PERFUSION Flashcards
What is the definition of perfusion?
Perfusion refers to the flow of blood through arteries and capillaries, delivering nutrients and oxygen to cells and removing cellular waste products.
What can alteration in perfusion impair?
Alteration in perfusion may impair circulation of blood through the tissues.
What is ischemia?
Ischemia is a condition characterized by insufficient blood flow to tissues.
What is infarction?
Infarction refers to tissue death due to a lack of blood supply.
What does anoxia mean?
Anoxia is a condition of insufficient oxygen in the tissues.
What happens during systole in the cardiovascular system?
Systole is the contraction of ventricles, where the right ventricle sends blood to pulmonary circulation and the left ventricle sends blood into systemic circulation.
What is the average stroke volume?
The average stroke volume is 70 mL, ranging from 60-100 mL.
What is ejection fraction (EF)?
Ejection fraction is stroke volume divided by the volume in the ventricle at the end of diastole, representing the fraction of diastolic volume ejected during systole.
What is the normal range for ejection fraction?
Normal ejection fraction is 50-70%.
What is cardiac output (CO)?
Cardiac output is the amount of blood pumped by the ventricles in one minute.
What is the normal range for cardiac output?
Normal cardiac output is 4-8 L/min.
What factors affect cardiac output?
- Heart Rate (HR) * Stroke Volume (SV)
What is preload?
Preload is the volume of blood in the ventricles at the end of diastole.
How does dehydration affect stroke volume?
Dehydration decreases stroke volume.
What is contractility?
Contractility is the ability of myocardial fibers to shorten, resulting in contraction.
What is afterload?
Afterload is the peripheral resistance against which the left ventricle must pump.
What is the definition of blood pressure?
Blood pressure is the force exerted by blood against blood vessel walls.
What are the main factors influencing blood pressure?
- Cardiac Output (CO) * Systemic Vascular Resistance (SVR)
What is pulse pressure?
Pulse pressure is the difference between systolic blood pressure (SBP) and diastolic blood pressure (DBP).
What is the normal range for pulse pressure?
Normally, pulse pressure is about 1/3 of the SBP.
What is the mean arterial pressure (MAP)?
MAP is the average pressure within the arterial system that is felt by organs in the body.
What MAP is needed to perfuse vital organs?
A MAP of 60 mmHg is needed to perfuse vital organs.
Who are populations at greatest risk for impaired perfusion?
- Middle-aged and older adults * Men * African Americans
What are common age-related changes affecting the cardiovascular system?
- Increased collagen, decreased elastin * Decreased response to stress * Thickening of heart valves * Decrease in pacemaker cells
What does CPK stand for in cardiac biomarkers?
CPK stands for creatinine phosphokinase.
What is the significance of troponin in cardiac diagnostics?
Troponin is the biomarker of choice in the diagnosis of acutely impaired cardiac perfusion.
What is the normal range for creatinine?
Normal creatinine levels are 0.6-1.3 mg/dL.
What defines hypertension?
Hypertension is defined as persistent elevation of systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg.
What is isolated systolic hypertension (ISH)?
ISH is defined as SBP >140 mm Hg with DBP <90 mm Hg.
What are common risk factors for primary hypertension?
- Age * Alcohol * Tobacco use * Diabetes mellitus * Elevated serum lipids * Obesity * Family history
What is the pathophysiology of primary hypertension?
- Genetic links * Water and sodium retention * Stress and increased SNS activity * Endothelial cell dysfunction
What are clinical manifestations of hypertension?
Hypertension is often referred to as the ‘silent killer’ due to frequent asymptomatic presentation.
What are some complications of hypertension?
- Hypertensive heart disease * Stroke * Peripheral vascular disease * Nephrosclerosis * Retinal damage
What lifestyle modifications can help control blood pressure?
- Weight reduction * Dietary sodium reduction * DASH diet * Physical activity
What dietary changes can help reduce blood pressure?
DASH diet including:
* Fish
* Fruits & vegetables
* Fiber
* Water
* Whole grains
* Nuts
* Poultry
* Seeds
* Beans
BP decreases similarly to using antihypertensive medications.
What is the recommended daily sodium intake for healthy individuals?
2300 mg sodium/day
1500 mg if hypertensive, older, African American, diabetic, or with chronic kidney disease.
How much alcohol consumption is recommended for men and women?
Men: no more than 2 drinks/day
Women: no more than 1 drink/day
What is a first-line treatment for hypertension?
First Line Treatment includes:
* Diuretics
* ACE inhibitors
* ARBs
* Beta blockers
* Calcium channel blockers
What are diuretics used for?
Accelerate urine formation to remove sodium and water
Used in the treatment of hypertension, heart failure, and renal failure.
What are the types of diuretics?
Types of diuretics include:
* Loop diuretics
* Potassium-sparing diuretics
* Thiazide diuretics
What is the most commonly used diuretic for hypertension?
Thiazide diuretics such as Hydrochlorothiazide (HCTZ)
What adverse effect is commonly associated with thiazide diuretics?
Hypokalemia
What is the action of loop diuretics?
Inhibit chloride and sodium resorption in the ascending limb of the loop of Henle
Increases renal prostaglandins leading to blood vessel dilation.
What is the most commonly used loop diuretic?
Furosemide (Lasix)
What are potassium-sparing diuretics designed to do?
Interfere with sodium–potassium exchange and block aldosterone receptors
What are the adverse effects of Spironolactone?
Adverse effects include:
* Gynecomastia
* Amenorrhea
* Irregular menses
* Hyperkalemia
What is the mechanism of action of ACE inhibitors?
Blocks ACE, preventing conversion of angiotensin I to angiotensin II
What are some common ACE inhibitors?
Common ACE inhibitors include:
* Enalapril
* Lisinopril
* Ramipril
What are the indications for ACE inhibitors?
Indications include:
* Hypertension
* Heart failure
* Cardioprotection post-MI
* Renal protection in diabetes
What are the common adverse effects of ACE inhibitors?
Adverse effects include:
* Hyperkalemia
* Postural hypotension
* Dry cough
* Angioedema
What are Angiotensin II Receptor Blockers (ARBs) often referred to as?
Sartan sisters
What is the action of ARBs?
Block the binding of Angiotensin II to its receptors, preventing vasoconstriction and aldosterone secretion
What is the main action of beta blockers?
Reduce heart rate and decrease peripheral vascular resistance
What are some common beta blockers?
Common beta blockers include:
* Propranolol
* Metoprolol
* Atenolol
What are the nursing implications for patients on beta blockers?
Monitor pulse rates daily; report rates < 60 beats/min; avoid abrupt discontinuation
What is the primary use of Calcium Channel Blockers (CCBs)?
Treatment of hypertension and angina
What is a common side effect of centrally acting adrenergic agonists?
Drowsiness and dry mouth
What are vasodilators used for?
Treatment of hypertension
What is a hypertensive crisis defined as?
SBP >180 mmHg and/or DBP >110 mmHg
What is the classic symptom of Peripheral Arterial Disease (PAD)?
Intermittent claudication
What are the risk factors for developing PAD?
Risk factors include:
* Cigarette smoking
* Hyperlipidemia
* Hypertension
* Diabetes mellitus
* Chronic kidney disease
What is the ankle-brachial index (ABI) threshold for severe PAD?
< 0.40
What is the recommended exercise therapy for PAD?
Walking 30 to 45 minutes daily, 3-5 times a week
What are the goals of nutritional therapy for PAD?
Goals include:
* Maintain BMI < 25 kg/m2
* Waist circumference <40 inches for men and <35 inches for women
What is the process of opening an artery and removing plaque called?
Ectomy
What does patch graft angioplasty involve?
Opening artery, removing plaque and sewing patch to widen lumen
What is the goal of amputation in the context of limb preservation?
Preserve as much of limb as possible
What is a nursing diagnosis for Peripheral Arterial Disease related to tissue perfusion?
Ineffective tissue perfusion (peripheral)
Identify two nursing diagnoses for Peripheral Arterial Disease.
- Impaired skin integrity
- Chronic pain
What is a key aspect of nursing implementation for patients with Peripheral Arterial Disease?
Health Promotion
What dietary modifications should be made for at-risk patients?
- Reduce fat
- Reduce cholesterol intake
What should be regularly monitored after surgery for patients with Peripheral Arterial Disease?
- Skin color and temperature
- Capillary refill
- Presence of peripheral pulses distal to the operative site
- Sensation and movement of extremity
Name two potential complications to monitor for after surgery.
- Hematoma
- Thrombosis
What position should be avoided to prevent occlusion of bypass graft?
Knee-flexed positions except for exercise
What is the purpose of blood transfusion?
- Increase circulating blood volume after surgery, trauma, or hemorrhage
- Increase number of RBCs & hemoglobin levels in severe anemia
- Provide selected components as replacement therapy
True or False: Blood transfusions are common treatments that can be life-threatening.
True
What is essential to prevent transfusion reactions?
Proper identification of recipient and blood product
What is the ABO blood system based on?
Presence or absence of A and B red blood cell (RBC) antigens
What are the characteristics of a type A blood individual?
Has A antigens on RBCs and anti-B antibodies in plasma
What is a universal blood recipient?
People who have type AB blood
What defines a type O individual in terms of blood antigens?
Has neither A nor B antigens on RBCs but has both anti-A and anti-B antibodies in plasma
What is autologous transfusion?
The collection and reinfusion of a patient’s own blood
When is blood typically collected for autologous transfusion?
Before or during surgery & transfused after surgery
Why is autologous transfusion considered safer?
Safer than transfusion of another person’s blood
