Cardiac Rhythm Analysis 2 Flashcards
(41 cards)
What are the features of ventricular rhythms?
1) WIDE QRS
Depolarization spreads abnormally along muscle cells and not proper conduction pathways
2) QRS, ST, T look BIZARRE
Conduction is abnormal, repolarization is also abnormal
What do abnormal ST and T waves indicate in ventricular rhythms?
Abnormal conduction, NOT ischemia or infarct
Premature Ventricular Complex: Criteria, types
Early beat, wide and bizarre QRS > 0.12 secs
Unifocal PVC
Multifocal PVC
R-on-T
(The R wave of the PVC falls on the preceding T wave)
Multiple PVCs in a row: 3 or more is a “run of V-Tach”. Paired PVC are “couplets”
Ventricular bigeminy/trigeminy (every 2nd/3rd beat is a PVC)
What is it called when you have more than 3 PVC in a row?
Run of v-tach
Premature Ventricular Complex: Etiology, physiology
Ectopic site in the ventricles, reduces stroke volume by 30-60% due to early depolarization, impaired ventricular contraction and loss of atrial kick
Hypokalemia, dilated ventricles (CHF), myocardial ischemia or infarct
Premature Ventricular Complex: Treatment
Do not require treatment if isolated, treat underlying cause.
If pt symptomatic with increasing PVCs, amio may be given esp if underlying rhythm has a lengthened QT interval
Idioventricular escape rhythm: Criteria, physiology, etiology
QRS wide and bizarre, HR 20-40
Both SA and AV node failed, ventricles initiate impulses to try and sustain life. No atrial activity, very low CO. EMERGENCY
Expected- dying pt
Unexpected- hyperkalemia, severe acid base imbalance
Idioventricular escape rhythm: Treatment
If withdrawing care, no treatment. Otherwise investigate why other pacemakers failed, epinephrine for CO, atropine tried to increase SA node activity, pacing
DO NOT ADMINISTER VENTRICULAR ANTIARRYTHMICS
Can we give amio for Idioventricular escape rhythm?
NO do not administer ventricular antiarrythmics
Accelerated idoventricular escape rhythm: Criteriam, etiology, physiology
QRS wide and bizarre, HR 40-100
Common reperfusion arrythmia, transient, seen after inferior MI with SA/AV node involvement
An ectopic site in ventricles fire at 40-60bpm. Irritable focus usually secondary to ischemia or infarct
Accelerated idoventricular escape rhythm: Treatment
Give O2 if required to reperfuse cardiac tissue. In-between rhythm is hard to treat, usually self-limiting. If sustained HR is LOW and the pt becomes SYMPTOMATIC, then atropine may be trialed to increase SA function
Meds that speed up rhythm may cause more dangerous ventricular arrythmias, ventricular antiarrythmics may further slow down rhythm
Ventricular Tachycardia: Criteria, etiology
QRS wide and bizarre, monomorphic (uniform QRS), polymorphic (QRS shape varies)
Myocardial infarct or ischemia, electrolyte imbalance, acid base imbalance, anything that causes long QT
Ventricular Tachycardia: Physiology
Ectopic sites in the ventricles fire at fast rate, taking over pacemaker functioning. Treatment focuses on suppressing irritable ectopic site.
Torsades de Pointes: Etiology
Meds that lengthen QT interval (Haldol), electrolyte imbalances (hypo-mg, hypo-K)
Ventricular tachycardia: Treatment
Assess pt if stable, unstable, or pulseless
1) Stable (BP normal, pulse strong)
12 lead ECG and consider adenosine if monomorphic and regular for diagnostic purposes
Give antiarrhythmics (amiodarone)!!!
2) Unstable (BP dropping, pulse weak, symptomatic)
Synchronized cardioversion
3) Pulseless (No BP, no pulse)
Defibrillate immediately 120-200J
Continuous CPR with drugs administered during CPR
MD may defibrillate again as needed during session
Epi every 3-5 mins
Amio may be given
Ventricular fibrillation: Criteria, etiology, physiology
Chaotic irregular deflections, no pattern
Myocardial infarction, electrolyte imbalance, acid base imbalance, anything that causes long QT
Ectopic site in the ventricles fire but is not organized or uniform
Ventricular fibrillation: Treatment
Defibrillate immediately 120-200J,
Continuous CPR with drugs administered during CPR
Epi every 3-5 mins
MD may defibrillate again as needed during session
Amio may be given
Asystole: Criteria, etiology, physiology
Flat or wavy line, MAY HAVE P WAVES
Myocardial infarction, hypothermia, massive pulmonary embolism, cardiac tamponade
No electrical activity
Asystole: Treatment
Confirm tracing and leads
CPR
Epinephrine
DO ABOVE WHILE DETERMINING CAUSE
DEFIBRILLATION NOT APPROPRIATE BECAUSE NOTHING TO SHOCK
Pulseless electrical activity (PEA): Criteria, physiology
Electrical activity (excluding VT and VF) with no pulse
Heart has some electrical conduction functioning but little or no contractility and cannot generate cardiac output. May be due to severe hypovolemia due to loss of preload
PEA: Treatment
Prognosis is poor, initiate fluid bolus, investigate other causes while CPR and epinephrine
PEA: Etiologies and most common cause
Loss of preload and severe hypovolemia most common cause
Hypoxia, hypo/hyperthermia, tension pneumothorax, cardiac tamponade
What are the features of junctional rhythms?
Originate in the AV node, and conduction goes down to the ventricles or retrograde up to the SA node therefore resulting in different conduction patterns where P is inverted or absent prior to a narrow QRS:
Absent P before QRS (impulses originate in AV and conduct down to the ventricles. No atrial conduction)
Inverted P before QRS (Conduction first travels retrograde up to the SA node resulting in inverted P wave, then conduct down to ventricles)
Inverted P after QRS (Conduction first goes to ventricles then retrograde up to SA node)
Inverted P during QRS (Conduction goes down to ventricles and retrograde up to SA node at about the same time resulting in inverted P superimposed in the QRS. will make QRS look slightly wide)
Premature Junctional Complex: Criteria, etiology, physiology, treatment
Early beat with inverted or absent P prior to a narrow QRS
Inferior wall MI (affecting SA, AV node), congestive heart failure, electrolyte imbalance
Ectopic focus in the AV junction fires before SA node discharges next impulse
Treatment: Usually none other than to investigate cause
