# Effects of Intravenous Versus Intraosseous Adrenalin Administration on Morbidity and Mortality After Out-of-Hospital Cardiac Arrest: A Systematic Review

## TL;DR

This paper reviews studies comparing intravenous and intraosseous adrenaline administration for cardiac arrest, finding limited evidence to determine which method is better.

## Contribution

The study systematically reviews clinical outcomes of IV versus IO adrenaline administration for OHCA, highlighting the lack of conclusive evidence.

## Key findings

- Nine studies were included, but significant heterogeneity prevented a meta-analysis.
- No firm conclusions could be drawn about which administration route improves outcomes.
- Most studies were retrospective or sub-analyses, limiting the strength of evidence.

## Abstract

Background and Objectives: Out-of-hospital cardiac arrest (OHCA) is a common manifestation of heart disease and a leading cause of death in western societies with an overall survival rate of 10%. Guidelines generally prefer the peripheral intravenous (IV) access as the first option for OHCA patients, leaving the intraosseous (IO) route for patients in which IV access is not feasible or unsuccessful. This systematic review will purely focus on the clinical differences between adrenaline administered via the IO route compared to the IV route and its effects on morbidity and mortality after OHCA. Materials and Methods: A multi-database (PubMed, Medline, Embase, and The Cochrane Library) was performed and was searched between the earliest date of each database and 16 February 2024. For data extraction, a structured checklist was used, including type of study, the number of patients, age, gender, Return of Spontaneous Circulation (ROSC), associated morbidity, mortality, neurological, and general outcome. Results: The initial literature search produced 1772 results. After screening for title and abstract, a total of nine studies were included in our systematic review. Of these studies, six were retrospective cohort studies, one prospective study, and two sub-analyses of previous randomized trials. Due to significant heterogeneity, a meta-analysis was not performed. Conclusions: In our systematic review we have found a small number of studies comparing IV and IO adrenaline administration during cardiac arrest. Due to significant heterogeneity, a meta-analysis was not performed and no firm conclusions could be drawn about which route of adrenalin administration leads to better outcomes.