Introduction to Hemodynamic Assessment

Question 1

What is the basic tenet of resuscitation

Answer 1

Provide aqequate oxygen delivery to meet demand and reverse any existing tissue hypoperfusion

Question 2

What is systole and distole

Answer 2

Ventricular contraction and ventricular relaxation

Question 3

What is afterload

Answer 3

The pressure/resistance the heart has to overcome in order to pump

Question 4

What is the oxygen carrying portion of a red blood cell

Answer 4

Hemogloblin

Question 5

Why is having oxygen available for mitochondria so important

Answer 5

A larger amount of ATP can be made allowing for more energy

Question 6

What are the two MAIN hemodynamic goals in order to maintain tissue viability and function

Answer 6

Adequate tissue perfusion and adequate oxygen delivery

Question 7

What is a diagnostic clue of anaerobic respiration

Answer 7

Lactic acid

Question 8

What is the equation for Mean Arterial Pressure with regards to blood pressures

Answer 8

(1/3)SBP PLUS (2/3) DBP

Question 9

T/F: The arterial side is the driving pressure of the body so much it allows for ignoring venous flow

Answer 9

True

Question 10

In order to keep flow the same when blood pressure changes what factor has the most power, what is the factor within that factor that will overall change flow in autoregulation

Answer 10

Resistance, radius (vasoconstriction and vasodilation)

Question 11

T/F: Shock is when the autoregulation of blood flow is too low with blood pressure decreasing causing less blood flow

Answer 11

True

Question 12

What is the hemodynamic equation for MAP

Answer 12

Cardiac Output (pump performance) X Systemic Vascular Resistance (size of pipe system)

Question 13

What is a normal MAP

Answer 13

70-100 mmHg

Question 14

What is the afterload of the left heart, afterload of the right heart, which has the greater pressure the ventricle has to pump against

Answer 14

Systemic vascular resistance (SVR), Pulmonary vascular resistance (PVR), Systemic vascular resistance of` the left heart

Question 15

What is cardiac output, units, equation

Answer 15

measure of ventricular contractile performance, volume of blood (L) pumped by the ventricle per minute, CO = Stroke Volume X Heart Rate

Question 16

T/F: Cardiac output is the go to index

Answer 16

False: Cardiac Output can be varied greatly on the size of the patient

Question 17

What is the go to index and why, normal amount

Answer 17

Cardiac index, indexed for body surface area so it is universal regardless of size, 2.2-4 L/min/m2

Question 18

What the two major determinants of cardiac output

Answer 18

Heart rate, stroke volume

Question 19

Under normal circumstances as heart rate increases so does cardiac output, however at what heart rate is this no longer true and what are the two reasons why

Answer 19

150 beats/min, there is not enough time for the heart to fill with preload that would allow for meaningful contraction of the heart, increasing the heart rate with less oxygen causes a demand ischemia of the heart

Question 20

What concepts effect stroke volume

Answer 20

Preload (end-diastolic volume), contractility, 1/Afterload

Question 21

T/F: If the heart rate stays constant stroke volume will determine cardiac output

Answer 21

True

Question 22

What is the preload on the right side of the heart, left side

Answer 22

Central venous pressure, pulmonary capillary wedge pressure

Question 23

What are tow dynamic variables/tests for testing preload

Answer 23

passive leg raise and end-expiratory occlusion test

Question 24

What is the basic principle of the Frank-Sterling curve

Answer 24

As preload increases stroke volume and cardiac output increase

Question 25

What is arterial oxygen saturation (SaO2%), what is the normal

Answer 25

Oxygenation of arterial blood (proportion of hemoglobin saturated with oxygen), Normal: 95%- 100%

Question 26

What is the normal amount of oxygen that the tissues need to extract in order to function, shown in venous oxygen saturation (ScvO2)

Answer 26

25%/ 70-75%

Question 27

What is oxygen delivery (DO2) /Normal amount

Answer 27

Amount of oxygen delivered (transported) to tissues during a single cardiac cycle/ 1000 ml/min

Question 28

What is oxygen consumption (VO2)/Normal amount

Answer 28

Amount of oxygen uptake by tissues during a single cardiac cycle/ 250 ml/min

Question 29

What is oxygen extraction (O2ER)

Answer 29

Proportion of oxygen saturation taken by the tissues

Question 30

What is the relationship between oxygen extraction and oxygen delivery as delivery starts to decrease, what is the maximal oxygen extraction

Answer 30

As oxygen delivery decreases tissues increases the oxygen extracted from hemoglobin (inverse relationship) to meet oxygen needs, maintain oxygen volume for vital function, 50-60%

Question 31

T/F: In a clinical setting, low oxygen saturation (ScvO2) is an important warning sign for the inadequacy of delivery of oxygen to meet oxygen demands

Answer 31

True

Question 32

What value is the surrogate for knowing adequate tissue perfusion

Answer 32

MAP

Question 33

What is used as a clinical tool to determine right atrium pressure

Answer 33

Central venous pressure

Question 34

T/F: If the afterload is increased stroke volume increases

Answer 34

False:e If afterload is INCREASED the stroke volume DECREASES