Granfeldt A, Avis SR, Lind PC, et al. - Researchers analyzed literature data to study intravenous (IV) vs intraosseous (IO) administration of drugs during cardiac arrest, to ultimately inform an update of international guidelines. They explored Medline, Embase and Evidence-Based Medicine Reviews for reports comparing IV to IO administration of drugs. Overall six observational studies were analyzed. Two randomized trials, evaluating the influence of particular drugs in subgroups associated with IV vs IO administration, were also included. Adult out-of-hospital cardiac arrest patients were involved in all studies. Experts found a limited number of investigations comparing IV vs IO administration of drugs during cardiac arrest. IV access was favored by pooled outcomes from four observational studies, with very low certainty of evidence. Findings revealed no statistically significant interaction between the route of access and study drug on results, in the subgroup studies of two randomized clinical trials.