Exam 1 Flashcards
1
Q
Label the following.
A
See picture
2
Q
What is Free H2O clearance, what is it regulated by & what does a high number mean?
A
How much pure H2) is removed from the blood. Regulated by ADH & high # means getting rid of a lot of water.
3
Q
What is the systemic pulse pressure?
A
100mmHg
4
Q
What is the CVP in a healthy person & where is it measured?
A
It should be 0 & is measured outside the RA.
5
Q
Where are is low & high compliance found?
A
Low compliance is on arterial side & veins have a high compliance.
6
Q
What is the meaning of pulse pressure?
A
It relates to how stiff vessels are. Low PP means more flexible. High PP means stiffer (arteries).
7
Q
Where is turbulent flow found & what is another function of it?
A
In the Aorta & acts as a volume reservoir.
8
Q
What is another word for compliance?
A
Elasticity. Higher elasticity means higher compliance= more stretch.
9
Q
What does elastance mean?
A
How rigid something is. It is the inverse of compliance. High elastance = low compliance.
10
Q
What kind of compliance is found in the pulmonary system?
A
High compliance due to low resistance.
11
Q
What do vasopressors not innervate?
A
Capillaries & cranial sinuses.
12
Q
Which has a higher velocity, aorta or vena cavae?
A
Aorta
13
Q
What tells arterioles to relax & increase flow?
A
Waste products
14
Q
What are the colloid pressures of Albumin, Globulins, & Fibrinogen?
A
21.8, 6, & 0.2 (mmHg)
15
Q
What is normal lymphatic flow & what is max?
A
2L/day & max is 40L/day
16
Q
Where does the lymphatic system drain into & what controls the flow?
A
The subclavian vein. Controlled by skeletal muscles.
17
Q
Do the lungs have a lymphatic system?
A
Yes, but it does not work as well as the systemic one.
18
Q
Where would one encounter negative venous pressures?
A
In the cranial sinuses
19
Q
If a healthy person with a BP of 120/80mmHg has their BP measured on their thigh, what reading would be expected?
A
160/120 mmHg
20
Q
BP at the femoral artery bifurcation would be?
A
142/102 mmHg
21
Q
If a BP is measured on a healthy person’s wrist & it reads 150/110 mmHg, how much arm distance is below the heart?
A
40.8cm (1.36cm for each 1 mmHg increase.
22
Q
What is the formula for Vascular compliance?
A
Compliance= Delta volume / Delta pressure
23
Q
High volume and low pressure result in ____ compliance?
A
High
24
Q
What are normal pulmonary pressure?
A
25/8 mmHg (16 mmHg)
25
What is the pulmonary Delta P?
14 mmHg (MPAP= 16 mmHg & LA pressure = 2 mmHg)
26
What is the normal pressure range for the RA?
0-4 mmHg
27
What is the normal pressure range for the RV?
0-25 mmHg
28
What are the normal pressure ranges for LA & LV?
LA= 2-5 mmHg & LV= 2-120 mmHg
29
What is the formula for vessel velocity?
- Velocity= Flow (5L/min) x cross sectional area of vessel
- Cross section: Radius squared x 3.14
30
What are the beginning pressure, end pressure & Delta P of capillaries?
Beginning= 30 mmHg, end= 10mmHg, Delta P= 20mmH
31
What is the capillary colloid pressure?
28mmHg
32
What is the interstitial fluid pressure?
-3mmHg
33
What is the average pressure inside a capillary?
17mmHg
34
What are the πp & g/dL of Albumin, Globulins & fibrinogen?
- Albumin: 21.8 mm Hg & 4.5 g/dL
- Globulins: 6 mm Hg & 2.5 g/dL
- Fibrinogen: 0.2 mm Hg & 0.3 g/dL
35
Sympathetic vasoconstriction releases _____?
Norepinephrine
36
What is normal intrathoracic pressure?
-4mmHg or -5cm H2O
37
What structural pressure is not affected by gravity?
Jugular veins
38
Veins are ___ times more/less _____ than arteries.
8, more & distensible
39
What is the formula for vascular distensibility?
Vd= Increase in Volume / (Increase in Pressure x Original volume)
40
What is the formula for Delta P?
Delta P= F x R (Flow times Resistance)
41
What is the formula for Flow?
- F= π △Pr4 / 8 η l
- [ (π times Delta P times radius to 4th power) / 8 times viscosity times length) ]
42
Conductance is proportional to?
Diameter to the 4th power
43
Small volume to large volume means?
High distensibility
44
How wide are the water-filled channels in an endothelial cell?
40Å (Angström) or 0.004 micrometers
45
What is the formula for predicting turbulent flow?
Re= [ (v x d x p) / η ]. (velocity x diameter x density / viscosity)
46
____ pressure & ____ velocity= low compliance.
High & low
47
Vascular resistance in CGS units is given how?
In dyne sec / cm-5
48
How to convert CGS units to regular?
1333 x mm Hg / ml/sec
49
What kind of sensors are carotid baroreceptors?
Stretch sensors
50
Aortic baroreceptors are controlled by the ____ thru the ____?
Medulla NTS (nucleus tractus solitarus & Vagus nerve
51
The carotid & aortic baroreceptors function at the same pressures?
False the aortic receptors function at a BP 20-30mmHg higher.
52
The carotid baroreceptors receive their signal from the ___, which then sends it thru the ___ & then thru the___?
Medulla (NTS) & Glossopharyngeal nerve & Hering’s nerve
53
If someone was to have no baroreceptors, it would result in?
Higher BP fluctuation.
54
If both carotid arteries were to be clamped, what happens to the BP?
Is will increase.
55
What is normal ESV?
50cc
56
What all happens in phase 1?
Filling, ESV=50cc, AV valves open, high atrial pressure, low intraventricular pressure
57
What is the normal EDV?
120cc
58
What all happens in phase 2?
Isovolumetric contraction, AV valves close, all 4 valves are closed at the beginning
59
What all happens in phase 3?
Ejection, peak pressures at 120mmHg, aortic valve closes @100mmHg
60
What all happens in phase 4?
Isometric relaxation, all 4 valves are closed, ESV= 50cc
61
What happens during the 1st part of Phase 3?
- 70% (49cc) of SV is ejected,
- LV pressure higher than aortic pressure,
62
What happens during the 2nd part of Phase 3?
- 30% (21cc) of SV is ejected
- at end aortic pressure > LV pressure
63
What happens during the 1st part of Phase 4?
Rapid filling of LV (50cc --> 100cc)
64
What happens during the 2nd part of Phase 4?
10cc of LV filling
65
What happens during the 3rd part of Phase 4?
Atrial kick filling ~10cc
66
What does the A wave signify?
- Atrial contraction,
- Short increase in CVP
67
What does the C wave signify?
- Bowing of A-V valves back into atria &
- Ventricles contract at this time
68
What does the V wave signify?
- Volume building up in atria &
- At end A-V valves open up
69
What is the 1st heart sound?
A-V valves closing
70
What is the 2nd heart sound?
Aortic valve closing
71
Why does the 1st heart sound vibrate more than the 2nd?
The aortic valve is meatier & doesn’t vibrate as much
72
Compare atrial kick in a healthy vs sick heart?
- In a healthy heart it contribute 5-10% &
- In a sick heart it contributes 20-25%
73
EW increases with increased _____ or _____?
Afterload & volume
74
A RA pressure of -4 mmHg will results in?
6L venous return
75
A RA pressure of 7 results in what?
A cardiac output & venous return of 0.
76
What is the system’s overall Delta Psf & what is another acronym for Psf?
- +7 mm Hg
- Ppv = Psf
77
Psf (systemic filling pressure) depends on what?
How much tone the system has & how full it is.
78
What causes a positive RA pressure?
CHF
79
What are causes for a negative RA pressure?
Hypovolemia, loss of sympathetic tone
80
A Psf of 14 mmHg results in how much venous return?
12L/min
81
A Psf of 3.5 mmHg results in how much venous return?
4L/min
82
How much blood do the arteries contain?
700cc
83
What does Pcv stand for?
Thoracic pressure
84
What is the max cardiac output for the RV alone?
13L/min
85
What is max sympathetic cardiac output?
25L/min
86
A left shift of the cardiac output curve results in what?
Increased CO & contractility
87
What are causes of a right shift of the cardiac output curve?
Parasympathetic stimulation, bad heart
88
What is a normal cardiac index & what is it for an 80y old?
Normal is 3.5 & 80y old is 2.4
89
What is TPR & what is another name for it?
Total peripheral resistance & SVR
90
What are causes for decreased TPR & increased CO?
Beriberi, AV shunts, anemia, hyperthyroidism, pulmonary disease, Paget’s disease
91
What are causes for increased TPR & decreased CO?
Removal of all 4 limbs, hypothyroidism
92
What is Beriberi?
- Vitamin B-1 (thiamine) deficiency (a co-factor for ATP production)
- S/S: High CO, right heart failure & lactic acidosis
93
Increased O2 consumption & metabolism leads to what?
Increased CO
94
What does Dinitrophenol do?
Uncouples normal metabolism. Leads to weight loss but increases body temp
95
Explain resistance to venous return (RVR).
- Increasing SVR --> increased resistance to venous return --> decreased venous return (L/min).
- Decreasing SVR --> decreased RVR --> increased venous return (L/min)
96
Halving & doubling RVR results in how much venous return?
Halving= 12L/min & Doubling= 4L/min
97
A right shift in the cardiac out thoracic pressure curve is caused by & what is needed to compensate?
- PEEP, tamponade &
- Increasing BP is needed to push blood into chest
98
What is the normal intrathoracic pressure?
-4 mmHg or -5 cm H2O
99
How does Nitroprusside affect CO & RA pressure?
Increases CO but does not affect RA pressure
100
How does nitroglycerin affect CO & RA pressure?
Decreases CO & RA pressure equally
101
How does a mixed vasodilator affect CO & RA pressure?
Slightly decreases CO & moderately decreases RA pressure
102
What is the 3rd heart sound?
Suggests left heart failure, mitral regurgitation, low EF, or restrictive diastolic filling
103
Label the following
See picture
104
What does the picture describe?
Increased Preload
105
Increased Preload results in?
- Increased EDV & SV.
- Slight EF increase.
106
Decreased preload will result in?
- Decreased EDV & SV.
- Slight EF decrease
107
Increased Afterload will result in?
- Increased aortic pressure.
- SV & EF decrease.
- ESV increases
108
Decreased Afterload will result in?
- Decreased aortic pressure.
- SV & EF increase.
- ESV decreases.
109
Increased contractility will result in?
- SV & EF increase.
- ESV decreases.
110
Decreased contractility will result in?
- Decreased SV & EF.
- Increased ESV.
111
Mitral stenosis leads to what & what is the compensation?
- Reduced preload --> lower SV, EDV & EF.
- Compensate via increased preload.
112
With what kind of valve issue will there be a decreased pulse pressure?
Aortic Valve stenosis
113
What is the 3rd heart sound?
- Not a valve
- A problem with a non-compliant ventricle.
114
Inspiration will shift the cardiac output curve to the___?
Left, due to blood being pulled into chest & increasing negative pressure.
115
What is mild, moderate & severe MR?
- Mild= <30cc
- moderate= 30-60cc
- severe= >60cc
116
What will ultimately result from MR?
Eccentric hypertrophy --> A-Fib
117
What shift will be seen on the pressure-volume loop with Mitral stenosis?
Left shift
118
What EKG changes will be seen with mitral stenosis?
- Prolonged P wave
- right axis deviation.
119
What results from mitral stenosis?
- Increased RV afterload
- Dilated LA
120
What conditions could be deadly for someone with MS?
A-fib & tachycardia due to decreased filling time.
121
What shift on the pressure-volume loop would AR cause?
Right shift due to increased intraventricular volume.
122
When does most aortic regurgitation happen?
At end of phase 4 as LV pressures are low.
123
What valve issue is the worst for someone with CAD?
Aortic stenosis due to increased wall pressures --> decreased coronary perfusion.
124
What pulse pressure will be seen with AS?
Narrowed pulse pressure.
125
Pulse pressure is related to___. Higher PP= higher___?
Contractility & contraction
126
In hemorrhagic shock when do CO & BP start dropping?
- CO @ 15% blood loss
- BP @ 20% blood loss
127
How much cardiac output is seen with 35% of blood volume loss?
50%
128
What is the most common shock?
Hypovolemic
129
What are 3 causes of decreased venous return?
- Low volume
- Low tone
- Obstruction
130
Air in an a-line will lead to an____ waveform?
Over dampened
131
What is the X descent?
- Atria relaxing
- Filling back up during mid systole
132
What is the V wave?
- Atria filling during late systole
- Building up pressure
133
What is the Y descent?
- A-V valves opening
- Early ventricular filling
- During early diastole.
134
What is the H wave/plateau?
Middle third of diastole
135
What affect will A-fib have on the CVP waveform?
- Prominent C wave,
- Loss of A wave
136
What affect will an AV block have on the CVP waveform?
Cannon A wave
137
What affect will TR have on the CVP waveform?
- Tall systolic C-V wave
- Loss of X descent
138
What affect will TS have on the CVP waveform?
- Tall A wave
- Attenuation of Y descent
139
What effect will RV ischemia have on the CVP waveform?
- Tall A & V waves
- Steep X & Y descents
- M or W configuration
140
What affect will pericardial constriction have on the CVP waveform?
- Tall A & V waves
- Steep X & Y descents
- M or W configuration
141
What affect will tamponade have on the CVP waveform?
- Dominant X descent,
- Attenuated Y descent
142
During normal breathing, the systemic MAP drops on ____ & LV output drops during___?
On early inspiration for both
143
What will prolonged positive pressure ventilation lead to?
Decreased venous return & decreased CO
144
How is SVR calculated?
[ (MAP – CVP) / (CO) ] x80
145
How is PVR calculated?
[ (MPAP – PAWP) / (CO) ] x80
146
The middle mediastinum contains what structures?
Heart, pericardium, ascending aorta, superior vena cava, pulmonary trunk, pulmonary veins, phrenic nerves, pericardiacophrenic aavv
147
What structures does the posterior mediastinum contain?
- Esophagus,
- thoracic aorta
- thoracic ducts
- vagus nerves
- azygos vein
- hemizygos vein
148
How is MR treated?
- Decrease afterload
- Tachycardia
149
What is normal coronary blood flow?
- 70mL/min/100grams of muscle
- 225mL/min
150
What does the inferior part of the heart rest on?
The central tendon
151
What is an S-2 split?
The aortic valve closes before the pulmonic valve due to the higher aortic pressures.
152
What all anchors the heart valve cusps?
Chordae tendineae & papillary muscles
153
What are the parts of heart valves called that touch each other when closed?
Lunule
154
What connects the pulmonic valve fibrous ring to the rest of the cartilaginous ring?
The tendon of conus
155
What is the posterior cusp of the aortic valve called?
Commissural cusp
156
What is another name for the PDA?
Posterior interventricular descending artery
157
Where is & what does the azygos vein do?
Carries blood from posterior (R) abdomen, chest, & heart to superior vena cava
158
Where is the Hemiazygos vein?
Behind the aorta, drains blood into the azygos vein
159
When is a PDA murmur the loudest?
During 2nd part of systole
160
When is an AS murmur the loudest?
During 1st to 2nd part of systole
161
What anchors papillary muscles?
Trabecula
162
What would the HR be without parasympathetic input?
Around 110
163
What are the 3 pericardial layers?
- Serous/visceral= thin & slippery not much connection to other 2
- Parietal layer= attached to fibrous layer
- Fibrous= doesn’t stretch much
164
What are the sound lengths of S1 & S2 & their pitch?
- S1= 0.14sec & low pitch
- S2= 0.11sec & high pitch
165
What does a S3 sound like & when is it?
Rattles during/near end of ventricle filling
166
When is a S4 heard & what is it?
- In a sick heart
- It’s atrial kick into a full ventricle (end of diastole)
167
When is MR heard?
- Beginning of systole.
- Sound depends on severity of MR
168
What sound pitch is better heard with a phonocardiogram?
Low pitch
169
What conditions increase chances of hearing abnormal (not real) murmurs?
- Hypothyroidism
- pregnancy
- anemia
- increased CO
170
How is coronary perfusion calculated?
Delta P of aortic pressure minus ventricular pressure
171
When is coronary perfusion the best & worst?
- Beginning of diastole &
- beginning of systole
172
Using coronary blood flow, how much does a healthy heart weight?
321 grams (225ml / 70mL= 3.21 x100grams= 321 grams
173
Aortic stenosis would be heard when, if relating to a specific EKG tracing part?
ST segment & ST interval
174
MS murmurs will be heard when on an EKG tracing?
TP & PR intervals
175
In AS the pulse pressure will be___ & in AR pulse pressure will be____?
Narrower & wider
176
Pulse pressure is related to___ & increased SV___ pulse pressure?
Contractility & increases
177
MR can be heard when on an EKG tracing?
QRS, ST segment & ST interval
178
Hearing S2 splitting would be when & due to what?
During inspiration due to increasing negative pressure, reducing pulmonic valve afterload, keeping valve open a bit longer.
179
Label the CVP waveform descents & waves in order.
A-wave, C-wave, X-descent, V-wave, Y-descent, H-wave/plateau
180
Which area of the heart is hardest to perfuse & why?
- Subendocardial arterial plexi.
- Subject to high wall pressures & sustained pressure due to inner cells depolarizing first & repolarizing last.
181
Concentric LVH is___ heart failure caused by___ & eccentric LVH is___ heart failure caused by__.
- Diastolic & AS
- Systolic & AR
182
What is the formula for EF?
EF= SV/LV EDV (70cc/120cc= 58.3%)
183
What can be used to reduce cardiac remodeling?
ACE inhibitor (growth factor inhibitor)
184
What is the BP pressure difference at the phlebostatic axis?
+ 6 mm Hg
185
At what Reynolds' number is flow turbulent?
>2,000
186
_____ velocity & _____ diameter lead to turbulent flow.
High & large
187
How does conductance & resistance relate?
Conductance= ( 1 / resistance )
188
What is another name for dicrotic notch?
Incisura (Lecture 1 slide 31)
189
Max sympathetic stimulation for CO is also called ____ & will shift the curve ____?
Hypereffect & left
190
When is S-4 heard?
Shortly before S1. Means increased ventricular diastolic stiffness
191
When is stroke work is increased?
With increased SV & increased afterload
192
What will cause shifts in the end-systolic pressure-volume relationship
Only contractility alterations will cause shifts in end-systolic pressure-volume relationship
193
How does AR affect BP, PP, EDV & LV pressures?
Aortic regurgitation: Aortic pressures fall faster & further than normal during diastole --> a low diastolic pressure & large pulse pressure. EDV & pressure are higher. Often it is stenotic & insufficient.
194
What is the formula for a change in pressure?
△P= △V / Ca
195
Decreased arterial compliance leads to ___ pulse pressure & ___systolic pressure?
Increased & increased
196
Increased SV leads to___ pulse pressure & ___systolic pressure?
Increased & increased
197
Aortic regurgitation has ___ SV & ___ diastolic pressure?
Increased & decreased
198
Aortic stenosis leads to ___SV, ___ pulse pressure & ___systolic pressure?
Decreased, decreased & increased
199
A decreased diastolic pressure means Resistance is ___ & conductance is ___?
High & low
200
Increased plasma osmotic pressure means filtration is ____?
decreased
201
What happens to the SNS, PSNS, HR, BP, & TPR in cushing's reaction?
- SNS increases
- PSNS decreases
- HR increases
- BP increases
- TPR increases
202
At beginning of exercise the CVP ____ & RVR ____?
Both increase. At max output the CVP > RVR
203
Examples that cause a right shift on the cardiac curve?
- open chest Sx
- tamponade
- blowing(trumpet)
- positive pressure ventilation
204
Examples causing a left shift on the cardiac curve?
- breathing against negative pressure
- taking someone off the ventilator
- decreasing intrathoracic pressure
205
Decreased venous compliance leads to ____ CVP?
increased
206
Anemia leads to ___ RVR & arteriolar ____, which leads to ___venous return?
- Decreased
- vasodilation
- increased
207
Examples of what increases RVR
- Increased venous return
- increased arterial resistance
- increased SNS activity
- obstructions
208
Beriberi is a deficiency in ____ leading to ____ & ____ cardiac output?
- thiamine
- vasodilation
- increased
209
How does adenosine affect the heart?
Increases coronary blood flow
210
In compensated heart failure, alodisterone & angiotensin 2 are?
Increased
211
A blowing sounding murmur means?
Insufficiency
212
If your patient's mean systemic arterial pressure changes, it must be because of changes in?
Cardiac output and/or TPR
213
What is the formula for tension?
T= P x r (Tension= Pressure x radius) Law of Laplace
214
Getting up after days in bed results in hypotension & dizziness, why?
Lying down results in increased CVP & baroreceptor firing --> increased renal activity --> fluid loss. When standing up there is decreased cerebral blood flow & the respiratory & skeletal pumps cannot compensate enough.
215
Why can BP rise very high during static exercises?
Muscles compression --> decreased blood flow
216
How does giving someone phenylephrine affect BP, SNS activity, contractility, TPR, HR?
- BP, TPR would increase.
- HR would decrease.
- Phenylephrine stimulates alpha-adrenergic --> increased BP --> increased baroreceptor firing --> decreased SNS activity & increased PSNS activity.
217
What would decreased renal & splanchnic blood flow despite an increase in MAP mean?
Increased sympathetic activity
218
Acute increases in arterial pulse pressure usually result from increases in stroke volume. True or false?
- True.
- Pp= SV/Ca (Pulse pressure= stroke volume / arterial compliance
219
An increase in TPR increases diastolic pressure more than systolic pressure. True or false?
False
220
At rest the patient has a pulse rate of 70 beats/min and an arterial blood pressure of 119/80 mm Hg. During exercise on a treadmill, pulse rate is 140 beats/min and blood pressure is 135/90 mm Hg. Use this information to estimate the exercise¬ related changes in the following variables: SV, CO & TPR?
- SV=Pp -> SV rest= 39cc. SV exercise= 45cc --> 6cc difference=15% increase.
- CO: CO rest= 70 x 39cc= 2.73L/min. CO exercise= 140 x 45cc= 6.3L/min. CO increased 2.3 times.
- TPR: MAP rest= 93, MAP exercise= 105. TPR= Pa/CO TPR rest= 93/2.73= 34mmHg. TPR exercise= 105/6.3= 16.7mmHg. TPR= 16.7mmHg / 34mmHg= 0.49= 49% decrease during exercise.
221
What is indicated by a normal MAP but very high arterial pulse pressure?
Increased arterial stiffness.
222
How would a stenotic aortic valve influence coronary blood flow?
- Increased LV pressures --> increased O2 use --> increased coronary flow. But high LV intraventricular pressures decrease flow.
- Resting O2 may be enough but cardiac reserve for exercise is not adequate
223
Which of the following will decrease the mean circulatory filling pressure?
- Increased circulating blood volume.
- Decreased arteriolar tone.
- Increased venous tone.
None
224
Severe dehydration would cause what kind of shift in the venous function curve?
Left shift
225
Which of the following would directly decrease CVP?
A) increased SNS activity
B) increased PSNS activity
C) Increased blood volume
D) Decreased TPR
Increased SNS activity
226
Consider the various components of the arterial baroreceptor reflex and predict whether the following variables will increase or decrease in response to a rise in arterial pressure?
– baroreceptor firing
– PSNS activity on the heart
– SNS activity on the heart
– Arteriolar tone
– Venous tone
– Peripheral venous tone
– TPR
– Cardiac output?
- Increase= baroreceptor firing rate, PSNS activity.
- Decrease= the rest.
227
Carotid massage in PSVT would do what?
Increased baroreceptor firing --> increased PSNS --> decreased HR &/or establishing normal rhythm
228
- Describe the immediate direct and reflex cardiovascular consequences of giving a healthy person a drug that blocks a,-adrenergic receptors.
- Describe the possible changes in mean arterial pressure, sympathetic nerve activity, cardiac output, total peripheral resistance, and shifts in the cardiac function and venous return curves?
- CO increases.
- TPR decreases.
- MAP decreases
- SNS activity increases(HR)
- Cardiac curve goes up
- Venous curve has no shift.
229
Whenever cardiac output is increased, mean arterial pressure must also be increased. True or false?
False. Increased CO usually decreased TPR but MAP could be same, lower or higher
230
Chronic elevation of arterial pressure requires that either cardiac output or TPR (or both) be chronically elevated. True or false?
True. Pa= CO x TPR
231
If resistance through an organ decreases what happens to TPR?
TPR decreases
232
Calculate TPR. MAP= 100mmHg, CVP= 0mmHg, CO= 6L/min?
1) R= △P/Q => TPR= (Pa – Pcv) / CO
2) TPR= (100-0) / 6L/min= 16.7mmHg x L/min
233
Determine Flow. Cap pressure= 28mmHg, Plasma oncotic= 24mmHg, tissue hydrostatic= -4mmHg, tissue oncotic= 0mmHg?
F= [28 – (-4) – 24 + 0]= +8mmHg
234
Increased Pulse pressure is related to which valve disease?
Aortic insufficiency
235
Calculate resistance to flow across this stenotic valve.
BP= 150/100mmHg,
LV pressures= 150/2mmHg,
LA pressures= 50/32mmHg,
HR= 60bpm,
SV= 50cc?
1) CO= 60bpm x 50cc= 3L/min.
2) R= △P/Q R= 30mmHg/3l/min= 10mmHg x L/min
236
What alteration in jugular venous pulsations might accompany third-degree heart block?
Irregular giant a-waves also called cannon waves
237
When is tricuspid regurgitation heard on an ECG tracing?
Right after S-1 --> close to S-2
238
Does 3rd degree HB cause an increased or decreased SV?
Increased SV due to lower HR= longer filling time
239
Pulmonic stenosis will cause what kind of axis shift?
Right axis shift
240
What is the definition of ejection fraction?
Ration of SV to EDV
241
P-wave in normal aVR lead will have what deflection?
Downward deflection
242
Decreased AV node conduction velocity will?
- Decreased HR,
- increase P-wave
- Increase PR interval
- widen QRS
Increase PR interval
243
Calculate EF.
EDV=150cc
ESV= 50cc?
1) SV= EDV – ESV= 100cc.
2) EF= SV/EDV= 100cc/150cc= 66.7%
244
Calculate CO.
- Male 70kg,
- SAO2= 200cc/L
- PAO2= 140cc/L
- VO2= 600cc/L
1) CO= 10L/min. Q= [ VO2 / (SAO2 – PAO2) ]
245
With all other factors equal, myocardial oxygen demands will be increased to the greatest extent by which of the following?
- increases in the heart rate
- increases in coronary flow
- increases in end-diastolic volume
- decreases in arterial pressure
- decreases in cardiac contractility
- Isovolumetric contraction uses most energy.
- Increased EDV will also increase O2 use but less than increased HR.
246
Four of these conditions exist during the same phase of the cardiac cycle and one does not. Which one is the odd one?
- The mitral valve is open.
- The ST segment of the ECG is occurring.
- The "v" wave of thejugular venous pulse hasjust occurred.
- Ventricular volume is increasing.
- Aortic pressure is falling.
ST segment occurs during systole
247
Increases in sympathetic neural activity to the heart will result in an increase in stroke volume by causing a decrease in end-systolic volume for any given end¬ diastolic volume. True or false?
True. Increased SNS activity --> increased contractility & EF
248
In which direction will cardiac output change if central venous pressure is lowered while cardiac sympathetic tone is increased?
- Need more info to properly answer question.
- Decreased preload decreases SV.
- Increased SNS will increase SV & HR.
249
Which of the following interventions will increase cardiac stroke volume?
- Increased ventricular filling pressure.
- decreased arterial pressure.
- Increased activity of cardiac sympathetic nerves.
- Increased circulating catecholamine levels?
All are correct.
250
How does a stenotic valve affect EDV, ESV, CO, flow?
- Flow is low due to high resistance.
- EDV is reduced.
-ESV is increased due to decreased CO.
251
A common Side effect of beta-blocker therapy is decreased exercise tolerance. Why is this not surprising?
Block the ability to increase HR & CO
252
Individuals with high arterial blood pressure (hypertension) are often treated with drugs that block beta-adrenergic receptors. What is a rationale for such treatment?
- Reduce HR & contractility --> decrease CO.
- Less flow through a constant = smaller pressure difference.
253
What direct cardiovascular consequences would you expect from an intravenous injection of norepinephrine?
Increased HR, contraction, arteriolar & venous constriction
254
How would a 10% diameter increase affect resistance?
- Resistance decreases by 32%.
- (R=1/r4th) R= 1/1.1 to the 4th --> 1/1.46 = 0.68%
