EKG Flashcards
(61 cards)
1
Q
EKG (6)
A
- measures electrical activity of heart during cardiac cycle
- detect abnormal cardiac rhythms (rhythm disturbances, elyte imbalances), measures cardiac electrical activity, dx myocardial ischemia, injury, infarction
2
Q
pacemaker cells (5)
A
- sa node, av node, bundle of his, purkinje fibers
- spontaneously generate action potentials
- vary rate in response to ANS
- action potentials are associated with opening of slow calcium ion channels
- almost no contractile elements
3
Q
types of EKG (3)
A
- standard 12 lead
- bedside monitoring 3 lead
- bedside monitoring 5 lead
4
Q
12 lead EKG (5)
A
- 12 different pts to view cardiac electrical activity
- 6 limb leads I, II, III, avR, avL, avF
- 6 precardial leads: V1, V2, V3, V4, V5, V6
- draw a line through leads I, II,III is Einthoven’s triangle
- voltage (amplitude) of QRS in leads I plus III= amplitude of lead II
5
Q
3 Lead EKG (3)
A
- RA: white
- LA: black
- LF (ground): green or red
6
Q
5 Lead EKG (5)
A
- RA: white
- LA: black
- RL: green
- LL: red
- Ground (LF): brown
7
Q
assessment (5)
A
- assess pt knowledge of procedure
- pt needs to be supine for entire procedure
- lie still w/o talking during procedure
- explain that shaving body hair where electrodes are placed is necessary
- privacy
8
Q
application of EKG (9)
A
-apply electrode paste and leads
-Chest:
V1: measures fourth intercostal space at right sternal border
V2: fourth intercostal space at left sternal border
V3: midway between 2 and 4
V4: fifth intercostal space at midclavicular line
V5: L anterior axillary line at same level as V4
V6: L midaxillary line at same level as v4
-Extremities: one on each extremity
-placed on the limb (forearm, ankles), or trunk (shoulder and groins), LL must be placed below the umbilicus
9
Q
nursing considerations (6)
A
- important to correctly identify correct location of ICS before placement
- dry moist skin or shave body hair to provide clear reading
- apply lead wires on first before attaching to pets
- if continuous is needed vs short period of time, consider Holter monitor
- doc date, time, significant findings
- always check pt first before reading the rhythm
10
Q
ANS influences on Ion flux (5)
A
Sympathetic
-NE, E stimulates receptors, leading to opening of NA/CA channels
-Cell depolarizes more quickly
Parasympathetic
-acetylcholine stimulates muscarinic receptors. leading to opening of K channels
-K leaks out and offsets sodium influx
-cell depolarizes more slowly
11
Q
normal firing rates
A
SA: 60-100
AV: 40-60
V: 15-20, 20-40
12
Q
EKG graph (3)
A
- each small sq: 0.04 sec
- big box (5x5 small boxes) = 0.2 sec
- each section/strip = 6 sec
13
Q
Calculate the HR (4)
A
- count the number of little boxes between 2 QRS complexes and divide that number into 1500
- 1500 little boxes in one minute
- 300 big boxes in one minute
- if you have an irregular rhythm, count the number of QRS complexes in a 6 sec EKG strip and multiply by 10
14
Q
check for rhythm (8)
A
-do the wave forms (p-p, QRS-QRS, T-T) come at regular intervals?
-is there a p wave preceding each QRS?
-is the PR interval within normal limits, what is the relationship (0.12 to 0.20 seconds)?
-is the QRS interval within normal limits? (0.06-0.11 sec, less than 3 small boxes)
~some books say 0.04-0.10
-if you notice an arrhythmia, is there a pattern to it?
-what is the QRS rate (fast or slow)?
-do QRS complex look normal and reg rhythm?
15
Q
Seconds/boxes
A
PR interval: 0.12-0.20, 3-5 sm boxes
QRS complex: 0.06-0.11, <3 sm boxes
16
Q
Lead I (3)
A
: measures the difference between the left arm and right arm
- Right is negative
- right to left
17
Q
Lead II (3)
A
: measures the difference between the left leg and the right arm
- RA to LF
- largest
18
Q
Lead III
A
: measures the difference between the left arm and the left leg
19
Q
avR: unipolar (2)
A
: measures the difference between the heart and the right arm
-negative direction
20
Q
avL: unipolar (2)
A
: measures the difference between the heart and the left arm
-positive direction
21
Q
avF: unipolar (2)
A
: measures the difference btw left arm and left leg
-positive direction
22
Q
V leads
A
- measure horizontally
- unipolar
23
Q
Normal EKG components (8)
A
- Pwave: atrial depolarization, contraction
- PR interval: from beg of P wave to beginning of QRS, normal is 0.12-0.20
- Qwave: first negative wave after P wave and before R
- Rwave: first positive wave after P wave
- Swave: negative wave after R wave
- QRS interval: ventricular depolarization, contraction, beg of Q wave to end of S wave, normal is 0.6-0.10
- QT interval: beg of Qwave to end of T wave
- Twave: ventricular repplarization
24
Q
Normal Sinus Rhythm (4)
A
- P wave for each QRS, 1:1
- PR interval is normal 0.12-0.2 sec (3-5 sm boxes)
- QRS looks normal width and regular rhythm
- QRS rate is between 60-100
25
Sinus Bradycardia (4)
- P wave for each QRS, 1:1
- PR interval is normal 0.12-0.2, to slightly prolonged
- QRS looks normal width and regular rhythm, to slightly prolonged
- QRS rate is less than 60
26
Sinus Tachycardia (4)
- P wave for each QRS, 1:1
- PR interval is normal 0.12-0.20, or slightly shortened
- QRS looks normal width and regular rhythm, to slightly shortened
- QRS rate is above 100-160
27
Premature Atrial Contraction (PAC) (6)
: irregular rhythm due to occasional or frequent early beats
- P wave for each QRS, 1:1 but P wave of early beat is slightly different than normal P and P, QRS, T comes early
- PR interval is normal, and varies with PAC
- QRS looks normal width and regular rhythm except for PAC (bc once the early ectopic p wave hits the av node the electrical path is the same for ventricular depolarization)
- QRS rate is dependent on sinus rate, usually 60-100
- Non compensatory pause following PAC, next normal beat does not come when it normally would have bc PAC disrupts normal established rhythm
28
NSR (3)
: rhythm represents the normal state with the SA node as the lead pacer.
- The intervals should all be consistent and within the normal range.
- This refers to the atrial rate
- NSR can occur with a ventricular escape rhythm or other ventricular abnormality if AV dissociation exists
29
Sinus Tach
: Can be caused by meds or by conditions that require increased CO, such as exercise, hypoxemia, hemorrhage, and acidosis
-Tx: monitor VS, BP, treat underlying condition
30
Sinus brady (4)
: Origin may be in the SA node or in an atrial pacemaker
- This rhythm can be caused by vagal stimulation leading to nodal slowing, or by meds such as beta blockers, and is found normally in some well conditioned athletes
- QRS complex, and PR and QT intervals may slightly widen as the rhythm slows below 60 bp
- HOwever, they will not widen past the upper threshold of the normal range for that interval
- for example, the PR interval may widen, but should not widen over the upper range of 0.2 sec
- Tx: Monitor VS, bp, if hypotensive, shocky, change in MS, consider atropine
31
PAC
- Occurs when some other pacemaker cell in the atria fires at a faster rate than that of the SA node
- Result is a complex that comes sooner than expected
- Notice that the premature beat resets the SA node and the pause after the PAC is not compensated
- Underlying rhythm is disturbed and does not proceed at the same pace
- Noncompensatory pause is less than twice the underlying normal P-P interval
- Tx: Monitor VS, bp
32
Atrial Flutter: saw tooth (5)
- No Pwave, Fwave, characteristic saw tooth pattern
- PR interval is variable
- QRS looks normal width and reg rhythm, unless AV block
- Atrial rate is commonly 250-350
- Ventricular rate commonly 125-175
33
ATrial flutter (5)
- P waves appear in a saw toothed pattern
- QRS rate is usually regular and the complexes appear at some multiple of the P-P interval
- Usual QRS response is 2:1 (2 p waves for each QRS complex)
- THis is an atrial flutter with 2:1 block (some of the P waves are blocked and do not cause any ventricular response)
- Ventricular response can also occur at slower rates 3:1, 4:1, or higher
- Sometimes ventricular response will be irregular
- Occur at some multiple of P-P interval
- rate of intervals can vary, with some occurring at a rate of 2:1 and 3:1 block
- Ventricular response that does not fall on a mulitple of P-P interval.
- Call this an atrial flutter with a variable ventricular response
- Saw tooth appearance may bot be obvious in all 12 leads
- ventricular rate of 150, look for buried P waves of an atrial flutter with 2:1 block
- Tx: Monitor VS, bp, if ventricular rate is rapid consider cardioversion, dig, beta blockers, ca channel blockers, amiodarone
34
Atrial Fibrilation: Irregularly Irregular (5)
: No atrial contraction
: most common dysrhythmia and may lead to clot emboli and stroke
-No Pwave, chaotic atrial activity, small, squiggly, too small to count
-No PR interval
-QRS looks normal width but not at regular rhythm
-Rate is variable, ventricular rate is 100-160 ant R-R is always irregular
35
AFIB (6)
- Chatoic firing of numerous pacemaker cells in the atria in a totally haphazard fashion.
- REsult is no discernible p waves, and QRS are innervated haphazardly in irregular pattern
- Ventricular rate is guided by occasional activation from one of pacemaking sources
- Because ventricles are not placed by any one site, intervals are completely random
- Tx: monitor vs, bp, cardioversion, dig, beta blockers, ca channel blockers, amiodarone, anticoagulation to dec incidence of stroke
36
Left atrial appendige
- site of clot formation in AFIb
- watchman LAA closure device
- traps it and breaks it up
37
Nodal Junction Rhythm (5)
: impulse initiates from AV node junction between atria and ventricles
- No P wave (none, antegrade, retrograde-1:1)
- No PR interval, short, or retrograde (does not represent atrial stimulation of the ventricles)
- QRS and T look normal width, and regular rhythm
- rate is 40-60 bpm
38
Junctional rhythm (5)
- ARises as an escape rhythm when normal pacemaking fn of atria and SA node is absent.
- Can also occur inc as of AV dissociation or third degree AV block
- Tx: monitor VS, bp, treat underlying cause-MI, CHF, acidosis, hyperkalemia
39
cardiac dysrhythmias (6)
- classified by severity, origin
- goals of collaborative management include:
- rapidly recognizing and treating
- restoring cardiac rhythm
- preventing sudden death
40
Severity (14)
```
Pre-lethal
-PAC
-PVC
-Afib
-Aflutter
-Sinus tach
-Sinus arrythmia
-SSS
Lethal
-1st
-2nd
-3rd degree AV block
-Vtach
-vfib
-Idioventricular
-Asystole
```
41
Origin (11)
```
ATrial
-PAC
-ATrial Flutter
-Afib
-Sinus Tach
-Sinus Arrhytmia
-Sinus brady
-SSS
Ventrcular
-PVC
-AV blocks
-Vtach
-Vfib
```
42
First Degree AV Heart Block (6)
: delay or interruption in conduction btn atrial and ventricles
- monitor for effects of drugs like Dig and dec K
- P wave occurs with each QRS, 1:1
- PR interval is prolonged > 0.20 sec
- QRS is normal looking width, reg rhythm
- rate depends on sinus rhythm, 60-100
43
Heart Block 1
AV blocks
- Also bundle branch blocks are a very different phenomenon
- Tx: assess if they are taking dig, beta blockers, calcium channel blockers
44
Second Degree Heart block Mobitz Type 1 (Wenkbach): Regularly Irregular (7)
: block occurs at level of av node
- P wave is present for each QRS, 2:1, 3:2, 4:3, 5:4
- PR interval is variable, progressive prolongation until a beat/QRS is dropped and then rhythm repeats itself
- QRS is normal looking width, but irregular rhythm
- Grouping is present and variable
- Dropped beats
45
WEnkebach, 2nd degree, mobitz 1
- CAused by diseased AV node with a long refractory period
- Result is that the PR interval lengthens between successive beats until a beat is dropped
- AT that point the cycle starts again
- The R-R interval shortens with each beat
- Tx: monitor vs, bp, tx is rarely required unless bradycardia
46
Second degree Heart block Mobitz type 2: Regularly irregular (7)
: more serious, block occurs in AV node at bundle of HIS or bundle branches, impulse is blocked
- Pwave present but not have corresponding QRS, X:x-1, 3:2, 4:3, 5:4, or variable on rare occasions
- PR interval is normal and constant
- QRS either normal width or wide
- Rate is slow and less than atrial rate, 30-100
- Grouping is present and variable
- Dropped beats
47
2nd degree, Mobitz 2
: Grouped beats with one beat dropped between each group
- Pr interval is the same in all of the conducted beats
- CAused by a diseased AV node, and is an ominous sign for complete heart block
- Tx: monitor vs, bp, tx is required if bradycardia, symptomatic may require a pacemaker
48
3rd Degree Heart block, complete Heart Block (6)
: no conduction between atria and ventricles
- P wave is present but doesn't have a QRS with each one
- PR interval is variable, no pattern, relationship
- QRS normal or wide looking
- RAte is slower than atrial rate, separate rates for underlying sinus rhythm and escape rhythm because they are dissociated from one another
- P wave is 60-100, QRS 20-40
- pt needs pacemaker
49
Complete heart block
: Complete block of av node
- atria and ventricles are firing separately each to its own drummer
- Sinus rhythm can be bradycardic, normal, or tachycardic
- Escape beat can be junctional or ventricular and their morphology will vary
50
Premature VEntricular contraction (7)
: rhythm is irregular to occasional or frequent PVC
- No P wave before the PVC
- PR interval is absent
- QRS is prolonged, wide and bizarre,
- Rate depends on underlying rhythm
- PVC followed by a full Compensatory pause (next normal beat following PVC comes right on time as if there were no irregularity to rhythm
- multifocal PVC are more serious than unifocal PVC bc more than one irritable ventricular focus
51
PVC
: Caused by premature firing of a ventricular cell
- Ventricular pacer fires before the normal SA node or supra ventricular pacer, which causes the vetricles to be in a refractory state (not yet depolarized and unavailable to fire again) when normal pacer fires
- Ventricles do not contract at their normal time
- Underlying pacing schedule is not altered, so beat following the PVC will arrive on time
- Called a compensatory pause
52
Ventricular tachycardia (9)
: no normal looking QRS but rhythm is regular
- No P wave
- No PR interval
- QRS complex is greater than0.12 sec, wide undulating waves
- Rate is 100-250 bpm
- more than 3 PVC in a row called vtach
- synchronize defib (cardioversion)
- does not always lead to Vfib
- deadly rhythm
53
Vtach
Tx: patient is awake treat with lidocaine
| -no pulse, CPR, defib
54
ekg changes seen in MI (3)
- T wave inversion: zone of ischemia
- ST elevation: zone of injury
- ABnomral Q: zone of necrosis
55
Artery involvement (5)
- Lateral wall infarct (I, avL, V5, V6)
- Inferior wall infarct (II, III, avF), posterior descending branch of RCA
- Septal infarct (V1, V2), septal branch of LAD
- Anterior wall infarct (V3, V4), LAD
- Posterior wall infarct (reciprocal chg in V1-V4), left circumflex
56
VEntricular Fibrilation (6)
: emergency, defib
- No P wave
- No PR interval
- No normal looking QRS complexes, Irregular shape
- Rate is fast
- EKG looks like chicken scratch, chaotic
57
Ventricular asystole
: absence of electrical activity
- absence of ventricular electrical activity
- no depolarization, no ventricular contraction
- flat line
- nothing, begin CPR
58
Acute inferior wall MI (3)
- Large Q wave
- ST elevation
- Inverted T wave
59
TIPS
- look for keg changes of MI in groups of leads
- T waves: normally are positive except in avR, V1
- may initially increase in amplitude followed by inversion in an acute event
- ST segment changes: normally the segment is w/in 1 mm of isoelectric line
- st depression > 1mm =ischemia
- ST elevation >1mm=injury or infarct
- LBBB: new LBBB may be indicative of infarction
- Qwave: significant if at least 1/3 the size of R wave
- R wave progression: loss of R wave progression in the V leads indicative of anteroseptal infarct
- NSTEMI: results from a partially occluding thrombus
- characterized by ST depression, T wave inversion, or non specific ST elevations
- STemi results from total occlusion by a thrombus
60
sinus arrhthymia (5)
: varies with respiration
- P wave is normal, 1:1
- PR interval is normal
- QRS is normal looking with regular rhythm
- TP interval varies with respiration (inc on inspiration, dec on exhalation)
- Rate is normal sinus 60-100
61
Sinus arrythmia
: Represents normal respiratory variation, becoming slower during exhalation and faster upon inhalation
- Occurs because inhalation increases venous return by lowering intrathoracic pressure
- PR intervals ar teh same, only the TP intervals ( from end of the T wave of one complex to the beginning of the P wave of next complex) vary with respirations
