FIELD REFERENCE
Full criteria & treatment guidance
Key cautions & base contact
- Use synchronized cardioversion for the pulsed pathway and confirm synchronization before each shock.
- Do not substitute the 300 mg arrest amiodarone dose for this 150 mg slow-infusion pathway.
Assess and document
- Confirm a pulse, monitor rhythm, and obtain a rhythm strip or 12-lead. Assess BP, mental status, chest symptoms, and perfusion.
- If an implanted defibrillator fires at least twice in 15 minutes, contact base for possible CVRC destination. Provide oxygen when room-air SpO₂ is below 95%.
Stable patient
- The stable branch describes systolic BP above 90, appropriate mental status, and minimal chest discomfort. Monitor serial vital signs and provide ALS escort to the nearest ERC.
- The treatment guideline favors transport without cardioversion or pharmacologic treatment for stable wide-complex tachycardia. Continue looking for deterioration.
Unstable patient
- Systolic BP at or below 90, altered consciousness, chest pain, or poor perfusion activates the unstable branch. Synchronized cardioversion starts at 100 J biphasic or the manufacturer-recommended setting; do not delay for IV access if deteriorating.
- If unsuccessful, give amiodarone 150 mg slow IV/IO OR lidocaine 1 mg/kg IV/IO. After 2–3 minutes of infusion, persistent unstable tachycardia leads to synchronized full-output/manufacturer-setting cardioversion.
- If persistent, repeat amiodarone 150 mg slow IV/IO OR lidocaine 0.5 mg/kg IV/IO, followed after 2–3 minutes by the next synchronized cardioversion step if needed.
Reassess and transport
- Reassess pulse, rhythm, BP, consciousness, and perfusion after every intervention. Amiodarone can cause hypotension, especially if administered too rapidly.
- Provide ALS escort to the nearest ERC or contact base as needed. If the pulse is lost, switch immediately to the arrest pathway.
VISUAL FIELD REFERENCE
Wide-complex tachycardia: a pulse changes the pathway
Adult / adolescent · ALS
Confirm a pulse. Continue to the complete treatment and reassessment sequence below.
Stable
The stable branch describes systolic BP above 90, appropriate mental status, and minimal chest discomfort. Monitor serial vital signs and provide ALS escort to the nearest ERC.
The treatment guideline favors transport without cardioversion or pharmacologic treatment for stable wide-complex tachycardia. Continue looking for deterioration.
Unstable
Systolic BP at or below 90, altered consciousness, chest pain, or poor perfusion activates the unstable branch. Synchronized cardioversion starts at 100 J biphasic or the manufacturer-recommended setting; do not delay for IV access if deteriorating.
- Provide ALS escort to the nearest ERC or contact base as needed. If the pulse is lost, switch immediately to the arrest pathway.
- Do not substitute the 300 mg arrest amiodarone dose for this 150 mg slow-infusion pathway.
Selected checkpoints; read the complete guide for criteria, exclusions, doses, and ongoing care. SO-C-040
UNDERSTAND THE CARE
Why a pulse changes the entire treatment branch
The first distinction is whether the patient has a pulse. For a perfusing wide-complex rhythm, pressure, mental status, chest symptoms and skin perfusion determine the stable or unstable pathway. A wide tracing alone does not establish the need for the same intervention used in cardiac arrest.
Applying the guidance
The stable branch emphasizes monitoring and transport, while deterioration activates the synchronized-treatment sequence. Recheck synchronization before each shock and document the response in both rhythm and perfusion. Medication preparation must retain the slow-infusion instructions for the pulsed pathway. If the pulse is lost, explicitly announce the transition to arrest care.
Putting it together
Teaching example: a patient initially meets the stable branch but becomes altered with poor perfusion. Reassess the current state and change pathways rather than continuing a plan based on the first blood pressure.
Diagram text & teaching checkpoints
- Pulse
- Pulsed rhythm versus cardiac arrest.
- Stability
- Pressure, consciousness, symptoms and perfusion.
- Treatment
- Use the matching synchronized/medication branch.
- Transition
- Reassess pulse after every intervention.
Sources for this explanation
Original OCMedic teaching synthesis of the references below. Educational expansion updated ; this is not a new independent clinical-review date. Source-specific dates and limitations remain in the full guidance.
Make a change in stability explicit
A stable assessment is a description of the patient at that moment. Preserve the initial rhythm and vital signs, then compare them with symptoms, consciousness and perfusion during transport. If the patient deteriorates, announce the changed findings and the treatment branch now being used. The plan should not remain anchored to the first pressure reading.
A helpful verbal update is: the rhythm persists, the patient previously met the stable branch, and the current examination now shows the specific unstable finding. That makes the reason for synchronized treatment understandable. Record the synchronized attempt and the clinical response, then follow the order’s medication and repeat-cardioversion sequence if needed.
The pulse check remains a separate decision throughout. Loss of pulse changes the pathway to cardiac-arrest care; a continuing wide tracing alone does not establish that circulation persists. When handing over medication already prepared or administered, name the pulsed indication and slow administration instructions. This avoids carrying the arrest preparation into a patient who still has a pulse or mistaking an unused repeat allowance for an instruction to administer it.
Sources: SO-C-040