Resident physicians are often required to perform central venous catheter (CVC) or intraosseous catheter (IO) placement when supervision is not readily available. We assessed whether brief CVC and IO simulation-based training increases resident knowledge and comfort performing these procedures unsupervised. Residents were assigned to either a 60-minute CVC training or a control group that received no training; they were also assigned to either a 30-minute IO training or a control group. Both trainings improved resident comfort performing the respective procedures (47% CVC intervention group vs. 26% CVC control group, p = 0.051; 47% IO intervention group vs. 16% IO control group, p = 0.006). There was also a statistically-significant summative effect of receiving both trainings, as 75% of the residents who received both trainings reported comfort obtaining unsupervised emergent vascular access. This suggests that residencies should include not only CVC, but also IO, simulation-based training sessions to prepare residents for emergency situations.