Basic & Advanced EKG (Exam I) Flashcards
1
Q
In what leads should a p-wave be positive?
A
- I, II, aVF, V4-V6
2
Q
What should the duration of a p-wave be?
A
- < 0.12 seconds
3
Q
What should the duration of a PR interval be?
A
- 0.1 - 0.2 seconds
4
Q
What should the duration of a QRS complex be?
A
- < 0.12 seconds
5
Q
Elevation/depression of an ST segment by __ mm is clinically relevant
A
> 1
6
Q
T-waves should be positive in which leads?
A
- I, II, V3-V6
7
Q
What does Paroxysmal mean?
A
Intermittent
8
Q
Venticular ectopy is usually indicative of what?
A
- K⁺ imbalances
9
Q
What effects do halothane/enflurane have in regards to arrhythmias?
A
- Halothane & enflurane sensitize the myocardium
10
Q
What arrhythmia in infants can result from sevoflurane?
A
- Bradycardia (via oculo-cardiac reflex?)
11
Q
What can desflurane cause during induction?
A
Prolonged QT
12
Q
What two adverse events can occur from local anesthetic injection into the vasculature?
A
- Severe bradycardia
- Asystole
13
Q
How would excessive intravascular lidocaine be treated?
A
- Lipid rescue
14
Q
What is the exhaustive list of conditions that can result in perioperative dysrhythmias?
(this card sucks)
A
- General anesthetics
- Local anesthetics
- Abnormal ABG or electrolytes
- Endotracheal intubation
- Autonomic reflexes
- CVP cannulation
- Surgical stimulation of heart/lungs
- Location of surgery
- Hypoxemia
- Cardiac Ischemia
- Catecholamine excess
15
Q
What anatomic structure (discussed in class) causes dysrhythmias when stimulated during cardiac surgeries?
A
- Pulmonary arteries
16
Q
What example was given of a surgical location where stimulation results in dysrhythmias?
A
- Eyes (due to oculo-cardiac reflexes)
- Heart/ (lungs)
17
Q
Where does lead V1 go? V2?
A
- V1 - 4th ICS, right of sternum
- V2 - 4th ICS, left of sternum
18
Q
Where does lead V3 go?
V4?
A
- V3 - between V2 and V4
- V4 - 5th ICS, left of sternum
19
Q
Where does lead V5 go?
V6?
A
- V5 - 5th ICS, left of sternum
- V6 - 5th ICS, left of sternum
20
Q
What wave is the first negative deflection after the p-wave on any lead?
A
- Q-wave
21
Q
What wave is the first positive deflection after a p-wave?
A
- R-wave
22
Q
Describe an s-wave.
A
- Negative deflection below baseline after an R or Q wave.
23
Q
What QRS is denoted by 1 in the figure below?
A
R
24
Q
What QRS is denoted by 2 in the figure below?
A
QS
25
What QRS is denoted by 3 in the figure below?
qRs
26
What QRS is denoted by 4 in the figure below?
rS
27
What QRS is denoted by 5 in the figure below?
qR
28
What QRS is denoted by 6 in the figure below?
rSR'
29
1 small box on an EKG strip equals _____.
1mm or 0.04s
30
1 large box on an EKG strip equals ______.
5mm or 0.2s
31
If healthy, both the QRS complex and T-wave should be ______ in leads I, II, & III.
positive.
32
What is the mean electrical axis of the heart?
59°
33
A clockwise shift of the mean electrical axis shift of the heart is indicative of what?
- Right-axis deviation
34
A counter-clockwise shift of the mean electrical axis shift of the heart is indicative of what?
- Left-axis deviation
35
Regarding Lead I, where is the negative terminal connected? How about the positive terminal?
Negative terminal = Right arm
Positive terminal = Left arm
36
Regarding Lead II, where is the negative terminal connected? How about he positive terminal?
Negative terminal = Right arm
Positive terminal = Left leg
37
Regarding Lead III, where is the negative terminal connected? How about the positive terminal?
Negative terminal = Left arm
Positive terminal = Left leg
38
Which lead can be used as the determinant of posterior vs anterior injury?
V2
39
In which precordial lead does the QRS complex have the most magnitude?
V4
40
What mV is denoted by a small box on an EKG strip?
0.1mV
41
What mV is denoted by a large box on an EKG strip?
0.5mV
42
What angle is viewed utilizing aVF?
90°
43
What angle is viewed utilizing aVL?
-30°
44
What angle is viewed utilizing aVR?
How does this compare to lead II?
-150°
- aVR is essentially opposite lead II. (not exactly though, Lead II's negative terminal is -120°)
45
What are the positive & negative terminals for lead aVR?
Negative = left arm + left leg (+30°)
Positive = right arm (-150°)
46
What are the positive & negative terminals for lead aVF?
Negative = left arm + right arm
Positive = left leg
47
What are the positive & negative terminals for lead aVL?
Negative = left leg + right arm
Positive = left arm
48
What cardiac EKG lead is the least useful in practice but most unique in its position? (this one has a lot of test questions about it)
aVR
49
What is the axis of Lead I?
0°
50
What is the axis of Lead III?
120°
51
What degree change would characterize an extreme axis deviation?
-90° to 180°
52
What would the mV of this QRS complex be?
+1.5mV
53
What would the mV of this QRS complex be?
- 1.0mV ( approximation)
54
Determine the mV of leads I & III and subsequently the degree & axis of deviation noted by these strips.
- Lead I ≈ -2.5mV
- Lead III ≈ +1.75mV
- Deviation ≈ inbetween +180° & +120° ≈ 170° due to greater Lead I magnitude. **Significant right axis deviation**
55
The EKG strips below are indicative of what pathology?
Right Bundle Branch Block (RBBB)
56
A notched, wide R wave on Lead V6 would likely be indicative of what condition?
- Left Bundle Branch Block (LBBB)
57
A positive current of injury noted on V2 would be indicative of what?
Posterior MI
58
A negative current of injury noted on V2 would be indicative of what?
Anterior MI
59
What axis would be expected with a negative QS deflection in leads I and II and a positive R deflection in Lead III?
Right Axis Deviation
60
What axis would be expected with a negative QS deflection in leads II and III and a positive R deflection in Lead I?
Left Axis Deviation
61
A positive V1 QRS with negative QRS in leads I, II, and III would the resulting axis be?
- Extreme Axis Deviation
62
What block would you expect to present with a right axis deviation?
- Posterior Hemiblock
63
What block would you expect to present with a left axis deviation?
- Anterior Hemiblock
64
What is an MCL1 lead?
How is it placed?
- Modified V1 lead
- Negative on left arm, positive in 4th ICS right of sternum.
65
What would leads I, III, and III look like with normal axis?
- All + QRS
66
Differentiate physiologic left axis and pathologic left axis deviation.
- Physiologic = (+ Lead I & - III) & (+ or isoelectric Lead II)
- Pathologic = (+ Lead I) & (- Lead II & III)
67
What is the most common cause of right ventricular hypertrophy?
- **Lung disease**, pulmonary embolus, and pulmonary valve disease.
68
In what situations would you find physiologic left axis deviation?
-( * hypertrophy ) Obesity & athleticism
69
Bundle Branch Block diagnosis is dependent on ______.
Hemiblock diagnosis is based on _______________.
- time
- axis deviation
70
What pertinent anatomical features of the heart are fed via the RCA?
- Inferior & posterior wall
- Right ventricle
- SA & AV node
- Posterior fascicle of LBB
71
What pertinent anatomical features of the heart are fed via the LAD?
- Anterior wall of LV
- Septal wall
- Bundle of His & BB
72
What severe outcome should you worry about with septal infarct?
Septal rupture
73
What pertinent anatomical features of the heart are fed via the circumflex artery?
- Lateral wall of LV
- *SA & AV nodes (?)
- Posterior wall of LV
*should be RCA, no?*
74
Why is morphine now avoided in MI's?
- Morphine causes histamine release.
75
What percentage occlusion would be assumed with chest pain on exertion?
70 - 85% occlusion
76
What percentage occlusion would be assumed with chest pain at rest?
90% occlusion
77
What percentage occlusion would be assumed with chest pain unrelieved by nitroglycerin?
100% occlusion
78
What should be administered before nitroglycerin with an acute right-sided MI?
fluid bolus
79
Are EKGs better in regards to sensitivity or specificity?
- Specificity (If MI is shown on EKG then its likely an MI) but sensitivity is 50% for EKGs so a negative EKG result doesn't rule out MI.
80
What sign would indicate ischemia?
- Symmetrical inverted T-waves in two or more related leads.
81
What sign would indicate an injury pattern?
- ST segment elevation of more than 1mm in two or more related leads.
*most important thing to look for*
82
What sign would indicate infarction?
- Pathologic Q waves ( >40ms wide or ⅓ the depth of r-wave height) coupled with ST elevation.
83
Which leads indicate a true lateral MI?
Which would indicate a high lateral?
- True lateral = V5 & V6
- High lateral = I, aVL
84
What is the most commonly seen MI?
What is commonly seen with this type of MI?
Do you use nitrates?
- Inferior
- Bradycardia, hypotension, 1st degree or Mobitz 1 blocks, and nausea.
- Caution with nitrates due to RV's being preload dependent w/ inferior MI's
85
What is the most lethal MI?
What dysrhythmias are commonly seen with this type of MI?
Do you use nitrates?
- Anterior Wall (LAD)
- CHB and VF/Vtach
- Yes to nitrates.
86
What would cause one to prepare defibrillation pads for a patient undergoing an anterior MI? (other than vfib/vtach)
- Presence of **BBB or hemiblock** whilst undergoing an anterior MI
87
What condition presents with ST elevation on all leads?
How is it diagnosed?
- Pericarditis
- Patient feels better when they lean forward and there won't be reciprocal ST depression.
- Diagnosed via fever, WBCs, hx of IVDU, etc.
88
What condition looks like myocardial infarction on an EKG but can be fatal if thrombolytics are administered?
- Dissecting thoracic aorta aneurysm.
89
What four conditions mimic myocardial infarction in their EKG presentation?
- LBBB
- LV hypertrophy
- Pericarditis
- Thoracic aortic dissection
