What is the paramedic treatment plan for a conscious adult patient with ventricular tachycardia (VT)?

Paramedic Treatment Plan for Conscious VT Patient

For a conscious (hemodynamically stable) adult patient with ventricular tachycardia, administer amiodarone 150 mg IV over 10 minutes as first-line pharmacologic therapy, with synchronized cardioversion as the immediate backup if the patient becomes unstable or medication fails. 1

Initial Assessment and Stabilization

Confirm the rhythm is truly VT and assess hemodynamic stability immediately. 2

• Look specifically for hypotension, altered mental status, signs of shock, chest pain, or acute heart failure symptoms 3, 2
• If any of these signs develop, the patient is unstable and requires immediate synchronized cardioversion (see below) 3, 4
• Establish IV access and prepare cardioversion equipment at bedside before administering any medications 5
• Obtain a 12-lead ECG if time permits, but do not delay treatment 6

Pharmacologic Management for Stable Conscious VT

Amiodarone is the first-line antiarrhythmic for stable VT in the prehospital setting. 3, 1

Amiodarone Dosing Protocol:

• Initial dose: 150 mg IV mixed in 100 mL D5W, infused over 10 minutes 1
• This can be repeated for breakthrough VT episodes 1
• After initial bolus, if transport time is prolonged, start maintenance infusion at 1 mg/min (360 mg over 6 hours) 1
• The FDA label specifically indicates amiodarone for hemodynamically unstable VT, but it is the standard antiarrhythmic used in prehospital settings for stable VT as well 1

Critical Administration Points:

• Use a volumetric infusion pump, not drop counters (which can underdose by up to 30%) 1
• Monitor for hypotension during infusion—this is the most common acute side effect 1
• For concentrations >2 mg/mL, use a central line if available; peripheral access is acceptable for short transport times at lower concentrations 1

Immediate Cardioversion Protocol

If the patient becomes unstable at any point or medication fails, perform immediate synchronized cardioversion. 3, 4

• Initial energy: 100 joules synchronized (standard for monomorphic VT) 3
• Ensure adequate sedation if the patient remains conscious (consider midazolam 2-5 mg IV or fentanyl 50-100 mcg IV if protocols allow) 3
• Have defibrillation capability ready in case VT degenerates to VF 5
• If standard cardioversion fails, consider double sequential cardioversion (two defibrillators simultaneously) for refractory VT 7

Critical Pitfalls to Avoid

Never administer calcium channel blockers (diltiazem, verapamil) or adenosine for wide-complex tachycardia. 3, 2, 5

• These agents are for SVT only and can cause cardiovascular collapse or ventricular fibrillation in VT patients 3, 2
• If there is any doubt whether the rhythm is VT versus SVT with aberrancy, treat as VT 2
• Do not delay cardioversion to establish IV access in an unstable patient 3

Post-Conversion Management

After successful conversion to sinus rhythm, start an amiodarone maintenance infusion to prevent recurrence. 1, 4

• Maintenance rate: 0.5 mg/min (720 mg over 24 hours) 1
• Continue infusion during transport to definitive care 1
• Monitor for atrial or ventricular premature complexes immediately after conversion 8
• Reassess hemodynamic stability continuously, as VT may recur 4

Transport Considerations

• Transport to a facility with cardiac catheterization and electrophysiology capabilities 9
• Continuous cardiac monitoring and pulse oximetry throughout transport 6
• Maintain IV access and keep cardioversion equipment immediately available 5
• Brief receiving facility about rhythm, interventions performed, and patient response 6