Objective: The Intravenous versus Intraosseous Vascular Access for Out-of-Hospital Cardiac Arrest (IVIO) trial was a randomised clinical trial that investigated initial vascular access strategy for out-of-hospital cardiac arrest. The current manuscript presents outcomes at 6 months and 1 year.
Methods: Adults with non-traumatic out-of-hospital cardiac arrest, in whom vascular access was indicated, were randomised to initial intraosseous or intravenous access. The allocated method was attempted up to two times. Prespecified 6-months and 1-year outcomes included survival, survival with a favourable neurological outcome, defined as a modified Rankin Scale score of 0-3, and health-related quality-of-life assessed using the EuroQoL 5-Dimension 5-Level questionnaire on domains of mobility, self-care, usual activities, pain/discomfort, and anxiety/depression.
Results: Of the 1479 patients included in the main manuscript primary analyses, three were lost to follow-up for 1-year survival. At 1 year, 82 patients (11%) in the intraosseous group and 68 patients (9%) in the intravenous group were alive (risk ratio 1.24; 95% confidence interval 0.91-1.67). Survival with a favourable neurological outcome was observed in 76 patients (10%) and 61 patients (8%), respectively (risk ratio 1.28; 95% confidence interval 0.93-1.77). Among survivors, the mean EQ-5D-5L numeric score was 83 in the intraosseous group and 76 in the intravenous group (mean difference 7; 95% confidence interval 1-13).
Conclusion: Long-term outcomes were similar between patients who received initial intraosseous versus intravenous vascular access during adult out-of-hospital cardiac arrest. These findings do not support a difference in patient outcomes between the two vascular access strategies.
Trial registration: EU Clinical Trials number 2022-500744-38-00; ClinicalTrials.gov number NCT05205031.
Keywords: Advanced life support; Cardiac arrest; Clinical trial; Vascular access.
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