INTRODUCTION: Successful completion of inpatient colonoscopies is often impeded by patient ability to undergo adequate bowel preparation prior to their exam. Inadequate colonoscopy preparation places patients at risk for an aborted or incomplete procedure, leading to delay in diagnosis, additional exposure to anesthesia and increased hospital stay. METHODS: Fishbone analysis revealed multiple areas of potential intervention that could translate to improvement in the quality of inpatient colonoscopy preparations (Figure 1). Specifically, there was an identified issue of timely delivery of miralax and gatorade preps to patients. A fellow-wide collective quality improvement initiative to prevent all aborted inpatient colonoscopies was started July 2018, with standardization of inpatient bowel preparation to polyethylene glycol 3350 (Nulytely), and gastroenterology fellows standardized inpatient workflows to check on adequacy of bowel preps during AM pre-rounding. Using an intention to scope analysis, inpatient colonoscopies from January 2018 through June 2019 were reviewed to determine number of exams that were aborted (outcome measure) or cancelled (balancing measure). Proportions of aborted colonoscopies were compared using Chi-square and postponed colonoscopies reported as a p-control chart. RESULTS: Aborted procedures were overall rare, but notably, there was a decrease in the number of aborted procedures over time, 2.31% to 0.66%, although this result was not significant (P = 0.39) (Figure 2). The rate of postponed procedures due to inadequate preparation was overall low throughout the study period (4.6%, 19/410), and the process appeared to be in control from month to month (Figure 3). CONCLUSION: Fishbone mapping lead to identification of a colonoscopy preparation bottleneck with miralax and gatorade preparations, for which standard NuLytely preparations were implemented. A fellowship wide intervention did reduce the number of aborted colonoscopies by 75% in the final 6 months, however the overall number of aborted colonoscopies pre and early intervention period was low. We suspected that this intervention may cause an increase in postponed procedures for additional prep, but we did not see this pattern. After further understanding the process and identifying barriers, standard inpatient bowel preparation and fellow workflow trended towards elimination of aborted colonoscopies without a concomitant rise in postponed procedures.Figure 1.: Fishbone analysis of poor prep on inpatient colonoscopy.Figure 2.: Proportion of aborted colonoscopies per six month interval.Figure 3.: P-control chart of postponed colonoscopies.