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Cardiac arrest
Opioid OHCA outcomes similar to other arrests
Opioid-Associated vs Undifferentiated Out-of-Hospital Cardiac Arrest: Examining differences in outcomes and the relationship with Utstein variables
Resuscitation · 2026-10 · Added 11 October 2026
Analysis of 10,786 EMS-treated OHCAs in a Canadian registry found opioid-associated arrests had similar outcomes to undifferentiated arrests (OR 1.02), but Utstein variables like initial rhythm and witnessed status predicted outcome differently in the opioid group.
- Study type
- Registry
- Design
- Retrospective registry cohort with toxicological case classification
- Participants
- 10,786 EMS-treated OHCA (1,349 opioid-associated)
- Main finding
- No association between opioid-associated OHCA and favourable neurological outcome (OR 1.02, 95% CI 0.77–1.35), but significant interactions for sex (p=0.032), initial rhythm (p=0.024) and bystander-witnessed status (p<0.001)
- Caveat
- Opioid classification relied on post-mortem toxicology and death certificates, so misclassification is likely
- Bottom line
- Context only
Why it matters in Australia (High relevance). Opioid-toxicity arrests are a growing part of the Australian OHCA caseload and this is a large EMS-treated registry rather than an in-hospital cohort.
Learning goal
Understand how patient context in opioid-associated cardiac arrest shapes the prognostic value of Utstein variables.
More
- Topic: Cardiac arrest
- Daily scan: 11 October 2026
- Podcast: Paramedic Papers Daily, 11 October 2026
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