EKG: Interpretation Rhythms Flashcards
Each small box is equal to _____ seconds and there are _____ small boxes in each large box which represents to 0.20 seconds.
0.04; 5
The horizontal axis of an EKG strip represents _____ whereas the vertical axis represents _____
time (each small box = 0.04s); amplitude (each small box = 1 mV)
How many large boxes are in a 1 sec strip?
5
What does the P wave represent? And what is normal duration?
- Atrial depolarization
- < 0.12 second (< 3 small boxes)
The QRS complex represents the depolarization of _____ and the normal duration is _____.
ventricles; <0.12 second (< 3 small boxes)
What does the T wave represents?
Ventricular repolarization
Although not formally recognized in EKG interpretation, where would the atrial repolarization be?
Somewhere in the QRS
The PR interval stretches from the end of the P wave to the beginning of the _____ complex. What is that is the normal duration?
- QRS
- 0.12 - 0.20 second (3-5 small boxes)
What does the PR interval represent?
The time it takes to fire from the SA node to the AV node (slight delay) to start signaling the ventricles contract.
The QT interval from the the beginning of the QRS complex to the end of the _____ wave.
T
What does the QT interval represents the depolarization and repolarization of the _____.
ventricles
The ST segment represents the end of _____ depolarization. If it is elevated > _____ mV (2 small vertical boxes), then it is a problem i.e. myocardial injury.
ventricular; 2
The 5-step EKG interpretation method consists of the following steps:
1.) Is it regular aka equal spacing between each _____ complex?
2.) Determine the _____
3.) P to QRS Ratio (_____ : 1)
4.) Look at the PR interval
5.) Look at the QRS complex
- QRS
- Heart rate (HR)
- 1: 1
What are the 2 ways of determining whether there is equal spacing between each QRS complex? (To determine regularity of rhythm)
- “Marching” the spaces out w/ a piece of paper
- Count the # of small boxes in btwn
To determine the HR of an EKG strip, there are 2 ways.
1. 10-times Method: If you have a _____ second strip (30 big boxes), count the total # of QRS complexes and multiply by 10.
2. 1500 Method: (Only works for regular rhythm) Count the # of small boxes between two _____ complexes then divide by 1500.
- 6
- QRS
When doing Step 3 of the EKG interpretation method, you can are looking for one _____ wave for every QRS complex.
p
The PR interval should be _____ 0.12 - 0.20 sec (3-5 small boxes)
<
The QRS complex should NOT be wide and should only < 0.12 sec (3 small boxes). TRUE or FALSE.
TRUE
What is the only difference btwn normal sinus rhythm and bradycardia? V.s tachycardia?
Everything is the same except for the HR. Bradycardia is < 60 bpm and tachycardia is > 100 bpm.
The following are characteristics of normal sinus rhythm:
- Regular rhythm
- HR: _____
- 1 P wave for every QRS complex
- Normal PR intervals (<0.12-0.20 sec or 3-5 small boxes)
- All QRS complexes are narrow (<0.12 sec)
- 60-100 bpm
The following are characteristics of sinus arrhythmia:
- _____ rhythm
- HR: 60 - 100 bpm; vary w/ respiration
- 1 P wave for every QRS complex
- Normal PR intervals (< 0.12-0.20 sec or 3-5 small boxes)
- All QRS complexes are narrow (<0.12 sec)
Irregular; corresponding to the respiratory cycle
Sinus arrhythmias coincides w/ the _____ cycle.
respiratory
The following are characteristics of sinus bradycardia:
- Regular rhythm
- HR: _____ 60 bpm
- 1 P wave for every QRS complex
- Normal PR intervals (<0.12-0.20 sec or 3-5 small boxes)
- All QRS complexes are narrow (<0.12 sec)
<
If the pt is experiencing bradycardia but is asymptomatic, how would you intervene?
If pt is asymptomatic and vital signs are stable, just continue to monitor the pt.
What medications would you give to treat bradycardia while waiting for a pacemaker or if pacing is ineffective?
1.) Atropine (0.5 mg rapid infusion and can be repeated every 3-5 minutes up to a max of 3 mg total)
2.) If atropine is ineffective, give epinephrine infusion at a rate of 2-10 mcg/min.
3.) If low BP also, administer dopamine infusion at 2-10 mg/kg/min
The following are characteristics of sinus _____:
- Regular rhythm
- HR: > 100 bpm
- 1 P wave for every QRS complex
- Normal PR intervals (<0.12-0.20 sec or 3-5 small boxes)
- All QRS complexes are narrow (<0.12 sec)
tachycardia
In SA block, the SA node discharges impulses at regular intervals but some of these are delayed on their way to the _____.
atria
SA blocks are divided into three categories which are what?
- First-degree
- Second-degree (Type I and Type II)
- Third-degree
In second-degree type I block, the rhythm is irregular and the P-P interval get progressively _____ until an entire cycle (PQRST complex) is dropped (conduction time btwn the sinus node and the surrounding atrial tissue becomes progressively longer).
shorter
In second-degree type II block, the rhythm is _____ except for pauses (conduction time btwn the sinus node and atrial tissue is normal until an impulse is blocked, the duration of the pause is a multiple of the P-P interval), and an entire PQRST complex is missing .
regular
In third-degree block, the rhythm is regular except for pauses, and entire PQRST complex is missing and the pause (can last indefinitely period) ends w/ a sinus beat. TRUE or FALSE.
TRUE
The following are characteristics of _____ arrest:
- Rhythm: Regular, except for the missing PQRST complexes
- HR: 60-100 bpm
- P wave: Normal and constant when P wave is present; not measurable when P wave is absent
- QRS complex: Normal when present; absent during pause
sinus
The following characteristics of _____ _____ contractions (PACs)
- Rhythm: Irregular as a result of PACs
- P wave: Premature w/ an abnormal configuration; may be buried in previous T wave
- PR intervals: Usually normal (<0.12-0.20 sec or 3-5 small boxes); may be slightly shortened or prolonged
- QRS complexes: Similar to underlying QRS complex when PAC is conducted; may not follow the premature P wave when a nonconducted PAC occurs
premature atrial
The hallmark EKG characteristic of a PAC is a premature (early) P wave w/ an abnormal shape i.e. inside the preceding T wave. TRUE or FALSE.
TRUE
PACs may occur in _____ (every other beat is a PAC), trigeminy (every 3rd beat is a PAC), or couplets (_____ PACs in a row)
bigeminy; 2
The following are characteristics of atrial _____:
- Rhythm: Atrial– regular, irregular in MAT; ventricular– regular when the block is constant and irregular when it isn’t
- HR: Atrial – 3 or more successive ectopic atrial beats at a rate of 150-250 bpm
- P wave: A 1:1 ratio w/ QRS complex (unless a block is present); may not be discernible; may be hidden in previous ST segment or T wave; in MAT, at least 3 different P waves seen
- PR intervals: Sometimes not measurable; varies in MAT
- QRS complexes: Usually normal (< 0.12 sec)
tachycardia
The following are characteristics of atrial flutter:
- Rhythm: Atrial– regular; ventricular– depends on the AV conduction pattern
- HR: Atrial– 250-350 bpm; ventricular < atrial
- P wave: Abnormal _____-toothed
- Normal PR intervals unmeasurable
- QRS complexes: Usually normal (< 0.12); may be widened if flutter waves are buried in complex
Saw
Abnormal P waves that have a saw-toothed appearance is the hallmark characteristic of _____ _____.
atrial flutter
The following are characteristics of _____ fibrillation
- Rhythm: Irregularly irregular
- HR: Atrial > 400 impulses/min, unable to measure; ventricular– varies from 100-150 bpm but can be ↓ or ↑
- P wave: Absent, replaced by fibrillatory waves
- PR intervals: Indiscernible
atrial
“Quivering” waves instead of distinct P waves are a hallmark sign of atrial _____.
fibrillation
The following are characteristics of wandering _____:
- Rhythm: Irregular
- HR: Usually normal or < 60 bpm
- P wave: Change in size and shape; first P wave inverted, second upright (at least 3 P waves of different size and shape)
- PR intervals: Variable; usually < 0.20 sec
- QRS complexes: Usually normal; < 0.12 sec
pacemaker
The following are characteristics of premature _____ contraction (PJC):
- Rhythm: Irregular w/ PJC appearance
- HR: Varying w/ underlying rhythm
- P wave: Inverted; occurs before, during, or after QRS complex; may be absent
- PR intervals: < 0.12 sec or unmeasurable
- QRS complexes: Usually normal; < 0.12 sec
junctional
The following are characteristics of junctional _____ rhythm:
- Rhythm: Regular. If the escape rhythm is intermittent, it will begin after a pause in the underlying rhythm
- HR: 40-60 bpm
- P wave: Inverted in leads II, III, and aVF; can occur before, during, or after QRS complex
- PR intervals: < 0.12 sec if P wave comes before QRS complex
- QRS complexes: Normal; < 0.12 second
escape
The following are characteristics of _____ junctional rhythm:
- Rhythm: Regular
- HR: 60-100 bpm
- P wave: Inverted in leads II, III, and aVF (if present); occurs before, during, or after QRS complex
- PR intervals: Measurable only w/ P wave that comes before QRS complex; < 0.12 sec
- QRS complexes: Usually normal; < 0.12 sec
accelerated
The following are characteristics of junctional _____.
- Rhythm: Regular
- HR: 100 - 200 bpm
- P wave: Inverted in leads II, III, and aVF; location varies around QRS complex
- PR intervals: Shortened at < 0.12 sec or unmeasurable
- QRS complexes: Normal; < 0.12 sec
tachycardia
Ventricular arrhythmias share the following 3 characteristics:
1. QRS complex: Wide, > 0.12 sec
2. T wave and QRS complex deflect in opposite directions
3. P wave is _____
absent
The following are characteristics of premature _____ contraction:
- Rhythm: Irregular during PVC; underlying rhythm may be regular
- HR: Patterned after underlying rhythm
- P wave: Absent
- PR intervals: Unmeasurable
- QRS complexes: Wide >0.12 sec and bizarre
ventricular
The following are characteristics of _____ rhythms:
- Rhythm: Atrial– undetermined; ventricular – usually regular
- HR: Atrial– unmeasurable; ventricular– 20-40 bpm
- P wave: Absent
- PR intervals: Unmeasurable
- QRS complexes: Wide >0.12 sec and bizarre
idioventricular
The following are characteristics of _____ tachycardia:
- Rhythm: Atrial– can’t be determined; ventricular – regular or slightly irregular
- HR: Atrial– can’t be determined; ventricular–100-250 bpm
- P wave: Absent or hidden by QRS complex
- PR intervals: Unmeasurable
- QRS complexes: Wide >0.12 sec and bizarre
ventricular
The following are characteristics Torsades de pointes:
- Rhythm: Ventricular– _____
- HR: 150-250 bpm
- P wave: Absent
- PR intervals: Unmeasurable
- QRS complexes: Wide, > 0.12 sec; rotates around the baseline; deflection downward and upward for several beats
irregular
The following are characteristics of ventricular _____:
- Rhythm: Can’t be determined
- HR: Can’t be determined
- P wave: Can’t be determined
- PR intervals: Can’t be determined
- QRS complexes: Can’t be dtermined
fibrillation
What cardiac rhythm is characterized by ventricular standstill and cardiac arrest aka a nearly flat line?
Asystole
What cardiac rhythm is characterized by electrical activity that is present on EKG but heart muscle can’t contract?
Pulseless Electrical Activity
AV blocks result from an interruption in impulse conduction between the _____ and _____.
atria; ventricles
AV blocks typically have a usually normal atrial rate (60-100 bpm) w/ a _____ ventricular rate
slowed
The following are characteristics of _____ AV block:
- Rhythm: Regular
- P wave: Normal (< 0.12 sec)
- PR intervals: Consistent for each beat; > 0.20 sec
- QRS complexes: Normal (< 0.12 sec); occasionally widened because of bundle branch block
first-degree
The following are characteristics of _____ second-degree AV block also known as Mobitz type I block:
- Rhythm: Atrial– regular; ventricular– irregular
- HR: Atrial rates > ventricular rate
- P wave: Normal
- PR intervals: Gradually gets longer w/ each beat until P wave fails to conduct to the ventricles
- QRS complexes: Usually normal < 0.12 sec
Type 1
The following are characteristics Type II _____ AV block also known as Mobitz II block:
- Rhythm: Atrial– regular; ventricular– irregular if block is intermittent, regular if block is constant (i.e. 2:1 or 3:1)
- PR intervals: Constant for all conducted beats, may be prolonged in some cases
- QRS complexes: Usually wide > 0.12 sec
second-degree
The following are characteristics third-degree _____ block:
- Rhythm: Atrial– regular; ventricular– regular
- HR: Atrial rate > ventricular rate
- P wave: Normal (< 0.12 sec)
- PR intervals: Variations w/ no regularity; no relation btwn P waves and QRS complexes
- QRS complexes: Normal (junctional pacemaker) or wide and bizarre (ventricular pacemaker)
AV
