FIELD REFERENCE
Full criteria & treatment guidance
Key cautions & base contact
- Do not administer adenosine to a wide, irregular rhythm.
- A regular narrow rhythm does not by itself prove a primary arrhythmia; assess suspected hypovolemia and stability first.
Confirm the rhythm & assess perfusion
- This adult order applies to a regular rhythm above 100/min with QRS width below 0.12 seconds. Record a rhythm strip.
- Assess BP, consciousness, chest symptoms, oxygenation, and evidence of hypovolemia. Provide oxygen when room-air SpO₂ is below 95%.
Address suspected volume depletion
- For suspected hypovolemia with clear lungs/no CHF, give 250 mL normal saline, repeating up to 1 L to maintain perfusion.
- Reassess lung sounds; stop fluid infusion if rales develop. This assessment applies to both the 100–150 range and the faster-rate pathway.
Rate at least 150: choose the branch
- With mild chest discomfort, lightheadedness, or diaphoresis: attempt Valsalva. If the regular narrow-complex rhythm persists, give adenosine 12 mg rapid IV; may repeat once after 3 minutes.
- With cardiac chest discomfort, altered mental status, or systolic BP below 90: synchronized cardioversion at 100 J initially, then once at maximum energy if needed, or use the manufacturer’s recommended settings.
Reassess & transport
- Document conversion or persistent rhythm and reassess BP, consciousness, chest symptoms, and perfusion. Provide ALS escort to the nearest ERC or contact base as needed.
- A regular rate near 150 may represent flutter and may not respond to adenosine. An unstable patient may require immediate cardioversion without premedication; if synchronization fails, unsynchronized treatment may be needed.
VISUAL FIELD REFERENCE
Regular narrow rhythm at ≥150/min: choose the branch
Adult / adolescent · ALS
Assess rhythm, perfusion, and possible hypovolemia first. The full order also addresses rates of 100–150/min.
Mild symptoms
With mild chest discomfort, lightheadedness, or diaphoresis: attempt Valsalva. If the regular narrow-complex rhythm persists, give adenosine 12 mg rapid IV; may repeat once after 3 minutes.
Cardiac chest discomfort, altered status, or SBP <90
With cardiac chest discomfort, altered mental status, or systolic BP below 90: synchronized cardioversion at 100 J initially, then once at maximum energy if needed, or use the manufacturer’s recommended settings.
- Do not administer adenosine to a wide, irregular rhythm.
- For suspected hypovolemia with clear lungs/no CHF, give 250 mL normal saline, repeating up to 1 L to maintain perfusion.
Selected checkpoints; read the complete guide for criteria, exclusions, doses, and ongoing care. SO-C-025
UNDERSTAND THE CARE
Why rhythm classification and stability are separate decisions
A regular narrow rhythm identifies an electrical pattern, not the reason the rate is fast. The local order first considers perfusion and possible volume depletion. A fast compensatory response and a primary rhythm problem need to be distinguished through the complete presentation rather than rate alone.
Applying the guidance
Once the correct rate and symptom branch is established, prepare the selected intervention and reassess rhythm and circulation afterward. Document conversion or persistence, the pressure and the patient’s symptoms. Adenosine may help reveal atrial activity without resolving the underlying rhythm, so a monitor change should be described rather than overinterpreted.
Putting it together
Teaching example: the monitor rate is unchanged after an intervention but the patient becomes confused with worsening pressure. Reclassify stability from the current patient findings and use the appropriate escalation branch.
Diagram text & teaching checkpoints
- Rhythm
- Regular, narrow and correct rate range.
- Cause and perfusion
- Assess volume depletion and symptoms.
- Branch choice
- Mild symptoms versus instability.
- Response
- Document rhythm AND circulation.
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.