
Ankle-brachial index
- used to monitor patency of bypass grafts
- x-ray with contrast dye
- can visualize blood vessels
Peripheral Arterial Disease:
Management: Drug therapy
- Analgesics- variety of drugs help relieve pain
- Antiplatelet agents: Pentoxifylline, Pletal
Antiplatlet agents: Pentoxifylline (trental)
- Improves capillary blood flow by increasing RBC flexibility and lowering blood viscosity
Antiplatlet agents: Pletal
- Inhibits platelet aggregation
- Increases vasodilation
- inhibits smooth muscle cell proliferation.
Peripheral Arterial Disease:
Management: Conservative therapeutic management
- Risk factor modification
- positioning (use gravity to your advantage)
- walking
- foot care
- nutritional therapy
Peripheral Arterial Disease:
Management: Invasive/surgical
Ptba. E. Abg. A
- Percutaneous transluminal balloon angioplasty
- Endarterectomy
- Aortofemoral bypass graft
- Amputation
Peripheral Arterial Disease:
Management: Invasive/surgical
Percutaneous transluminal balloon angioplasty
- Tries to improve blood flow by cracking plaque
- 50% chance of re-stenosis in 1 year
Peripheral Arterial Disease:
Management: Invasive/surgical
- Surgical removal of lining of the artery
Peripheral Arterial Disease:
Aortofemoral bypass graft
- replace diseased parts of arteries and veins
Peripheral Arterial Disease:
- removal of a limb or part
Essential (primary) hypertension
- Consistent elevation of systemic arterial blood pressure.
- Systolic over 140 and diastolic over 90
Essential (primary) hypertension: risk factors
- Family history
- Advancing age
- Race
- Insulin resistant and resultant hyperinsulinemia
Essential (primary) hypertension: lifestyle factors
- Contribute by interacting with risk factors
- High salt intake
- excessive calorie intake and obesity
- physical inactivity
- excessive alcohol consumption
- low intake of K
- Stress, smoking, diet high in saturated fats.
Essential (primary) hypertension: Possible pathogenesis
- several factors, hemodynamic, neural, humoral, and renal mechanisms, are thought to interact to produce long term elevations in BP.
- sympathetic nervous system activity
- kidney function (water and sodium retention)
- electrolyte composition
- cell membrane transport mechanisms
- Humoral influences
Factors influencing BP
Cardiac output
- Cardiac
- Renal fluid volume control
Systemic vascular resistance
- Sympathetic Nervous system
- Local regulation
- Humoral
Factors influencing BP: Cardiac
- Heart rate
- Inotropic state (muscle contraction strength)
- Neural
- humoral
Factors influencing BP: Renal Fluid Volume Control
- Renin-angiotensin
- Aldsterone
- Atrial natriuretic factor
Factors influencing BP: Sympathetic Nervous System
- Alpha-adrenergic receptors (vasoconstriction)
- Beta-adrenergic receptors (vasodilation)
Factors influencing BP: Local regulation
- Vasodilators: prostaglandins, EDRF
- vasoconstrictors: endothelin
Factors influencing BP: Humoral
- vasoconrictors: angiotensin, catecholamines
Essential (primary) hypertension: Clinical manifestations
- early stages often have none other than elevated BP
- Often called a "silent killer"
- symptoms secondary to effects on blood vessels or increased work of heart: fatigue, reduced activity tolerance, dizziness, palpitations, angina and dyspnea
Essential (primary) hypertension: Complications
- Cardiac complications
- CNS complications: higher risk of stroke
- renal complications: leading cause of end stage renal disease
- eye complications
Essential (primary) hypertension: Management: diagnostic studies
B. C. C. E
- BP Check
- Cholesterol levels
- Chest x-ray
Essential (primary) hypertension: Management: Pharmacologic therapy
D. A
- diuretics
- Antihypertensive medications
Essential (primary) hypertension: Management: Pharmacologic therapy:
- Enhance selective excretion of various electrolytes and water by affecting renal mechanisms for tubular secretion and reabsorption
- thiazides
- loop diuretics
- Potassium sparing diuretics
Essential (primary) hypertension: Management: Pharmacologic therapy:
Diuretics: Nursing interventions
Afs. Me. Mbp. Am. T
- Assess fluid status
- Monitor electrolytes
- Monitor BP and pulse
- Give in AM
- teach
Essential (primary) hypertension: Management: Pharmacologic therapy:
Diuretics: Thiazides
- Action increases sodium and water excretion by inhibiting sodium and chloride reabsorption in distal tubule
- hydrochlorathiazaide
Essential (primary) hypertension: Management: Pharmacologic therapy:
Diuretics: Loop diuretics
- inhibits sodium and chloride reabsorption at proximal and distal tubules and ascending loop of henle.
- Lasix
Essential (primary) hypertension: Management: Pharmacologic therapy:
Diuretics: Potassium sparing diuretics
- Causes excretion of sodium and calcium while conserving potassium and hydrogen ions
- Aldactone
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication
- treatment of Hypertension
- Used to lower Bp to normal levels
- Classified into groups according to site of action
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication: Nursing intervention
- Monitor BP
- Monitor I & O
- Monitor Weight
- Teaching
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication: types
Baba. Ccb. Caa. ai. aara. dasmv
- Beta-adrenergic blocking agents
- calcium channel blockers
- Central alpha agonists
- ACE inhibitors
- Alpha-adrenergic receptor antagonists
- Direct acting smooth muscle vasodilators
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication:
Beta-adrenergic blocking agents
- Reduces BP by antagonizing beta-adrenergic effects.
- Decrease Cardiac output and reduces sympathetic vasoconstrictor tone.
- decreases renin secretion by kidney
- Ie Inderal (propanolol)
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication:
Calcium channel blockers
- Inhibits transport of calcium into myocardial and vascular smooth muscle cells.
- results in inhibition of excitation-contraction coupling and subsequent contraction
- calan (verapamil)
- Procardia (nifedipine)
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication:
ACE (angiotension converting enzyme) inhibitors
- Prevents production of angiotension II by blocking its conversion to the active form
- results in systemic vasodilation
- vasotec (enalapril)
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication:
Central alpha agonists
- reduces sympathetic outflow from the CNS.
- Reduces peripheral sympathetic tone, producing vasodilation
- catapres (clonidine)
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication:
Alpha-adrenergic receptor antagonists
- Blocks alpha adrenergic receptors
- Results in peripheral vascular dilation
- Cardura (doxazosin)
Essential (primary) hypertension: Management: Pharmacologic therapy:
Antihypertensive medication:
Direct acting smooth muscle vasodilators
- Produces relaxation of vascular smooth muscles
- works best in combo with other HTN drugs
- Apresoline (hydralazine)
Essential (primary) hypertension: Management: Supportive treatments
- Dietary management (restriction to sodium, DASH diet)
- Weight control
- Exercise
- stress reduction
- Monitoring of BP
Essential (primary) hypertension: Management: Nursing Management
- Primary prevention
- Interventions associated with oxygenation need area
- Patient teaching.