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Flashcards in EKG Deck (61)
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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
Q

Sinus Bradycardia (4)

A
  • 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
Q

Sinus Tachycardia (4)

A
  • 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
Q

Premature Atrial Contraction (PAC) (6)

A

: 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
Q

NSR (3)

A

: 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
Q

Sinus Tach

A

: 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
Q

Sinus brady (4)

A

: 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
Q

PAC

A
  • 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
Q

Atrial Flutter: saw tooth (5)

A
  • 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
Q

ATrial flutter (5)

A
  • 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
Q

Atrial Fibrilation: Irregularly Irregular (5)

A

: 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
Q

AFIB (6)

A
  • 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
Q

Left atrial appendige

A
  • site of clot formation in AFIb
  • watchman LAA closure device
  • traps it and breaks it up
37
Q

Nodal Junction Rhythm (5)

A

: 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
Q

Junctional rhythm (5)

A
  • 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
Q

cardiac dysrhythmias (6)

A
  • classified by severity, origin
  • goals of collaborative management include:
  • rapidly recognizing and treating
  • restoring cardiac rhythm
  • preventing sudden death
40
Q

Severity (14)

A
Pre-lethal
-PAC
-PVC
-Afib
-Aflutter
-Sinus tach
-Sinus arrythmia
-SSS
Lethal
-1st
-2nd
-3rd degree AV block
-Vtach
-vfib
-Idioventricular
-Asystole
41
Q

Origin (11)

A
ATrial
-PAC
-ATrial Flutter
-Afib
-Sinus Tach
-Sinus Arrhytmia
-Sinus brady
-SSS
Ventrcular
-PVC
-AV blocks 
-Vtach
-Vfib
42
Q

First Degree AV Heart Block (6)

A

: 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
Q

Heart Block 1

A

AV blocks

  • Also bundle branch blocks are a very different phenomenon
  • Tx: assess if they are taking dig, beta blockers, calcium channel blockers
44
Q

Second Degree Heart block Mobitz Type 1 (Wenkbach): Regularly Irregular (7)

A

: 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
Q

WEnkebach, 2nd degree, mobitz 1

A
  • 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
Q

Second degree Heart block Mobitz type 2: Regularly irregular (7)

A

: 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
Q

2nd degree, Mobitz 2

A

: 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
Q

3rd Degree Heart block, complete Heart Block (6)

A

: 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
Q

Complete heart block

A

: 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
Q

Premature VEntricular contraction (7)

A

: 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
Q

PVC

A

: 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
Q

Ventricular tachycardia (9)

A

: 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
Q

Vtach

A

Tx: patient is awake treat with lidocaine

-no pulse, CPR, defib

54
Q

ekg changes seen in MI (3)

A
  • T wave inversion: zone of ischemia
  • ST elevation: zone of injury
  • ABnomral Q: zone of necrosis
55
Q

Artery involvement (5)

A
  • 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
Q

VEntricular Fibrilation (6)

A

: 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
Q

Ventricular asystole

A

: absence of electrical activity

  • absence of ventricular electrical activity
  • no depolarization, no ventricular contraction
  • flat line
  • nothing, begin CPR
58
Q

Acute inferior wall MI (3)

A
  • Large Q wave
  • ST elevation
  • Inverted T wave
59
Q

TIPS

A
  • 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
Q

sinus arrhthymia (5)

A

: 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
Q

Sinus arrythmia

A

: 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