Despite over a decade worth of reviews, including some large RCTs, no-one has been able to prove any advantage for Vasopressin over Epinephrine in Cardiac arrest. And neither does this meta-analysis of six RCTs published from 1997 to 2010. They pooled the results from 4475 adult patients but weren’t able to identify any benefit in ROSC nor long-term survival with Vasopressin over Epinephrine. The authors do leave an minor opening though.
Patients with cardiac arrest presenting with asystole and who are treated with vasopressin might have increased long-term survival.
Find the study by Metzenopoulus et al here. Abstract below.