JUNCTIONAL DYSRYTHMIAS Flashcards
PREMATURE JUNCTIONAL CONTRACTIONS (PJCs) (EKG CHARACTERISTICS)
P wave: No upright P waves in Lead II, therefore there are no true P waves. (May or may not be present in other leads, NOT LEAD II. If present, it is inverted {retrograde} and may precede or follow the QRS)
PRI: For this class, there are NO PR intervals for junctional complexes, even if there is an inverted P wave before the QRS.
QRS: 0.08-0.12 seconds (not wide and bizarre {PVCs})
RATE: 6 second method; atrial and ventricular rates are determined by the underlying rhythm.
RHYTHM: Atrial: Upright P waves (if present) in the underlying rhythm, would be irregular because of the PJCs. Ventricular rhythm = irregular because of the PJCs.
PREMATURE JUNCTION COMPLEX (COMMON CAUSES) {6}
Hypokalemia
Hypomagnesemia
Hypoxia
Caffeine
ETOH
Medication (sympathomimetics){epinephrine}
PJCs Nursing Interventions {4}
Palpate pulse
Chronic or new onset?
Assess for cause
Trend
PJCs Treatment and Risks
Treatment:
Treat possible cause {6 causes}
Risks:
Patients at higher risk for junctional
dysrhythmias (and loss of cardiac
output)
Junctional Escape Beats/Rhythms
(INFORMATION)
A junctional escape beat originates in the AV junction and appears late (after the next expected sinus beat)
A junctional escape beat is PROTECTIVE- preventing cardiac standstill
A junctional escape RHYTHM is 3 or more sequential junctional escape beats
Junctional escape beats and rhythms occur when the SA node fails to pace the heart or AV conduction fails. Junctional escape rhythms occur at a very regular rate of 40 to 60 beats per minute.
JUNCTIONAL ESCAPE RHYTHM
(EKG CHARACTERISTICS)
P wave: No upright P waves in Lead II, therefore there are no true P waves
PRI: For this class, there are NO PRIs for junctional complexes, even if there is an inverted P wave before the QRS
QRS: .08-.12 Seconds
RATE: NO atrial rate because there are NO UPRIGHT P waves.
Ventricular rate is 40 – 60 bpm
RHYTHM: NO atrial rhythm because there are NO upright P waves.
Ventricular rhythm is VERY regular (R-R COMPLEXES=REGULAR)
JUNCTIONAL ESCAPE BEATS
(EKG CHARACTERISTICS)
A junctional escape beat originates in the AV junction and appears LATE (after the next expected sinus beat)
-JEB= protective (preventing cardiac
standstill)
P wave: No upright P waves in Lead II, therefore there are no true P waves
PRI: For this class, there are NO PRIs for junctional complexes, even if there is an inverted P wave before the QRS
QRS: .08 - .12 Seconds
RATE: Measured w/ 6-second method to determine the # of JEB/minute
The atrial and ventricular rates are determined by the underlying rhythm.
RHYTHM: Upright P waves (if present) would be irregular because of the junctional escape beat.
Ventricular rhythm is IRREGULAR because of the junctional escape beat.
JUNCTIONAL ESCAPE RHYTHM
(NURSING INTEREVENTIONS)
[same intervention as BRADYCARDIA]
Nursing
Vital Signs (including SpO2)
Assess for shock (cool clammy skin,
ALOC)
Decrease HOB for hypotension
Oxygen if hypoxic
Assess for angina
IV access if symptomatic
12 Lead EKG (if new onset)
Identify and treat possible causes
(hold negative chronotropic
medications)
JUNCTIONAL ESCAPE RHYTHM
[PHARMACOLOGIC & ELECTRICAL INTERVENTIONS]
Pharmacologic
Atropine (initial dose is 0.5 mg IV) – if
symptomatic!
Electrical
Pacing – if overall ventricular rate is
slow and unresponsive to medication
ACCELERATED JUNCTIONAL RHYTHM (EKG CHARACTERISTICS)
- -An ectopic rhythm caused by*
- enhanced automaticity of the bundle*
- of His*
P wave: No upright P waves in Lead II, therefore there are no true P waves
PRI: For this class, there are NO PRIs for junctional complexes, even if there is an inverted P wave before the QRS
QRS: .08-.12 Seconds
RATE: NO atrial rate because there are NO UPRIGHT P waves.
Ventricular rate is 61-100 bpm
RHYTHM: NO atrial rhythm because there are NO upright P waves.
Ventricular rhythm is VERY regular (R-R COMPLEXES=REGULAR)
ACCELERATED JUNCTIONAL RHYTHM
(NURSING AND PHARMACOLOGIC INTERVENTIONS)
Nursing
Vital Signs (including SpO2)
Assess for shock (cool clammy skin,
ALOC)
Decrease HOB for hypotension
Oxygen if hypoxic
Assess for angina
IV access if symptomatic
12 Lead EKG (if new onset)
Identify and treat possible causes
(hold negative chronotropic
medications)
Pharmacologic:
Possible low dose dopamine IV infusion for BP support
(if symptomatic!!) [dopamine= positive inotropic agent]
JUNCTIONAL TACHYCARDIA
(EKG CHARACTERISTICS)
P wave: No upright P waves in Lead II, therefore there are no true P waves
PRI: For this class, there are NO PRIs for junctional complexes, even if there is an inverted P wave before the QRS
QRS: .08-.12 Seconds
RATE: NO atrial rate because there are NO UPRIGHT P waves.
Ventricular rate is 101 bpm OR greater
RHYTHM: NO atrial rhythm because there are NO upright P waves.
Ventricular rhythm is VERY regular (R-R COMPLEXES=REGULAR)
*Junctional tachycardia is three or more sequential premature junctional complexes occurring at a rate of more than 100/minute. Paroxysmal junctional tachycardia is a term used to describe a junctional tachycardia that starts and ends suddenly and is often precipitated by a premature junctional complex.
JUNCTIONAL TACHYCARDIA
(NURSING, PHARM, AND ELECTRICAL INTERVENTIONS) (9)
Nursing: (SVT interventions + identify and treat causes)
Vital Signs (including SpO2)
Assess for shock (cool clammy skin, ALOC)
Decrease HOB for hypotension
Oxygen if hypoxic
Assess for angina
IV access if symptomatic
12 Lead EKG
Identify and treat possible causes (Pain? Fever? Anxiety?)
Vagal Maneuvers (if rate > 160)
Pharmacologic:
Beta Blockers or Calcium Channel Blockers
Electrical:
NA for rates of 160 or less
