Brainscape's Knowledge GenomeTM

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


See full index

PS 1 Study > ECG > Flashcards

ECG Flashcards

1
Q

Things you can detect on an ECG

A

cardiac rhythm, detection of myocardial ischemia and infarction, conduction system abnormalities, preexcitation, long QT syndromes, atrial abnormalities, ventricular hypertrophy, pericarditis

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

ECG is used in the evaluation of syncope. T/F

A

True

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

contraindications to performing an ECG?

A

No absolute contraindications to performing an ECG exist, other than patient refusal. Some patients may have allergies or, more commonly, sensitivities to the adhesive used to affix the leads; in these cases, hypoallergenic alternatives are available from various manufacturers.

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

Prep/positioning for ECG?

A

patient lying quietly in the supine position

skin is clean and trimmed of excess hair in the areas in which the leads are to be placed.

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

Which lead is placed at the fourth intercostal space at the right sternal border?

A

V1

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

Placement for lead V2?

A

Lead V2 is placed at the left sternal border directly across from lead V1, also in the fourth intercostal space.

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

Which lead is placed in the fifth intercostal space at the mid clavicular line

A

Lead V4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

due to obfuscation of bony landmarks in women with large breasts, it is recommended that the electrodes be placed overlying, rather than beneath, the breast. T/F

A

False

it is recommended that the electrodes be placed beneath, rather than overlying, the breast.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Steps in reviewing an ECG

A

Rate: Normal versus tachycardia versus bradycardia
Rhythm: Abnormal versus normal sinus
Intervals: PR, QRS, QT
Axis: Normal versus left deviation versus right deviation
Chamber abnormality: Atrial enlargement, ventricular hypertrophy
QRST duration: Q waves, poor R-wave progression, ST-segment depressions/elevations, or T-wave changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How much time does each ECG box represent

A

On the horizontal axis, each large box represents 0.2 seconds at a typical paper speed of 25 mm per second, which is then divided into five smaller boxes that each represent 0.04 seconds

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

Placement of lead V5?

A

lead V5 is placed in the same horizontal plane as that of lead V4 in the anterior axillary line or midway between leads V4 and V6 when the anterior axillary line is not readily discernible.

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

Placement of lead V6?

A

Lead V6 is placed in the horizontal plane of V4 at the mid-axillary line

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

What can be determined by the interval between 2 successive QRS complexes

A

Heart rate, when cardiac rhythm is regular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How to calculate heart rate on ECG?

A

300 / (no. of large boxes between 2 successive QRS complexes) bpm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The ECG displays a period of 8 seconds. T/F

A

F

the ECG displays a period of 10 seconds

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

How to obtain average heart rate when heart rate is irregular

A

If the heart rate is irregular, count the number of QRS complexes on the ECG and multiply by 6 to obtain the average heart rate in bpm (the ECG displays a period of 10 seconds; thus, 6 × 10 seconds = 60 seconds [1 minute]).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

P wave represents?

A

atrial depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The normal P wave morphology is upright in what leads?

A

I, II, and aVF, but it is inverted in lead aVR.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Abnormal p wave?

A

The P wave is typically biphasic in lead V1 (positive-negative), but when the negative terminal component of the P wave exceeds 0.04 seconds in duration (equivalent to one small box), it is abnormal.

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

What do you suspect with increased p wave duration

A

Left atrial enlargement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does right atrial enlargement look like on ECG?

A

Right atrial enlargement is associated with a peaked P wave taller than 2.5 mm in the inferior leads and more than 1.5 mm tall in leads V1 and V2.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What represents the time from the depolarization of the sinus node to the onset of ventricular depolarization

A

PR interval

23
Q

Normal duration of PR interval?

A

between 0.12 to 0.20 seconds.

The measurement starts from the beginning of the P wave to the first part of the QRS complex

24
Q

Ventricular depolarization ECG?

A

QRS complex

25
Q

Normal duration for QRS complex

A

0.06 to 0.10 seconds

26
Q

ST segment?

A

interval between ventricular depolarization and ventricular repolarization.

27
Q

QT interval

A

The QT interval measures the depolarization and repolarization of the ventricles. QT prolongation is associated with development of ventricular arrhythmias and sudden death.

The QT interval is dependent on the heart rate. A faster heart rate leads to a shorter QT interval, whereas a slower heart rate leads to a longer QT interval.

28
Q

Positive deflection in ECG?

A

A positive deflection is when the direction of the overall electrical activity is toward that lead.

29
Q

Where does normal cardiac axis lie?

A

The normal cardiac axis is expected to lie between -30º and 90º, which means the overall direction of electrical activity is toward leads I, II, and III.

30
Q

if the QRS complex is upright in both leads I and II, is the axis deviated?

A

if the QRS complex is upright in both leads I and II, then the axis must fall somewhere between -30º and 90º and the axis is normal.

31
Q

Lead AVR should always be negative. T/F

A

True

If not, possible limb lead reversal

32
Q

Axis deviation if the complexes are negative in lead I and positive in lead aVF

A

Right axis deviation

33
Q

Causes of right axis deviation

A

normal variation
right ventricular hypertrophy, left posterior fascicular block, ventricular ectopic beats, preexcitation, and dextrocardia

34
Q

Axis deviation if the complexes are positive in lead I but negative in lead II

A

Left axis deviation

35
Q

The causes of left axis deviation include

A

normal variation, left ventricular hypertrophy, left anterior fascicular block, congenital heart disease with primum atrial septal defect or endocardial cushion defect, ventricular ectopic beats, and preexcitation syndromes.

36
Q

Inferior leads

A

II, III and AVF

37
Q

Drugs that slow AV node conduction

A

Beta blockers and calcium channel blockers. They also slow the rate of SA node firing and therefore reduce heart rate

38
Q

What can prolong QRS intervals?

A

Bundle branch blocks or drugs that slow ventricular depolarization

39
Q

What can prolong QT interval?

A

drugs that block ventricular repolarization

40
Q

How does slowing heart rate affect diastole

A

Increase

41
Q

What is R-R interval

A

Distance b/w QRS complexes

Used to determine heart rate

42
Q

Slower heart rate on EKG?

A

Decrease in SA node firing rate

Increase in R-R interval, QT interval, and time of diastole

43
Q

Reasons for increased R-R intervals at slower heart rates

A

Ventricular depolarization takes longer, therefore QT interval prolongs
Also, at slower HR, it takes longer for the heart to generate a new P wave, time in diastole increases

44
Q

How does a fall in sinus rate affect diastole?

A

Increase it

45
Q

Conduction through where occurs after atrial depolarization (Start of P wave) and before ventricular depolarization (start of QRS complex)

A

Conduction through the AV node, HIS bundle, bundle branches and purkinje fibers

46
Q

Prolonged conduction through any of these structures can increase the PR interval

A

AV node, HIS bundle, bundle branches and purkinje fibers

47
Q

Which interval is affected by bradycardia and tachycardia

A

Q-T interval

48
Q

Prolonged Q-T interval

A

anything over 500 ms

T wave extends beyond halfway point between 2 QRS complexes

49
Q

Examples of Q-T prolonging medications

A

many antiarrhythmic drugs and macrolide antibiotics

50
Q

Classic findings of hypokalemia

A

Muscle weakness, U waves on ECG

Loop diuretics increase potassium excretion (eg furosemide given in congestive heart failure)

51
Q

Hyperkalemia?

A

Muscle weakness,
No U waves
Peaked T waves

52
Q

Hypercalcemia?

A

short QT interval
Volume depletion
Confusion

53
Q

Hypocalcemia

A

Prolonged QT interval
Muscle spasms
Tetany

54
Q

Conduction velocity, fastest vs slowest

A

Purkinje>Atria>Ventricles>AV node

PS 1 Study (35 decks)

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