Hemodynamics - EXAM 4

Question 1

What is the pathway of blood flow through the heart?

Answer 1

1. Inferior Vena Cava, Superior Vena go into the
2. Right atrium to the
3. Tricuspid Valve to the
4. Right Ventricle out the
5. Pulmonary semilunar valve into the
6. Pulmonary arteries to the
7. Lungs and then out of the
8. Pulmonary veins into the
9. Left atrium and through the
10. Mitral (bicuspid valve) into the
11. Left ventricle and then through the
12. Aortic valve into the
13. Aorta and then through the
14. Arteries and then the
15. Capillaries and meets up with the
16. Veins and all venous blood dumps into the
17. Inferior vena cava, superior vena cava

Question 2

What is blood pressure?

Answer 2

Pressure in the systemic arteries which is created by the ejection of blood from the left ventricle.

Question 3

What factors affect BP?

Answer 3

Cardiac output and systemic vascular resistance

Question 4

What is the Mean Arterial Pressure (MAP)?

Answer 4

Reflects the average or mean arterial pressure in the blood perfusing the organs. Changes in MAP are related to the dynamic relationship between cardiac output and systemic vascular resistance

Question 5

What does a low MAP indicate?

Answer 5

Decreased blood flow through the organs

Question 6

What does a high MAP indicate?

Answer 6

Increased cardaic workload

Question 7

What is the MAP needed to adequately perfuse and sustain vital organs of an average person?

Answer 7

60 mm Hg

roughly equal to a systolic blood pressure of 90 mm Hg

Question 8

What is starling’s law?

Answer 8

The greater the stretch of the ventricular muscle fiber, the greater the contraction, to a point.

Question 9

What is preload?

Answer 9

Preload occurs during diastole. The term refers to the volume of blood filling the ventricles prior to the beginning of systole. Preload is regulated by the variability in intravascular volume and the volume of blood returning to the ventricle.

WRONG. THIS IS WRONG

Question 10

What is afterload?

Answer 10

Afterload describes the resistance that the heart has to overcome, during every beat, to send blood forward into the aorta. These resistive forces include vasoactivity (blood vessel diameter and rigidity) and blood viscosity

WRONGGGGGGGGGg. This is WRONG. THESE TEACHERS ARE SO STUPID

Question 11

What is contractility?

Answer 11

Describes the strength of cardiac muscle contraction

Question 12

What is cardiac output?

Answer 12

The volume of blood pumped by the heart in one minute

HR X SV = CO

Question 13

What is stroke volume (SV)?

Answer 13

The amount of blood pumped by the heart per cardiac cycle. It is measured in mL/beat.

Question 14

What are positive Inotropes?

Answer 14

Any medication or circumstances that increases the force of cardiac contraction

Question 15

What are negative Inotropes

Answer 15

Any medication or cicumstances that decrease the force of cardiac contraction

Question 16

What is hemodynamic monitoring?

Answer 16

The measurment of pressure, flow, and oxygenation within the cardiovascular system. Values commonly obtained VIA an invasive catheter include central venous pressure, pulmonary artery pressure, pulmonary atery wedge pressure, cardiac output, and stroke volume.

Question 17

What is pulmonary vascular resistance (PVR)?

Answer 17

The measure of resistance of the pulmonary vascular bed to blood flow

Question 18

What is systemic vascular resistance?

Answer 18

The measurement of resistance of the systemic vascular bed to blood flow

Question 19

What is left ventricular ejection fraction?

Answer 19

Also referred to as ejection fraction. This is the percent of blood ejected from the left ventricle during one cardiac cycle. The average EF is 55-65%.

Question 20

What is central venous pressure (CVP)?

Answer 20

CVP readings are used to assess right ventricular function and general fluid status using an invasive hemodynamic catheter

Question 21

What is pulmonary artery pressure (PA pressure)?

Answer 21

Blood pressure in the pulmonary artery measured by invasive hemodynamic catheter.

Question 22

What is pulmonary wedge pressure (PAWP)?

Answer 22

PAWP pressures are used to assess the preload of the left ventricle. This is measured through the invasive hemodynamic catheter.

Question 23

Cardiac Output, Decreased

Answer 23

Definition: Inadequate volume of blood pumped by the heart/minute to meet metabolic demands of the body

Defining characteristics:

• Altered HR/rhythm, EKG changes
• Altered preload: edema, decreased CVP, fatigue, JVD, heart murmurs, weight gain
• Altered afterload: clammy skin, dyspnea, decreased peripheral pulses, increased PVR, oliguria, prolonged CRT, skin color changes
• Altered contractility: crackles, cough, decreased ejection fraction, orthopena, PND
• Behavioral/Emotional: anxiety, restlessness

Outcomes:

1. Pt. will demonstrate adequate CO as evidenced by BP, HR and rhythm within normal parameters for patient
2. Strong peripheral pulses and an ability to tolerate activity without symptoms of dyspnea, syncope, or chest pain

Nursing Interventions:

1. Monitor:
   
   1. S/sx of heart failure and decreased cardiac output
   2. Lung sounds, weight, dyspnea, orthopnea, PND, c/o fatigue or weakness
   3. Chest pain/discomfort, note location, radiationm, severity, quality, duration, and associated symptoms such as nausea, indigestion, and diaphoresis, note precipitating and alleviating factors
   4. I/O with hourly urine output
   5. Diagnostic imaging studies such as echo with particular attention to ejection fraction. EF less than 40% indicating heart failure
   6. Lab values, especially ABGs, electrolytes and B-type natriuretic peptide
   7. Bowel function, provide stool softeners and caution patient not to strain (avoid valsalva)
   8. Administer O2 per order to maintain satisfactory SpO2
   9. Check pulse, BP before and after administering ACE- I, digoxin, CCB and beta blockers

Question 24

What is the catheter called that is used in hemodynamic monitoring?

Answer 24

It is a special central venous catheter called the pulmonary artery catheter.

Question 25

Where is the pulmonary artery catheter inserted?

Answer 25

Through a central vein and is advanced until the tip of the catheter rests within a small branch of the pulmonary artery

Question 26

What is the purpose of inserting a pulmonary artery catheter?

Answer 26

The data obtained from the catheter provides measurable/numeric information about the overall functioning of the heart. This data enables the RN to continually assess the patient's response to actual or potential cardiac problems and adject the associated nursing care appropriately.

Question 27

What does the stupid student think preload is?

Answer 27

Preload is the volume of blood in the ventricle prior to contraction. Preload is related to the length and stretch of the myocardial fibers at the end of diastole. If you recall starling's law, the more a heart fiber is stretched during diastole, the greater the contraction of the muscle will be. This stretch is accomplished through filling of the ventricle with the blood. This is significant because the heart is a dynamic pump which must alter its output with the amount of blood it recieves. It is a necessary property of cardiac muscle that the force develope dudring systole is matche dto the volume of blood received during diastole. Proload then, is directly related to volume of vlood that the ventricle receives during diastole. Preload is mainly dependent on the return of venous blood from the body for the right ventricle and from the pulmonary system for the left ventricle. Venous return is influenced by changes in position, intra-thoracic pressure, blood volume, and the balance of constriction and dilation (tone) in the venous system. As preload is increased, the heart responds with a stronger contraction. This is seen with increase in both the stroke volume and cardiac output values. Increase in preload and the heart response require increase in both the energy and oxygen consumption of the heart's tissue (myocardial oxygen demand). Preload in the right ventricle is measured directly by the central venous pressure using an invasive catheter. Left ventricular preload can be measured indirectly through the use of a pulmonary artery catheter. The pulmonary wedge pressure is a reflection of left atrial pressure. \*\*some of this is correct, but mostly they are confused.

Question 28

What are the preload parameters?

Answer 28

Central Venous Pressure (CVP): Reflects fluid volume on the venous side of the vascular system Pulmonary Artery Wedge Pressure (PAWP): Fluid volume on the arterial side of the vascular system

Question 29

What are the factors that increase preload?

Answer 29

1. Increase in fluid intake 2. Vasoconstriction 3. Use of anti-emobolic stockings 4. Trendelenburg position or elevation of legs

Question 30

What are the factors that decrease preload?

Answer 30

1. Use of diuretics 2. Decrease in fluid intake 3. Use of vasodilators (such as nitrates and morphine)

Question 31

What data should be included in the assessment of preload status in patients with cardiac issues at the bedside without invasive hemodynamic monitoring?

Answer 31

1. Daily weight 2. Monitor 24 hour I&O, including IV fluids 3. Monitor edema 4. Assess for JVD, heart gallop (S3 or S4), and crackles 5. Assess skin turgor and moisture of mucuous membranes 6. Assess BP and pulse 7. Assess for thirst 8. Invasive pressure monitoring (R atrial pressure or central venous pressure) 9. Medication history (diuretics)

Question 32

If a patient demonstrated an increased in their CVP parameter, what would this represent as to preload?

Answer 32

Increase in CVP means increase in preload

Question 33

What do your stupid teachers think preload is?

Answer 33

Afterload is the resistance which the ventricles must pump blood out against. Afterload is determined by two conditions: blood pressure and the diameter of the blood vessels. If blood pressure increases or vessels are constricted, afterload is increased. The resistance of systemic BP to the left ventricle is the systemic vascular resistance (SVR). The resistance of pulmonary BP to the right ventricle is the pulmonary vascular resistance (PVR). kdshfkfhsdkjhfksjdhfk dumb

Question 34

What are the afterload parameters?

Answer 34

Pulmonary Vascular Resistance: reflects pressure in the pulmonary vascular bed Systemic Vascular Resistance: reflects pressure in the systemic arterial system (think vasomotor tone)

Question 35

What are some factors that increase afterload?

Answer 35

1. Left sided heart failure 2. Pulmonary diseases (COPD, etc) 3. Pulmonary or Systemic hypertension 4. Valvular stenosis (valves fail, blood leaks backward) 5. Vasoconstriction (from intrinsic factors such as hypothermia, or extrinsic factors such as medications)

Question 36

What are some factors that decrease afterload?

Answer 36

1. Vasodilation (from intrinsic factors such as sepsis/shock or extrinsic factors such as medications) 2. Hyperthermia (hot, dilation)

Question 37

What data should be included in the assessment of the afterload status in patients with cardiac problems at the bedside without invasive monitoring?

Answer 37

1. BP 2. Temp 3. Hx of valvular stenosis 4. Hx of pulmonary diseases 5. Medications that can cause changes in vasomotor tone or myocardial contractility

Question 38

What do your stupid teachers think about contracility?

Answer 38

Contractility refers to the force of myocardial muscle contraction. Factors that positively affect contractility, thus increase the force of muscle contraction, are called positive inotropes. Factors that negatively affect or diminish the force of contraction of the myocardium are called negative inotropes. An increased contractility will result in an increase in stroke volume.

Question 39

What are some positive inotropes?

Answer 39

Medications such as: * Epinephrine * Norepinephrine * Digoxin * Calcium Exercise Sympathetic nervous system stimulation

Question 40

What are some negative inotropes?

Answer 40

Medications such as: 1. Beta blockers 2. Calcium channel blockers 3. Barbituates Myocardial ischemia Parasympathetic nervous system stimulation (rest and digest)

Question 41

What do your stupid teachers think about cardiac output?

Answer 41

Cardiac output is the volume of blood that is ejected from the heart per minute. For the body to function properly, the heart needs to pump blood at a sufficient rate to maintain an adequate and contiuous supply of oxygen and other nutrients to all organs. Cardiac output is dependent on both the HR and the stroke volume (SV). Factors that affect the CO include any alterations in either HR and/or SV. Stroke volume is affected by preload, afterload, and contractility.

Question 42

What is the normal CO range for an adult?

Answer 42

4-8 L /minute

Question 43

What happens when the patient experiences a low CO?

Answer 43

The heart tries to compensate by alterations in either HR or SV

Question 44

In the absence of hemodynamic monitoring, what non-invasive assessment data give the RN an indication of cardiac output?

Answer 44

1. BP 2. skin temp 3. CRT 4. HR and quality 5. UOP 6. LOC 7. Lung sounds

Question 45

What strategies can the RN incorporate to minimize valsalva?

Answer 45

1. Increase fluid intake 2. Stool softeners 3. Increase diber 4. Avoid holding breath with acitivity

Question 46

What activities can result in the valsalva meneuver and what is the effect on hemodynamic function?

Answer 46

1. When pt. takes a deep breath, holds it, traps air it increases intra-abdominal and intrathoracic pressure an ddecreases blood volume to the right atrium (reduces preload and CO) 2. Holding breath can also stimulate vagus nerve with temporary bradycardia, also decreased CO 3. When intra-thoracic pressure is released, increase in HR as heart accommodates change in volume and pressure 4. Patient with poor heart function may not tolerate and prone to fatal dysrhythmia 5. Elderly patients with heart failure, cerebral edema, HTN, CAD, recent MI increases risk

Question 47

What would you expect in a patient with a low ejection fraction?

Answer 47

Severe activity intolerance. Patient's enegy is being used for basic needs (breathing, heart beating, circulation, digesting). Expectations for total self-care unrealisitic - exhausted with minimal exertion. Assess for signs of worsening CO and assist patient to meet needs.';lk

Question 48

What other nursing diagnoses may apply in a patient with decreased cardiac output?

Answer 48

1. Activity Intolerance 2. Ineffective Tissue Perfusion 3. Fatigue

Question 49

How is an apical-radial pulse determined?

Answer 49

May be used to determine whether each heartbeat perfuses blood to the periphery. 2 nurses, 1 watch. 1st nurse listens to the apical pulse and 2nd nurse palpates the radial pulse during the same minute. Normal: should be the same number of beats Abnormal: apical pulse is higher than the radial pulse Other, less specific way: 1 nurse to auscultate apical and palpate radial at same time, heart beat should be followed by a pulsation at radial site

Question 50

What is the significance of a apical-radial pulse deficit?

Answer 50

A pulse deficit indicates diminished peripheral perfusion that could be aused vby decreased cardiac output. A pulse deficit greater than 5 could be significant