Test 3 Ch.11 Flashcards
1
Q
The primary indication for hemodynamic monitoring is the management of
A
critically ill pts who demonstrate evidence of compromised cardiovascular function
2
Q
hemodynamic monitoring can be used for the diagnosis and treatment of life-threatening conditions such as (9)
A
- shock
- heart failure
- pulmonary hypertension
- complicated myocardial infarction
- ARDS
- chest trauma
- burn injury
- severe dehydration
- after cardiac surgery
3
Q
Invasive Hemodynamics monitoring requires
A
the insertion of arterial and intracardiac catheters
4
Q
Measurements typically include (5)
A
- systemic arterial pressure
- central venous pressure
- pulmonary artery (PA) pressures
- arterial and mixed venous blood gases
- cardiac output (CO)
5
Q
These measurements can be used to calculate (5)
A
- O2 delivery (DO2)
- cardiac index (CI)
- stroke index (SI)
- vascular resistance
- cardiac work
6
Q
The benefits must out weigh the risk in these critically ill pts
A
something to know
7
Q
The output of the right and left ventricles are ultimately influenced by 4 main factors, what are they?
A
- Heart rate
- Preload
- Contractility
- Afterload
8
Q
What is an individual’s HR defined as?
A
the number of times the heart beats per minute
9
Q
HR can vary considerably depending on what? (5)
A
- pt’s age
- body habitus
- core temperature
- level of activity
- psychological state
10
Q
In a normal healthy adult, HR can range from
A
50 - 200 bpm
11
Q
What is preload?
A
The filling pressure of the ventricle at the end of the ventricular diastolic, and is estimated by measuring the end-diastolic pressures
12
Q
What is diastole?
A
When the ventricles are relaxed
13
Q
What does it mean if the bottom # on BP is greater than the top #?
A
The heart is never at rest
14
Q
The amount of blood present in the ventricles at the end of ventricular diastole (preload) depends on the level of
A
venous return and compliance of the ventricle
15
Q
Preload reflects the
A
length of the ventricle muscle fibers to generate the necessary tension in the next ventricular contractions
16
Q
The basic principle of cardiovascular physiology is sometimes called the
A
Frank-Starling mechanism or length-tension relationship
17
Q
The right ventricular end-diastolic (RVEDP) is typically used as an indictor of
A
right ventricular preload
18
Q
The left ventricular end-diastolic pressure (LVEDP) is used to estimate
A
left ventricular preload
19
Q
To estimate RVEDP and LVEDP what measurements do Clinicians rely on? (2)
A
- right atrial pressure (RAP) or central venous pressures (CVP)
- PA occlusion pressure (PAOP)
20
Q
PAOP is equivalent to
A
pulmonary capillary wedge pressure (PCWP)
21
Q
Contractility is the
A
force that the ventricles generates during each cardiac cycle and can be estimated using the ejection fraction
22
Q
How is the ejection fraction calculated?
A
the ratio of the SV to the ventricle end-diastolic volume
23
Q
Afterload is defined as the
A
impedance that the left and right ventricles must overcome to eject blood into the great vessels
24
Q
We measure that impedance as
A
systemic and pulmonary vascular resistance
25
The systemic vascular resistance (SVR) is used to describe the afterload that the left ventricle must overcome to
eject blood in the systemic circulation
26
What does SVR measure?
The whole body
27
Which ventricle pumps out to the whole body?
left
28
The pulmonary vascular resistance (PVR) reflects the afterload that the
right ventricle must overcome to eject blood into the pulmonary circulation
29
Which ventricle pumps in the pulmonary circulation?
right
30
SVR is ___ times greater than PVR
10
31
Increases in afterload are associated with (think opposite)
reductions in CO
32
Decreases in afterload are associated with
increases in CO
33
What does Retrograde mean?
Moving in the opposite direction
34
Direct measurement of the systemic arterial pressure requires the insertion of a catheter into a **peripheral artery** such as the (3)
- radial
- brachial
- femoral
35
What techniques can be used to insert the catheter (2)
- percutaneous technique
- surgical cutdown technique
36
Percutaneous is used in what setting?
critical care
37
What must be performed before a radial catheter is inserted?
modified Allen test
38
Administering a systemic vasodilator (e.g., nitroprusside) or a pulmonary vasodilator (e.g., tolazoline) will reduce the SVR and PVR and result in an
increase in cardiac output
39
Perform a modified Allen test to ensure
refill time of 5 to 10 seconds
40
Infiltrate the skin around the insertion with
local anesthetic (e.g., lidocaine)
41
Percutaneously insert the catheter appropriately at a
30-degree angle
42
If the pulse is weak or inaccessible, what should be done to insert Catheter
surgical cutdown
43
What should you frequently monitor after insertion of catheter? (2)
- Insertion site of infection
- Extremity distal to insertion site for adequate circulation
44
catheter should be removed if: (3)
- There is a clot formation evidenced by difficulty w/ blood sampling or persistently damped waveform
- Extremity distal to the insertion site becomes ischemic
- Insertion site becomes infected (fever)
45
What are catheters placed in the vena cava or right atria called?
central venous lines
46
What do CVPs monitor?
right heart pressure
47
CVP catheters are usually inserted percutaneously into a large **central vein** such as: (3)
- internal jugular (most common)
- peripherally through the medial basilic
- lateral cephalic vein
48
During ventricle systole or atrial diastole, when the tricuspid valve is closed the pressure measured in the right atrium or vena cava reflects
the RAP
49
At the end of ventricular diastole atrial systole when the tricuspid valve is open
the pressure measured in the right atrium reflects right ventricular pressure (RVP)
50
The CVP measured at the end of ventricular diastole can be used to monitor
IV fluid administration and estimate the filling pressure or preload of the right ventricle (RVEDP)
51
CVP is also used to measure
fluid balance
52
When are pressure measurements usually performed?
during exhalation and when the pt is supine
53
The transducer is
zeroed at the level of the right atrium
54
What is the normal value of CVP
2 to 6 mm Hg (**UNITS MUST BE USED FOR TEST**)
55
What are the most common problems encountered w/ insertion of CVP are (3)
- pneumothorax
- hemothorax
- vessel damage
56
Why is pneumothorax a common problem w/ insertion of a CVP?
There is a high likelihood of puncturing a lung
57
What is the the placement of the catheter confirmed with?
chest xray
58
Right atrial pressure (RAP) is also called
central venous pressure (CVP)
59
Balloon-tipped, flow-directed catheter is also called
Swan-Ganz catheter or pulmonary artery (PA) catheter
60
Once you insert the catheter into the Intrathoracic vessel, the ballon is slightly inflated, so that the flow of blood carries it to where it needs to go
something to know
61
The balloon on the tip of the catheter is what we can inflate to get a heart measurement
something to know
62
The standard adult catheter is
110 cm increments in length and is available in 7 and 8 French (Fr) sizes (marked off in 10 cm increments)
63
As with systemic arterial catheters, a pressurized flush solution must be run through the catheter at a rate of
1 to 5mL/h to prevent clot formation within the catheter's lumen
64
Dual-lumen catheter have
one lumen that connects to the ballon located near the tip of the catheter and a second lumen that runs the length of the catheter and terminates at a port at the distal end of the catheter
65
Triple-lumen catheters have an
additional proximal port that terminates approximately 30 cm from the tip of the catheter or at the level of the right atrium
66
The third lumen can be used to measure (2)
right atrial pressures (RAP) or for administering IV meds
67
Thermodilution catheters incorporate a
thermistor connector, which contains electrical wires that connect to a thermistor located 1.5 inches (3 cm) from the tip of the catheter
68
When measuring CO using the thermodilution technique,
a bolus of 5 % dextrose (cold or room temperature) is injected through the catheter's third (proximal) lumen, which is positioned at the level of the right atrium
69
Thermodilution can estimate
CO with the thermistor connector
70
Cold solution goes past the thermistor and can measure what the CO is, based on the change in temperature
something to know
71
Table 11.3 Complications associated with PA catheterizations: Cardiac Arrhythmias (6)
- PVC
- Premature atrial contraction (PACs)
- V-tach
- V-Fib
- Atrial Flutter
- A-Fib
72
Table 11.3 Complications associated with PA catheterizations: Infection Procedure or insertion site (4)
- Infection
- Pneumothorax
- Air embolism
- Access vessel thrombosis
73
Table 11.3 Complications associated with PA catheterizations: Pulmonary circulation
- Pulmonary artery rupture or perforation
- pulmonary infarction
74
Table 11.3 Complications associated with PA catheterizations: Pulmonary Artery Catheter (4)
- Balloon rupture
- Catheter knotting
- Damped waveform
- Catheter whip or fling
75
Box 11.3 Causes of Abnormal Right Atrial and Pulmonary Artery Occlusion Pressure Values: Elevated Right Atrial Pressures (RAP) (6)
- Volume overload
- Right ventricular (RV) failure
- Tricuspid stenosis or regurgitation
- Cardiac tamponade
- Constrictive pericarditis
- Chronic left ventricular (LV) failure
76
Table 11.3 Complications associated with PA catheterizations: Elevated Pulmonary Artery Occlusion Pressure (PAOP) (6)
- Volume overload
- Left ventricle failure
- Mitral stenosis or regurgitation
- Cardiac tamponade
- Constrictive pericarditis
- High PEEP
77
Table 11.3 Complications associated with PA catheterizations: Low RAP or PAOP
Hypovolemia
78
The typical adult can maintain an adequate CO at heart rates of
40 to 50 bpm as long as SV increases proportionally
79
CO will increase with heart rates up to about
200 to 220 bpm, assuming that the pt responds normally to sympathoadrenal stimulation
80
Heart rates above 220 will decrease in CO b/c
diastolic filling time is reduced (decreased ventricular filling from reduced venous return)
81
What is the normal **systemic** arterial pressure in adults? (range)
With a normal mean arterial pressure (MAP)
90 to 140 mm Hg to 60 to 90 mm Hg;
70 to 100 mm Hg
82
Systemic **hypERtension** is when systolic arterial pressure is greater than ____ and diastolic pressure greater than ___
systolic > 140 mm Hg
diastolic >90 mm Hg
83
Systemic **hyPOtension** is when systolic pressure is less than and diastolic pressure is less than
systolic < 100 mm Hg
diastolic < 60 mm Hg
84
An **increase** in diastolic pressure is associated with
vasoconstriction
85
A **decrease** in diastolic pressure is associated with
vasodilation
86
The RAP and the LAP are reported as
mean values rather than as systolic and diastolic values
87
The RAP (CVP) normally ranges from
2 to 6 mm Hg
88
The LAP as estimated from PAOP, ranges from
5 to 12 mm Hg
89
CVP and PAOP measures are commonly used to determine overall ______ _________
fluid balance
90
What does a low CVP or PAOP suggest?
hypovolemia
91
An elevated CVP or PAOP indicates (2)
hypervolemia or ventricular failure
92
The finding of bilateral infiltrates on a CXR along with a PAOP **greater than 25 mm Hg** suggest what?
The presence of cardiogenic pulmonary edema, resulting from left-sided heart failure
93
The finding of bilateral infiltrates on a CXR with a **normal** PAOP indicates what?
The presence of **noncardiogenic** pulmonary edema, resulting from damage to the alveolar-capillary membrane or ARDS
94
Cardiac output (Q) is the
volume of blood pumped by the heart per minute (L/min or mL/min)
95
Cardiac output (Q) normally ranges from
4 to 8 L/min
96
Stroke volume (SV) is the
volume of blood pumped by the heart per beat (L/beat or mL/beat)
97
Which one is lower PA systolic and diastolic pressures or systemic pressures
PA systolic and diastolic
98
What is the PA systolic pressure range for a healthy adult?
15 - 35 mm Hg
99
What is the PA diastolic pressure range for a healthy adult
5- 15 mm Hg
100
If VO2 and Q remain constant, the difference between the arterial O2 content and the mixed venous O2 content will
remain constant
101
When does mixed venous O2 values declined? (2)
- when arterial oxygenation is decreased
- Q is reduced
102
What does Oxygen delivery (DO2) represent?
The total amount of O2 that is carried in the blood to the tissues each minute
103
DO2 is the product of what 2 things?
Q and arterial O2 (PO2)
104
Under normal circumstances DO2 is approximately
1000 mL/min or about 550 to 650 mL/min/m2
105
When is DO2 increased? (2)
Q or arterial O2 content is elvated
106
A reduced DO2 indicates a (2)
decrease in Q or arteial O2
107
What disease process is DO2 increased in?
septic shock (hyperdynamic state)
108
DO2 is decreased in this medical issue
hemorrhage
109
What is a shunt defined as ?
A portion of the cardiac output that does not participate in gas exchange w/ alveolar air (perfusion without ventilation)
110
Shunts are usually identified as (3)
- anatomical shunts
- intrapulmonary shunt
- physiological shunt
111
Abnormal anatomical shunts can occur when
blood is allowed to bypass the pulmonary circulation and enter directly into the left atrium or ventricle, as occurs w/ atrial and ventricular septal wall defects
112
Intrapulmonary shunts occur when blood passes through
pulmonary capillaries that are not ventilated
113
What disorders can intrapulmonary shunts be caused by? (8)
- atelectasis
- pulmonary edema
- PNA
- pneumothorax
- complete airway obstruction
- consolidation of the lung
- ARDS
- arterial to venous fistuals (rare)
114
What is the normal ranges for SVR
900 to 1500 dyne x seconds x cm-5
115
Normal PVR ranges from
100 to 250 dyne x seconds x cm-5
116
What are the 2 most important factors that influence vascular resistance?
- the caliber of the blood vessels
- viscosity of the blood
117
The SVR is increased in left ventricle and hypovolemia arising from vasoconstriction caused by stimulation of the barorecpters
something to know
118
The SVR may increase in this disorder..
polycythemia
119
SVR decrease during systemic
- vasodilation, such as occurs w/ moderate hypoxemia
- vasodilators (nitroglycerin or hydralazine)
120
The PVR increases during periods of
- alveolar hypoxia or high intraavelor pressures are generated (ppv)
-
121
PVR decreases
vasodilator drugs such as tolazpline and prostacyclin
122
What are the normal range values for ejection fraction (EF)
0.5 to 0.7
123
EF values < _____ are associated w/ compromised cardiovascular function and imminent heart failure
0.30
124
The resting heart rate of a healthy adults is
60 to 100 bpm
125
Bradycardia
<60
126
Tachycardia
>100
127
CO will increase w/ heart rates up to ____ to _____ bpm assuming that the pt responds normally to sympathoadrenal
200 to 220
128
Can we measure BP w/ an Arterial line?
YES
129
What is the normal systemic arterial pressure for systolic (range)
90 to 140 mm Hg
130
What is the normal systemic arterial pressure for diastolic?
60 to 90 mm Hg
131
A normal mean arterial pressure ranges from?
70 to 100 mm Hg
132
When does a pt have systemic hypertension?
When systolic arterial pressures are greater than 140 and diastolic greater than 90
133
Systemic hypotension
systolic less than 100 mm Hg, diastolic less than 60 mm Hg
134
What is a critical MAP
60 mm Hg
135
Once MAP gets below 60 mm Hg it is very difficult to perfuse the body
something to know
136
What is a wide pulse pressure associated with?
an increased SV and decreased arterial compliance
137
What is a narrow pulse pressure associated with
a decreased SV and an increased arterial compliance
138
Right Atrial pressure (RAP) is also know as
Central venous pressure (CVP)
139
RAP can be monitored through the __________ lumen of a PA catheter or through a ______ line
proximal; CVP
140
Pulmonary artery pressure (PA) is measured by the __________ lumen of a PA cather
distal
141
Left atrial and ventricular can be measured during
PAOP (PCWP)
142
Left atrial pressure (PCWP) is measured when the
balloon is inflated (wedged). The measurement can only be obtained when you inflate the balloon
143
What can PAOP distingusih?
Cardiogenic pulmonary edema or non-cardiogenic pulmonary edema
144
Cardiogenic pulmonary edema is interchangeable with
increased pulmonary capillary hydrostatic pressure
145
Non-cardiogenic pulmonary edema is interchangeable with
normal pulmonary hydrostatic pressure or ARDS
146
Normal PCWP is
5 to 12 mm Hg
147
PCWP greater than ____ mm Hg means a pt has...
25;
Cardiogenic pulmonary edema
148
Tricuspid =
RIGHT SIDE of the heart
149
Mitrial=
LEFT SIDE of the heart
150
Normal PA systolic pressure is
15- 35 mm Hg
151
Normal PA diastolic pressire is
5- 15 mm Hg
152
Use of ______ levels at greater than ____ cm H20 can produce erroneously elevated pressure readings
PEEP;
15 cm H20
153
Pulmonary hypertension is determined by the
pulmonary artery pressure
154
Systolic greater than ___ and diastolic greater than ____ is considered ____________ ________________
35;
15;
pulmonary hypertension
155
Define CO
the volume of blood pumped out by the heart per min
156
Normal CO is
4 to 8 L/min
157
What is the equation for CO?
CO= SV x HR
158
Define Stroke Volume
the volume of blood pumped out by the heart per beat
159
What is a normal Cardiac index (CI)
2.5 to 4.0 L/min/m2
160
What is a normal Stroke index?
35 to 55 mL/beat/m2
161
What is a normal SaO2
98%
162
What is a normal CaO2
20 vol%
163
Can you start with normal arterial oxygenation and still have decreased venous oxygenation? and why?
Yes, b/c of shunting or increased oxygenation consumption (i.e., fever or exercise)
164
Can you start with a normal arterial oxygenation and still have a higher than normal (increased or elevated) mixed venous oxygenation? and why?
Yes, b/c the body is not using ANY of the oxygen (i.e., histotoxic hypoxemia). The body is not using it or its not delivering to the tissues
165
DO2 is the product of
CO and arterial O2 content and represents the total amount of O2 that is carried in the blood to the tissues
166
Normal DO2 is
1000 mL/min (1L/min) or about 550 to 650 mL/min/m2
167
DO2 is increased when
CO and CaO2 content is elevated hyperdynamic state (i.e., septic shock)
168
DO2 is decreased
when CO and CaO2 content is decreased (i.e., hemorrhage or anemic)
169
A shunt is the portion of the CO that does not
participate in gas exchange w/ alveolar (perfusion w/o ventilation)
170
Normal shunt is ____% to ____% of CO
2% to 3%
171
Shunt between 15 -20% we start to think of MV
something to know
172
Shunts 30% and greater we put them on MV
something to know
173
Vascular resistance represents the impedance or opposition to blood flow offered by the
systemic and pulmonary vascular beds and it influences the force that the ventricular must must generate during CO contraction
174
Calculation for SVR?
(MAP-CVP)/Q x 80
175
Calculation for PVR
(MPAP-PAOP)/Q x 80
176
What is the normal SVR?
900 to 1500 dyne x second x cm-5
177
What is the normal PVR
100 to 250 dyne x second x cm-5
178
SVR is increased if
blood viscosity increases as occurs in polycythemia
179
SVR is decreased during
systemic vasodilation (i.e., moderate hypoxemia)
180
PVR increases during periods of
alveolar hypoxia or in cases in which high positive pressure ventilation low CO
181
PVR is decreased by the administration of
pulmonary vasodilator drugs such as tolazoline and prostacyclin
182
Ejection Fraction (EF) provides an estimate of
ventricular contractility; how much blood is being ejected out of the ventricles
183
Normal EF is
0.5 to 0.7
184
EF less than _____ is associated w/ heart failure
0.30
