Cardiac Flashcards
Cardiac Index
-More specific indicator of hemodynamic status than CO
- CI = CO/BSA
Cardiac Output
HR x SV
MAP
-Takes into account that diastole is 2/3 of cardiac cycle
- MAP = 2 (DBP) + (SBP) /3
Ejection Fraction
-Amount of blood ejected from LV compared to total available
- Should be over 50%
Bainbridge Reflex
- Reflexive hypertension caused by stretch of right atrial receptors
-Speeds up if HR becomes overloaded to equalize pressure
PAOP
Pulmonary artery obstructive pressure
- pressures in L side of heart and pulmonary filling pressures
- balloon inflates until it “wedges” into PA
-turbulence behind the balloon is blocked and it senses what is in front of it (pulmonary vascular bed) and L side of heart
- Normal is 5-12
What does high LAP indicate?
Mitral valve dysfunction
What does high RAP indicate?
Pulmonic stenosis, tricuspid regurgitation
Your pediatric patient has the following parameters.
HR 80
BP 100/60
SV 40
BSA 0.9 m2
The cardiac index for this patient is:
First calculate cardiac output, HRxSV
80x40=3200 = 3.2L/min
Then use CI=CO/BSA
3.2/0.9 = 3.55L/min/m2
Normal is 2.5-4.0 L/min/m2
Calculate the cardiac output for a 16 year old with HR of 72 and stroke volume of 70
70x40=5040=5.04L/min
What is the MAP for a patient with a BP of 110/50 and HR of 80?
MAP = 2(DBP) + (SBP) /3
2x50 = 100 + 110 = 210 /3 = MAP 70
Which of the following would be considered normal value for an ejection fraction ?
A. 25%
B. 35%
C. 40%
D. 60%
D. 60%
EF should be over 50%
EF is the amount of blood ejected from the LV compared to the total amount available. 35% or less indicates a problem with contractility, outflow, or filling
Which of the following statements is true about events that occur during a normal cardiac cycle?
A. Metabolism in the heart is unchanged during diastole.
B. Metabolism of the heart is decreased during diastole.
C. An increase in cardiac output increases diastole.
D. Diastole compromises about 40% of the cardiac cycle.
B. Metabolism of the heart is decreased during diastole, which accounts for approximately half of the cardiac cycle at birth. Shortly after birth, the diastolic phase lengthens so that it represents 2/3 of the cardiac cycle. An increase in cardiac output decreases diastole.
A reflex tachycardia caused by stretch of RA receptors is known as
A. The Herring-Sines law
B. The Bainbridge reflex
C. Starling’s law
D. The renin-angiotensin system
B. The Bainbridge reflex
Believed to occur to speed up the HR if the right side becomes overloaded and help equalize pressures in both sides.
Your patient requires placement of a LA pressure monitoring line. The pressure reads 18mmHg. This value might indicate
A. Pulmonary embolism
B. Pulmonic stenosis
C. Tricuspid regurgitation
D. Mitral valve dysfunction
D. Mitral valve dysfunction
LAP is usually 8. Pulmonic stenosis or tricuspid regurgitation would cause high RA pressures.
Which of the following is true regarding the 4th heart sound (S4)?
A. S4 occurs just after the first heart sound
B. The 4th heart sounds occurs with ventricular contraction.
C. The 4th heart sound is benign.
D. The 4th heart sound is always pathologic after 24hrs of life.
D.
Indicates a decreased ventricular compliance.
Produced when an anthill contraction fills up the ventricle. Rarely heard in newborns, heard right before the S1 sound. During the first 24hrs of life, S3 may be heard just after S1 and sounds like a click.
The mean pressure difference in the systemic vascular bed divided by blood flow is known as
A. LAP
B. SVR
C. PCW
D. PVRI
B. SVR
Indicates the resistance the LV must pump against
A heart murmur associated with acute valvular regurgitation is called
A. S3
B. S2
C. S1
D. S4
D. S4
S1 and S2 are normal sounds. S3 is associated with fluid status. S4 is associated with ventricular compliance.
Stroke volume is composed of which of the following factors?
A. Viscosity, blood volume, and impedance
B. CO, HR, compliance
C. Contractility, preload, and afterload
D. Systemic impedance, HR, compliance
C.
With only minute changes in afterload, the stroke volume can fall significantly
Your patient was admitted for severe dyspnea, dysphagia, palpitations, and an intractable cough. On auscultation, you hear a loud S1 and a right-sided s3 and s4. A PA Cath is placed and large A waves are seen in the PAOP tracing. The patient probably has
A. Mitral stenosis
B. Myocarditis
C. Atrial stenosis
D. Mitral insufficiency
A.
Large A waves are seen with increased pressure during atrial contraction. The pattered could be caused by mitral stenosis, an ischemic LC, or failure of an LV
Pt comes in with a popliteal BP higher than the brachial BP by at least 30mmHg. This indicates
A. DeRoge’s sign
B. Hill’s sign
C. Holmes’ sign
D. Rochelle’s sign
B. Hill’s sign is popliteal BP higher than brachial by 20 points or more. Reflects the rapid rise in pulsation found in patients with aortic insufficiency. DeMusset’s sign is also found in aortic insufficiency - the bobbing of head in time with forceful pulse
Pulsus Arternans is most often noted with
A. Mitral stenosis
B. Constrictive pericarditis
C. Left ventricular failure
D. Aortic stenosis
C.
Weakened myocardium can’t maintain an even pressure with each contraction, causing pulses to alternate between strong and weak.
Left vs Right sided heart failure
Left: Lungs
Right: Rest of body
