Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Perf Monitoring > Test 4 > Flashcards

Test 4 Flashcards

1
Q

5 phases of the cardiac Cycle

A

1) Isovolumetric Ventricular Contraction
2) Ventricular Ejection
3) Isovolumetric Relaxation
4) Ventricular Filling
5) Atrial Systole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Isovolumetric (putting out effort but not moving) Ventricular Contraction

A
  • wall tension of the ventricles increases
  • intraventricular pressures increase
  • mitral and tricuspid vavles close
  • pulmonic and aortic vavles remain closed (R of the QRS complex) until there is a certain amount of pressure in the ventricles
  • volume stays the same
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Mitral valve closes when

A

LV pressure exceeds LA pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Ventricular ejection

A
  • Pressure = flow x resistance
  • intraventricular pressure has risen and eventually the pressure exceeds the pressure in the pulmonary artery and aorta which results in the valves opening.
  • LV achieved maximum volume
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Ventricular ejection fraction

A
  • about 40-60% of blood in the ventricles is ejected

- EF=SV/EDV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

T wave created by

A

Ventricular repolarization toward the end of ventricular systole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Isovolumetric relaxation

A
  • Toward the end of ventricular systole, the pressure inside the ventricles fall below that of aorta and pulmonary artery
  • AV and PV valves slam closed and the MV and TV already closed
  • blood continues to fill the atria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Dicrotic notch

A
  • Reflective pressure wave as the aortic valve slams closed after ventricular systole
  • important for intra-aortic balloon pump (IABP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Rapid Ventricular Filling

A
  • Atrial pressure greater than ventricular pressure
  • MV and TV open
  • Blood flows passively from the pressurized atria into the ventricles
  • 70% of the ventricular filling takes place by PASSIVE PROCESS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Atrial Systole (Atrial Kick)

A
  • Coincides with late ventricular diastole

- ventricles receive a 30% boost from the atrial kick for more effective diastolic filling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

P wave

A

atrial depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Cardiac Output

A

CO= Heart rate x stroke volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Factors affecting stroke volume

A
  • Preload
  • afterload
  • contractility (inotropy)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Preload

A
  • Passive stretching of the ventricular walls
  • caused by the blood volume in the ventricles at the end of diastole (EDV)
  • Valvular insufficiency may allow backflow altering the EDV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Afterload

A
  • Resistance

- pressure the the LV must overcome to eject blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Contractility (inotropy)

A
  • Capability of the heart walls to contract after depolarization
  • ability to contract depends on how much fiber gets stretched at EDV and health of the fibers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Doplarization

A
  • electrical change of cell membrane potential making it less negative
  • Na+ coming in
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Repolarization

A
  • electrical change of cell membrane potential making it more negative to its resting state after depolarization
  • K+ leaving
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Nernst equation

A

EMF= (+or-61.5/valence)(log([inside]/[outside])

-Na, K, Ca, Cl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

SA node as the pacemaker

A
  • it does not require a stimulus to fire like most nerve cells
  • self-firing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

SA node ion potentials

A
  • SA node slowly leaks K+ out of the cell and slowly leaks Na+ into the cells (funny current)
  • when the leaks reduce the membrane potential to -40mV it hits the excitation threshold
  • once excitation occurs, you just can’t stop it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Cardiac conduction

A

Heart cannot contract and pump unless and until there’s electrical stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

automaticity

A

cell’s ability to spontaneously initiate an impulse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

excitability

A

cell’s responsiveness to an electrical stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

conductivity

A

cell’s ability to transmit electrical stimulus to another cell

26
Q

contractility

A

how well a cell contracts after exposure to a stimulus

27
Q

conduction

A

-electrical stimuli created by pacemakers cells usually travels through the heart via the CONDUCTION SYSTEM

28
Q

Conduction system pathway

A

SA node-> internodal tracts-> AV node-> Bundle of His-> right and left bundle branches-> purkinje fibers

29
Q

Conduction rate of SA node (affected by sympathetic or parasympathetic inervation)

A

SA node: 100 bpm

-not from an upstream source with a faster inherent rate

30
Q

Conduction rate of AV node (affected by sympathetic or parasympathetic inervation)

A

AV node: 40-60 bpm

-not from an upstream source with a faster inherent rate

31
Q

Conduction rate of purkinje fibers (affected by sympathetic or parasympathetic inervation)

A

Purkinje fibers: 20-40 bpm

-not from an upstream source with a faster inherent rate

32
Q

how electrical signals captured

A
  • via electrodes
  • amplified
  • then sent to a monitor producing an ECG
33
Q

ECG

A
  • voltage graph
  • 5 large blocks is a second
  • one large box is .20 seconds and .5 mV
  • each smaller box in the large box is .04 sec and each small box is .1 mV
34
Q

one ECG wave =

A

one cardiac cycle

35
Q

p wave

A
  • atrial depolarization

- first wave on ECG

36
Q

Q wave

A

first negative deflection (below isoelectric line)

37
Q

R wave

A

-first upward or positive deflection

38
Q

S wave

A

first negative deflection after the R wave

39
Q

T wave

A
  • ventricular repolarization/ recovery

- usually rounded upward immediately after QRS complex

40
Q

U wave

A
  • purkinje fiber repolarization (often not seen)

- usually only seen in slow heart rhythms

41
Q

PR interval

A
  • atrial impulse extending from the SA node through the AV node, bundle of his, and Right and Left branches
  • Starts at the beginning of the P wave and ends at the beginning of the QRS complex
  • normally .12-.20 seconds
  • greater than .20 seconds= conduction delay through the atria or AV junction
  • less than .12= the impulse started somewhere other than the SA node
42
Q

QRS interval/ QRS Complex

A
  • Follows P wave
  • measured from beginning of Q wave to End of S wave
  • REPRESENTS THE INTRAVENTRICULAR CONDUCTION TIME
  • Wide QRS may be due to MI or conduction delay (AV block)
  • “Notched” may be due to bundle branch block
43
Q

ST Segment (very important)

A
  • Represents the end of ventricular depolarization and the beginning of repolarization
  • VERY IMPORTANT in open heart Sx
  • Should be isoelectric (flat and at baseline)
  • depression may suggest acute MI or ischemia
  • elevation may suggest injury to the myocardium
  • OBSERVE BOTH PRE-OP AND POST-OP!
44
Q

QT interval

A
  • represents ventricular depolarization and repolarization
  • measured from beginning of QRS to end of T wave
  • length varies with rate (increased HR= short QT interval)
  • Normal: .36-0.44
  • prolonged QT= longer relative refractory period
  • short QT= hypercalcemia, digoxin toxicity
45
Q

Elusive U wave

A
  • purkinje/ ventricular recovery/ repolarization
  • not on every strip
  • upright and round
46
Q

8 easy steps to evaluating ECG’s

A

1) Are the atria and ventricles “regular”?
2) What’s the rate?
3) Evaluate the P waves
4) What’s the P-R interval duration?
5) What’s the QRS complex duration?
6) Evaluate the T waves
7) What’s the Q-T interval?
8) “Other” (ectopic beats, abnormal rhythms, unique rate characteristics)

47
Q

Are the Atria and Ventricles regular?

What to look at

A
  • measure P to P interval (atrial regularity)

- measure R to R interval (ventricular regularity)

48
Q

Whats the rate?

A
  • the 10x method
  • 1500 method (# of small squares between P-P and divide 1500 by that #)
  • Bradycardia= 100bpm
49
Q

Evaluate the P waves

A
  • Are they present?
  • is there one P wave for every QRS complex
  • normal size and shape?
50
Q

What is the P-R interval duration

A
  • Should be .12-.20 seconds
  • is the interval constant
  • is there QRS complex for every P wave
51
Q

What is the QRS complex duration

A
  • Normal .06-.12
  • Prolonged suggests a conduction delay through ventricles (ischemia, electrolyte abnormalities, drugs)
  • Is the shape normal for that lead
52
Q

Evaluate T waves

A

-are they present?
-normal shape?
-if peaked= hyperkalemia
-inversion is normal in peds and yound females
-other causes of T wave inversion = ischemia, pulmonary emboli,
cardiomyopathy, electrolyte abnormalities

53
Q

What is the Q-T interval

A
  • Normal: .36-.44 seconds
  • # of small boxes from beginning of the QRS Complex to the end of the T wave and returning to baseline and multiply by .04
54
Q

PR interval >.20 suggests

A

-Conduction delay through atria or AV junction

55
Q

PR interval

A

-impulse started somewhere other than SA node

56
Q

QRS interval Wide may be due to

A

-MI or conduction delay (AV block)

57
Q

QRS interval “notched” may be due to

A

bundle branch block (RBBB or LBBB)

58
Q

ST segment depression may suggest

A

-acute MI or ischemia

59
Q

ST segment elevation may suggest

A

-injury to the myocardium

60
Q

QT interval prolonged

A

-longer relative refractory period

61
Q

QT interval short

A

hyercalcemia

62
Q

Elusive U wave seen prominently in

A

hypercalcemia and hypokalemia

Perf Monitoring (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions