Procainamide: Difference between revisions

Revision as of 05:09, 25 August 2013

Mechanism of Action

Class Ia
- Binds to fast sodium channels in inactive state inhibiting recovery after repolarization
- Prolongs action potential and reduces speed of impulse conduction
  - Depresses myocardial conduction
- May act as negative inotrope, causing hypotension through peripheral vasodilation

Adult Dosing

20 - 50 mg/min intravenously over 25 - 30 minutes
Give until:
- arrhythmia is suppressed
- patient develops hypotension
- QRS segment prolongs by >50% of baseline
- maximum dose of 17mg/kg is given
If effective, start continuous infusion at 1-4 mg/min
- Continuous infusion has fewer adverse effects than bolus

Indications

Wide-complex tachycardia of unknown type (in patient with preserved left ventricular function)
Stable ventricular tachycardia

Contraindications

Not recommended for ventricular fibrillation or pulseless ventricular tachycardia, as it takes too long to dose
2nd or 3rd atrioventricular block
Severe glycoside intoxication
Prolonged QT segment
Myasthenia gravis

Adverse Drug Reactions

Myocardial depression
Watch for QRS/QT segment prolongation, ventricular tachycardia, ventricular fibrillation, complete atrioventricular block, torsades de pointes

Kinetics

Onset of action: 5 - 10 minutes

@@ Line 1: / Line 1: @@
+== Mechanism of Action ==
+*Class Ia
+**Binds to fast sodium channels in inactive state inhibiting recovery after repolarization
+**Prolongs action potential and reduces speed of impulse conduction
+***Depresses myocardial conduction
+**May act as negative inotrope, causing hypotension through peripheral vasodilation
 == Adult Dosing ==
-*Continuous infusion rate has fewer adverse effects
+*20 - 50 mg/min intravenously over 25 - 30 minutes
-**20-50mg/min for 25-30min
+*Give until:
-***Cont until arrhythmia is suppressed, hypotension, QRS >50% or max dose (17mg/kg)
+**arrhythmia is suppressed
-***If effective start cont infusion of 1-4mg/min
+**patient develops hypotension
+**QRS segment prolongs by >50% of baseline
+**maximum dose of 17mg/kg is given
+*If effective, start continuous infusion at 1-4 mg/min
+**Continuous infusion has fewer adverse effects than bolus
+== Indications ==
+*Wide-complex tachycardia of unknown type (in patient with preserved left ventricular function)
+*Stable ventricular tachycardia
 == Contraindications ==
-*Not recommended for V-fib or pulseless V-tach (too long to dose)
+*Not recommended for ventricular fibrillation or pulseless ventricular tachycardia, as it takes too long to dose
-*2nd or 3rd AV block
+*2nd or 3rd atrioventricular block
 *Severe glycoside intoxication
-*Prolonged QT
+*Prolonged QT segment
 *Myasthenia gravis
-== Indications ==
+== Adverse Drug Reactions ==
-*Wide-complex tachycardia of unknown type (in pts w/ preserved LV function)
-*Stable V-tach
-== Mechanism of Action ==
-*Class Ia
-**Binds to fast Na channels in inactive state thereby inhibiting recovery after repolarization
-**Prolongs action potential and reduces speed of impulse conduction
-***Depresses myocardial conduction
-**May act as negative inotrope, cause hypotension (peripheral vasodilation)
-== Adverse Drug Rxns ==
 *Myocardial depression
-*Watch for QRS/QT prolongation, V-tach, Vfib, complete AV block, torsades
+*Watch for QRS/QT segment prolongation, ventricular tachycardia, ventricular fibrillation, complete atrioventricular block, torsades de pointes
 == Kinetics ==
-*Onset of action = 5-10min
+*Onset of action: 5 - 10 minutes
 ==See Also==