211. Outcomes Following a Protocol Change to decrease Perioperative Antibiotic Duration Among Liver Transplant Recipients

Abstract Background Liver transplant recipients (LTRs) are at high risk for infections. The optimal duration of perioperative antibacterial prophylaxis remains unclear, particularly in patients hospitalized prior to transplant. Our study examines the impact of a change in our institutional perioperative antibiotic protocol in LTRs on post-transplant infection and antibiotic-associated toxicity. Methods We conducted a retrospective cohort study of all adult LTRs at our center who underwent transplant from 1/1/2018 until 9/1/2021. Patients were categorized as low risk if they are hospitalized < 24 hours prior to transplant and high risk if they were hospitalized ≥ 24 hours prior to transplant. We investigated patient outcomes after a change to our perioperative antibiotic guideline on 1/19/21, which reduced the duration of post-operative antibiotics for low risk patients from 48 to 24 hours and for high risk patients from 5 days or duration of post-operative ICU stay to 72 hours. Outcomes included post-transplant infection within 30 days (composite outcome of bacteremia and surgical site infection), C. difficile infection (CDI), and isolation of multi-drug resistant organisms (MDROs) from any site. Chi-squared and Fisher’s exact test were performed with p < 0.05 considered significant. Results There were 154 LTRs who underwent transplantation during the study period, including 63 high risk patients (43 before and 20 after the protocol change). The median duration of prophylactic antibiotics in the high risk group decreased from 6 (IQR 5-8) to 4.5 (IQR 4-5) days after the protocol change (p = 0.04), and in the low risk group decreased from 2.5 (IQR 2-5) to 1 (IQR 1-2) day (p = 0.04). Prophylactic antibiotics consisted of piperacillin-tazobactam in 145 (94%) and vancomycin in 104 (68%) of cases. In the high risk group, infection occurred in 4 (9%) patients before and 0 patients after the protocol change (p=0.3). CDI occurred in 4 (9%) patients before and 1 (5%) patient after the protocol change (p=1). Resistant organisms were isolated in 10 (23%) patients before and 1 (5%) patient after the protocol change (p=0.15). Figure 1.Antibiotic duration as a percentage of each cohortTable 1.Clinical outcomes before and after protocol change among low and high risk patientsTable 2.Antibiotic-associated outcomes before and after protocol change among low and high risk patients Conclusion The policy change reduced the median duration of perioperative antibiotic prophylaxis but was not accompanied by an observed increase in postoperative infection. Disclosures All Authors: No reported disclosures.