general approach: assess clinical condition – if below 50/min, treat for bradyarrhythmia
- identify and treat underlying cause: maintain airway, oxygen, monitor rhythm/BP/oximetry, IV accesss, 12 lead ECG if available
- assess stability: check for hypotension, altered mental status, signs of shock, ischemic chest discomfort, acute heart failure (SHIAH)
- if unstable, treat w/ atropine; if ineffective, give dopamine or epinephrine infusion à consider consultation or transvenous pacing

atropine: cholinergic antagonist, 0.5 mg IV every 3-5 minutes; max 3mg
- use w/ caution w/ acute coronary ischemia (increases cardiac demand)
- likely ineffective in patients who have had a cardiac transplantation
- avoid relying on use in 2^nd degree type II, or 3^rd degree AV block; use it, but don’t rely on it to be the only means because the vagus goes to the atria only (and not the ventricles, which are sympathetic)

if atropine doesn’t work, use dopamine or epinephrine @ 2-10µg/kg/min

transcutaneous pacing: temporary external pace, not mainstay treatment – external power source
- can be set as fixed or on-demand, rate of 30-180, current from 0-200mA, monitor blanking (prevents VG masking)
- best done w/ anterior/posterior placement, but also done like defibrillator
- electrical capture: inverted QRS, wide and inverted T-wave indicates a ventricular origin
- mechanical capture: palpate the right femoral artery to make sure the pace is the same as the electrical impulse à then raise power 10%; failure can be due to incorrect electrode placement, attachment issues, low current

NARROW COMPLEXES tachycardia

untreatable?

treatable?

NARROW COMPLEXES
untreatable, search for reversible causes: sinus tachycardia (SA node), atrial tachycardia (ectopic site in the atrium), multifocal atrial tachycardia (at least 3 ectopic sites), junctional tachycardia (AV node)
- all are due to increased automaticity, but no re-entry/conduction issue

treatable conditions: atrial fibrillation (lots of re-entry circles), atrial flutter (one re-entry loop), AV nodal reentry tachycardia, accessory pathway-mediated tachycardia (AVRT)

tachycardia treatable conditions: 4

treatable conditions: atrial fibrillation (lots of re-entry circles), atrial flutter (one re-entry loop), AV nodal reentry tachycardia, accessory pathway-mediated tachycardia (AVRT)

Tachycardia WIDE COMPLEXES 5

WIDE COMPLEXES
fast: VT and VF, SVT w/ aberrancy (BBB), AF w/ aberrancy, pre-excited tachycardia’s (AVRT/WPW, originating from before the bundle of his), ventricular paced rhythms

rx for wide QRS?

rx for normal QRS

wide QRS? if present, IV access and 12-lead ECG à adenosine only if monomorphic and regular, consider antiarrhythmics and consultation

normal QRS: IV access and 12-lead ECG à vagal maneuvers, adenosine if regular, beta blockers OR calcium channel blockers, consider consultation

·         PSVT (narrow complex) rx:

·         PSVT –vagal maneuvers

o   Vagal maneuvers will terminate 25% of PSVT

§  Valsalva for 15-30 secs

§  Carotid massage 5-10 secs up to 3 attempts

o   Adenosine in PSVT: 6 mg rapid IV push + 20 cc saline + raise the arm; second dose 12 mg

stable tachyarrhythmia w/ wide complex: 

stable tachyarrhythmia w/ wide complex: irregular (VF, polymorphic VT, AF w/ aberrancy, pre-excited AF) or regular (monomorphic VT, SVT w/ aberrancy, pre-excited SVT, ventricular paced rhythms)
- regular, stable VT (rare): shock or treat w/ procainamide (20-50mg/min), amiodarone (150mg over 10min), sotalol (100mg/min); can distinguish from SVT w/ aberrancy with adenosine (which will not treat stable VT, but will treat SVTs)
- polymorphic VT: immediate defib like VF; magnesium is used for this and torsades depointes VT w/ prolonged PR

unstable tachyarrhythmia: synchronized cardioversion at the QRS complex (not on T, can cause VF)
- AF> SVT>
- consider adenosine if there is a narrow complex