Background: Pre-filled syringes are increasingly popular in medicine, especially in emergency medicine, where fast intervention is crucial. Additionally, as indicated by numerous studies, the use of drugs in prefilled syringes reduces the risk of medical errors associated with inadequate preparation of the drug and reduces the risk of contamination as a result of tissue injury due to rupture of a standard ampoule with the drug. The aim of the study was to compare the use of pre-filled syringes with adrenaline and standard adrenaline in ampoules during simulated CPR during simulated cardiopulmonary resuscitation in non-shockable rhythms performed by two-person teams. Methods: The study was a randomised cross-over study and was based on medical simulation. The study involved 40 paramedics assigned randomly to 20 two-person rescue teams. These teams were to perform 10-minute cardiopulmonary resuscitation in three research scenarios: Scenario A — During CPR, access to the median basilic vein and preparation and administration of adrenaline infusions from generally available ampoules at concentration 1:1000 were required (Adrenaline WZF 0.1%; Polfa, Warsaw, Poland) with a standard syringe; Scenario B — During resuscitation, the median basilic vein was accessed and adrenaline was to be administered from an adrenaline pre-filled syringe (Aguettant Sante, Lyon, France); Scenario C — During CPR, intraosseous tibial vascular access was obtained using a NIO Adult kit, and adrenaline was administered using a pre-filled syringe with adrenaline (Aguettant Sante, Lyon, France). Both the order of resuscitation and medication administration as well as the order of participants were random. Results : The time to obtain vascular access in the examined scenarios varied and was 240 sec [IQR; 220–265] for Scenario A, 236 sec [IQR; 210–270] for Scenario B, and 165 sec [IQR; 90–180] for Scenario C; A vs. C, (p < 0.001), B vs. C (p < 0.001). In scenarios A, B, and C, the duration of adrenaline administration varied and was 55 sec [IQR; 50–85] vs. 20 sec [IQR; 18–35] vs. 20 sec [IQR; 20–30] (A vs. B, and A vs. C, p < 0.001). Conclusion: A simulation study has shown that paramedics in two-person teams are unable to deliver adrenaline at the time recommended by CPR guidelines. The delay of CPM adrenaline supply compared to PFS adrenaline is statistically significant. In the opinion of paramedics participating in the study, adrenaline during resuscitation should be administered by means of pre-filled syringes, which eliminates the delays in rescue operations resulting from the time needed to prepare drugs as well as limited human resources in rescue teams.