Critical Appraisal: The REASON Trial & Point-of-Care Ultrasound in Cardiac Arrest
Methodological critique of the REASON trial evaluating echocardiographic cardiac standstill, ROSC prediction, and pulse-check interruption hazards.
D
Dr. Elena Rostova, EM Research Lead
Emergency Medicine Contributor
• 2 min read
The REASON Trial (Resuscitation using Echocardiography Outcomes Network) remains one of the largest prospective multicenter observational studies evaluating point-of-care ultrasound (POCUS) during non-shockable cardiac arrest resuscitation in emergency departments.
1. PICO Framework Breakdown
| PICO Element | Clinical Trial Description |
|---|---|
| Population | 793 adult patients presenting with out-of-hospital or in-hospital non-shockable cardiac arrest (PEA / Asystole). |
| Intervention | Protocolized subxiphoid or parasternal cardiac POCUS performed during standard 10-second rhythm/pulse checks. |
| Comparator | Clinical resuscitation without ultrasound or comparing presence of cardiac motion vs. cardiac standstill. |
| Outcome | Primary: Return of Spontaneous Circulation (ROSC). Secondary: Survival to hospital admission & discharge. |
2. Key Biostatistical Findings
The presence of cardiac activity on initial POCUS was a powerful independent predictor of clinical outcomes:
- Cardiac Motion Present on Initial Echo:
- ROSC achieved in 50.9% of patients.
- Survival to hospital admission: 27.4%.
- Survival to hospital discharge: 3.8%.
- Cardiac Standstill (No Motion) on Initial Echo:
- ROSC achieved in only 14.3% of patients.
- Survival to hospital discharge: 0.6%.
Metric, Cardiac Motion, Cardiac Standstill, Relative Risk (RR), p-value
ROSC Rate, 50.9%, 14.3%, 3.56 (95% CI 2.8-4.5), < 0.001
Survival to Discharge, 3.8%, 0.6%, 6.33 (95% CI 1.4-28.6), 0.0043. Practical Emergency Department Translation
- Avoid Prolonging CPR Pauses: Always record a 5-second video clip during the pulse check and resume chest compressions immediately; analyze the loop while CPR is ongoing.
- Standstill is Not Absolute Termination: Standstill significantly reduces likelihood of ROSC (RR 0.28), but termination of resuscitation requires integrating overall clinical context (duration, ETCO2 < 10 mmHg, comorbidities).