Background: Traditionally, radiologists have routinely recommended oral contrast agents (such as Telebrix®) for patients undergoing a computed tomography of the abdomen/pelvis (CTAP), but recent evidence has shown limited diagnostic benefits for most emergency department (ED) patients. Additionally, the use of oral contrast has numerous drawbacks, including patient nausea/vomiting, risk of aspiration and delays to CTAP completion and increased ED length of stay (LOS). Aim Statement: The aim was to safely reduce the number of ED patients receiving oral contrast prior to undergoing CTAP and thereby reduce ED length of stay. Measures & Design: An evidence-based ED protocol was developed in collaboration with radiology. PDSA cycle #1 was implementation at a pilot site to identify potential barriers. Challenges identified included the need to change the electronic order sets to reflect the new protocol, improved communication with frontline providers and addition of an online BMI calculator. PDSA cycle #2 was widespread implementation across all 4 ED's in the Calgary zone. The protocol was incorporated into all relevant electronic ED order sets to act as a physician prompt. Using administrative data, we extracted and analyzed data using descriptive and inferential statistics for the outcomes and balancing measures from a period of 12 months pre- and 12 months post-intervention. Evaluation/Results: A total of 14,868 and 17,995 CTAP exams were included in the pre and post periods, respectively. There was a reduction in usage of oral contrast from 71% to 30% (P < 0.0001) in the pre- and post-study period, respectively. This corresponded to a reduction in average time of CT requisition to CT report completed from 3.30 hours to 2.31 hours (-0.99 hrs, P = 0.001) and a reduction in average ED LOS from 11.01 hours to 9.92 hours (-1.08 hrs, P < 0.0001). The protocol resulted in a reduction of 19,434.6 patient hrs in the ED. Run charts demonstrate change was sustained over time. Our protocol did not demonstrate an increase in rates of repeat CTAP (P = 0.563) at 30 days, nor an increase in patient re-admission within 7 days (P = 0.295). Discussion/Impact: Successful implementation of an ED and radiology developed protocol significantly reduced the use of oral contrast in patients requiring enhanced CTAP as part of their diagnostic work up and, thereby, reduced overall ED LOS without increasing the need for repeat examinations within 30 days or re-admission within 7 days.