Flashcards in Basic Arrhythmias Deck (77):
0
What are the two types of cells in the heart?
Electrical cells
Mechanical cells
1
What do electrical cells do?
Initiate and conduct impulses
2
What do mechanical cells do?
Contract in response to stimulation
3
What is polarization?
Electrical charges are balanced and ready for discharge
4
What is depolarization?
Discharge of energy that accompanies the transfer of electrical charges across the cell membrane
5
What is repolarization?
Return of electrical charges to original state
6
What part of the heart pathway stimulates the mechanical cells?
Perkinje fibers
7
What is the inherent rate of the SA node?
60-100
8
What is the inherent rate of the AV junction?
40-60
9
What is the inherent rate of the ventricles?
20-40
10
What determines what will be the pacemaker?
The site with the fastest rate
11
What is the normal pacemaker?
SA node
12
What is it called when a site speeds up and takes over as pacemaker?
Irritability
13
What is it called when the normal pacemaker slows down or fails and a lower site assumed pacemaker responsibility?
Escape
14
Sympathetic stimulation causes what three things with the heart?
Increase heart rate
Increase AV conduction
Increase irritability
15
Parasympathetic stimulation causes what three things in the heart?
Decreased heart rate
Decreased AV conduction
Decreased irritability
16
What does the sympathetic branch influence in the heart?
Both the atria and the ventricles
17
What does the parasympathetic branch influence in the heart?
Atria
18
Is it negative or positive inside a cardiac cell?
Negative
19
Is it positive or negative outside a cardiac cell?
Positive
20
What electrolyte is inside cardiac cells?
Potassium
21
What electrolyte is outside a cardiac cell?
Sodium
22
What is the isoelectric line?
Straight line produced on EKG machine that means no current is flowing
23
If the flow of electricity is toward the positive electrode what will the EKG machine produce?
An upward deflection
24
If the flow of electricity is toward the negative electrode what will the EKG machine produce?
A downward deflection
25
How much time in between two tic marks?
3 seconds
26
What does the height of the deflection indicate?
The voltage
27
Which lines measure voltage?
Horizontal
28
Which line measures time?
Vertical lines
29
How much time is in between two heavy vertical lines on an EKG graph?
.20 seconds
30
How much time is in between two lite vertical lines on an EKG graph?
.04 seconds
(1/5th the time of bold vertical lines)
31
What are the five waves called in a single cardiac cycle?
P
Q
R
S
T
32
What does an interval refer to?
In the area between the waves
33
What does a segment referred to?
A straight line or area of electrical inactivity between waves
34
What wave is indicative of atrial depolarization?
P wave
35
What is the PR segment indicative of?
The delay in the AV node
36
What area of the heart is the slowest conduction speed?
AV node
37
Why does the AV node have the slowest conduction speed?
To allow time for atrial contraction and complete filling of the ventricles
38
What does the PR interval monitor?
All electrical activity in the heart before the impulse reaches the ventricles
39
What is the first negative deflection?
The Q wave
40
What does the QRS complex indicate?
Ventricular depolarization
41
What is the first positive deflection following the P wave?
R wave
42
What is the second negative deflection following the P wave?
S wave
43
What wave indicates ventricular repolarization?
T wave
44
How long are normal PR intervals?
.12-.20 seconds
45
What does a long PRI indicate?
Delay in the AV node
46
How do you measure the PR interval?
Start at first deflection of p wave
End at final point of PR interval
Don't include QRS complex
47
How do you measure the QRS complex?
Include the beginning of Q wave
End at end of S wave
Do not include ST segment
48
What is the normal time range for QRS complex?
Less than .12 second
49
What are 4 causes for artifact on an EKG
Muscle tremors/shivering
Patient movement
Loose electrodes
60-cycle interference (Effect of other electrical instruments in room)
50
What two waves on an EKG are the refractory period?
QRS wave
T wave
51
What is the relative refractory period?
Small part of the refractory period where some of the charges are polarized and can be depolarizer if the impulse is strong enough
52
What is the refractory period?
Period when the heart is unable to respond to an impulse
53
What are the two refractory periods called?
Absolute refractory period
Relative refractory period
54
What is the absolute refractory period?
When absolutely no impulse can cause depolarization
55
When is the relative refractory period?
Downward slope of T wave
56
When is the absolute refractory period?
QRS interval until the apex of T wave
57
Where is the positive electrode placed?
Apex of heart
58
Where is the negative electrode placed?
Below right clavicle
59
Where is the ground electrode placed?
Below left clavicle
60
What are four of the most common major categories arrhythmias?
Sinus
Atrial
Junction
Ventricular
61
A normal healthy heart would be and what rhythm?
Normal sinus rhythm
62
What should the R wave correspond with?
Pts pulse
63
What does regularly irregular mean?
There's a pattern of irregularity
64
What does basically regular mean?
There's a regular rhythm with a beat or two that interrupts it
65
What does totally irregular mean?
There's no pattern at all
66
How do you determine if a rhythm is regular?
Measure RRI
R to R interval
67
To find the rate of a rhythm how much do you divide the total of the small squares?
1500
68
To find the rate of a rhythm how much do you divide the total of the large squares?
300
69
What does supraventricular mean?
Activity occurring above the ventricles
70
What part of the heart conductive system is the fail safe mechanism?
The AV node
71
What does fail safe mechanism mean?
The AV node protects the ventricles from having to respond to too many impulses from the atria
72
A QRS of less than .12 second is what in origin?
Supraventricular
73
What occurs if there is a conduction disturbance in the ventricles?
A wide QRS complex
74
What is afterload?
Resistance heart must pump against
75
What is preload?
The pressure on the ventricles at end of resting phase
76