Tachycardia resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: M.Umer Tariq [2]; Priyamvada Singh, M.D. [3]

Tachycardia resident survival guide Microchapters
Overview
Classification
Causes
FIRE
Diagnosis
Treatment
Do's
Dont's

Overview

Tachycardia is a form of cardiac arrhythmia which refers to a rapid beating of the heart. By convention the term refers to heart rates greater than 100 beats per minute in the adult patient. Heart rate typically greater than 150 beats per minute in tachyarrhythmia.

Classification

Tachycardia

Narrow complex tachycardia (SVT)

Wide complex tachycardia

The origin of the impulse: Atria

The origin of the impulse: AV junction

The origin of the impulse: Atria or AV junction

The origin of the impulse: AV junction

The origin of the impulse: Atria, AV junction or ventricles Presence of an accessory pathway

The origin of the impulse: Pacemaker

Atrial fibrillation Atrial flutter Ectopic atrial rhythm Multifocal atrial tachycardia (MAT) Paroxysmal atrial tachycardia (PAT) with block Premature atrial contractions (PAC) Sinus tachycardia Wandering atrial pacemaker Sick sinus syndrome

AVNRT AVRT (accessory pathway): - Wolff-Parkinson-White syndrome (WPW) - Lown-Ganong-Levine syndrome (LGL)

Accelerated junctional rhythm

SVTAC (SVT with aberrant conduction): Left bundle branch block Left anterior hemi-block Lefo posterior hemi-block Right bundle branch block Trifascicular block

Ventricular tachycardia Ventricular fibrillation Ventricular parasystole

Wolff-Parkinson-White syndrome (WPW) Lown-Ganong-Levine syndrome (LGL)

Pacemaker-mediated tachycardia Runaway pacemaker syndrome Sensor induced tachycardia

Algorithm based on the 2003 ACLS guidelines for the management of tachycardia.

Causes

Acute treatable causes of tachycardia

H's

• Hypoxia
• Hypovolemia
• Hydrogen ion (acidosis)
• Hypo-/hyperkalemia
• Hypothermia

T's

• Toxins
• Tamponade (cardiac)
• Tension pneumothorax
• Thrombosis, pulmonary
• Thrombosis, coronary

FIRE: Focused Initial Rapid Evaluation

A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients in need of immediate intervention.

Tachycardia

Pulse

No Pulse

Evaluate and treat instability:

Pulseless VT or PEA

❑  12-lead ECG, don't delay therapy ❑  IV/IO access ❑  Check Ventilation ❑  Supplementary oxygen if hypoxemic ❑  Check heart rate and blood pressure ❑  Check signs of end-organ hypoperfusion ❑  Altered mental status ❑  Cold extremities ❑  Cyanosis ❑  Oliguria (urine output <0.5 mL/kg/h) ❑  Sustained hypotension (≥30 min) ❑  SBP <90 mm Hg or ❑  MAP ↓ >30 mm Hg below baseline ❑  Ischemic chest discomfort ❑  Acute heart failure

Proceed to ACLS Cardiac Arrest Algorithm

Hemodynamic stable

Hemodynamic unstable

Check QRS-duration

Synchronized cardioversion: Consider sedation If regular narrow complex, consider adenosine

Wide complex tachycardia (≥120 ms)

Narrow complex tachycardia (<120 ms)

❑  Doses/details of synchronized cardioversion: ❑  Narrow regular: 50-100 Joule ❑  Narrow irregular: 120-200 Joule biphasic or 200 Joule monophasic ❑  Wide regular 100 Joule ❑  Wide irregular: defibrillation dose (Not synchronized) ❑  Adenosine IV dose: ❑  First dose: 6mg rapid IV push; follow with NS flush ❑  Second dose: 12mg if required

Consider expert consultation Consider antiarrhythmic infusion Consider adenosine only if monomorphic and regular

Vagal maneuvers (No carotic sinus massage in patients with recent transient ischemic attack/stroke/ipsilateral significant carotid artery stenosis/carotid artery bruit) Beta-Blockers or calcium channel blocker Consider expert consultation Adenosine if regular

Proceed to Hemodynamic instability resident survival guide

❑  Antiarrhythmic infusion for stable wide-QRS tachycardia: ❑  Procainamide IV Dose: ❑  20-50mg/min until: ❑  Arrhythmia suppressed ❑  Hypotension ensues ❑  QRS duration increases 50% ❑  Maximum dose 17mg/kg given. ❑  Maintenance infusion: 1-4 mg/min. ❑  Avoid if prolonged QT or CHF. ❑  Amiodarone IV Dose: ❑  First dose: 150mg over 10 minutes. Repeat as needed if VT recurs. ❑  Follow by maintenance infusion by 1mg/min for first 6 hours. ❑  Sotalol IV Dose: ❑  100mg (1.5mg/kg) over 5 minutes. ❑  Avoid if prolonged QT.

Proceed to Narrow complex tachycardia resident survival guide

Proceed to Wide complex tachycardia resident survival guide

Algorithm based on the 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care.

References