Lit Matters 1: Intracranial hemorrhage in OHCA

Intracranial hemorrhage is an uncommon but high-stakes cause of non-traumatic out-of-hospital cardiac arrest after ROSC. In a systematic review of roughly 50,000 patients, ICH appeared in 4.3% overall and carried markedly worse outcomes, making post-arrest head CT a real diagnostic and prognostic decision.

Head CT After ROSC

• Overall ICH prevalence: Systematic review data put intracranial hemorrhage at 4.3% of non-traumatic OHCA, enough to keep neurogenic arrest on the differential even when the post-ROSC workflow is pulling you toward ACS.
• Post-ROSC CT rationale: Early head CT can change both diagnosis and downstream treatment, especially before anticoagulation or thrombolytics, and that bedside pause about who should be scanned is worth hearing in the episode.
• Higher-risk clinical pattern: Female sex, a non-shockable rhythm, and no clear alternate cause clustered with higher ICH prevalence, although rhythm alone was not accurate enough to serve as a stand-alone predictor.
• Headache before collapse: Prodromal headache was a meaningful red flag for intracranial hemorrhage, but about half of patients had no reported symptoms before arrest, so absence of warning symptoms does not reassure.
• Prognostic weight of ICH: Neurologic causes of OHCA had devastating outcomes in the included data, with one study reporting 100% mortality versus 65% for non-neurologic causes, making CT useful for prognosis as well as cause-finding.
• Evidence limits and bias: The signal is clinically important, but the studies were heterogeneous and at risk of bias, so the take-home is to strongly consider head CT after ROSC rather than to scan every patient automatically.