Acute cardiac care & resuscitationSecondary analysis
Resuscitation From Out-of-Hospital Cardiac Arrest: When Is EtCO 2 Reliably Associated With Return of Spontaneous Circulation (ROSC)?
- Secondary analysis of the Pragmatic Airway Resuscitation Trial (PART) cluster-randomised trial
- inverse probability of treatment weighting
- group-based trajectory modeling
Authors' conclusion
Depending on witness status and initial EtCO2, between 7 and 21 minutes of monitoring are needed to reliably differentiate upward from downward EtCO2 trajectories during OHCA resuscitation.
Study context
- Population
- OHCA patients with EtCO2 data in the Pragmatic Airway Resuscitation Trial, stratified by witness status and initial EtCO2452 witnessed, 716 unwitnessed
- Participants
- 1,168 patients
- Comparison
- Upward vs downward EtCO2 trajectory
- Primary endpoint
- Earliest minute when CIs for ROSC between upward vs downward EtCO2 trajectories no longer overlapped
Primary result
As reported in the abstract
Earliest minute of nonoverlapping CIs for ROSC, upward vs downward EtCO2 trajectory
Upward vs DownwardRelative risk (95% CI)
witnessed, low initial EtCO2: 8 minutes
3.06(1.49–6.71)
witnessed, moderate EtCO2: 12 minutes
1.95(1.23–3.48)
witnessed, high EtCO2: 21 minutes
2.12(1.30–3.73)
- Unwitnessed arrests: nonoverlapping CIs first observed at 7 minutes
- RR, 3.56; 95% CI, 1.53, 10.37
Further findings
Overall ROSC
- All
- 18.2%
- Witnessed
- 30.5%
- Unwitnessed
- 10.5%
Original publication
Resuscitation From Out-of-Hospital Cardiac Arrest: When Is EtCO 2 Reliably Associated With ROSC? Circulation. Published 18 May 2026. doi:10.1161/circulationaha.125.077980
Summarised from the published abstract; every number is checked against it