159. Antibiotic and diagnostic stewardship surrounding pre-operative testing in patients undergoing cardiac surgery

Abstract Background Despite national guidelines from the US Preventative Services Task Force and the Infectious Diseases Society of America that recommend against screening for asymptomatic bacteriuria (ASB, defined as > 105 CFU of an organism) in most circumstances, pre-operative screening urine culture (UCx) continues. Detection and treatment of ASB leads to antibiotic exposure and risk of antibiotic-associated adverse events like drug reactions, Clostridioides difficile infection (CDI), and colonization by drug-resistant organisms. We describe the implementation of eliminating pre-operative screening for ASB in patients undergoing cardiac surgery. Figure 1Pre-operative checklist for cardiac surgery prior to intervention Methods This was a pre-post study of practice change involving removing ASB screening as part of the pre-cardiac surgery checklist (Figure 1). The pre-intervention period was 08/18/21 – 11/17/21, the post intervention period was 12/1/21 – 3/1/22. We identified all patients who underwent a cardiac arterial bypass graft procedure with or without vein harvesting. We reviewed pre-operative UCx, test indication, antibiotic administration pre-operatively due to culture growth, and post-operative CDI and CAUTI within 30 days post procedure identified through routine infection prevention and control surveillance. Results Pre-intervention, 117/128 (91.4%) patients undergoing cardiac surgery had a UCx collected. Of the UCx, 100% were ordered as part of the pre-operative checklist and not for symptoms. Five patients pre-intervention had ASB detected. Four patients received antibiotics to treat ASB. A fifth patient received antibiotics for bacteriuria which did not meet ASB count threshold. Post-intervention, 15/123 had a UCx (12.3%). Of these, 12/15 were ordered as part of the pre-operative checklist (80%), and the remaining three had symptoms documented. Post-intervention, one patient had ASB detected and did not receive antibiotics. Pre- and post-intervention there were 2 cases of CDI (2/128, 1.6% and 2/123, 1.6%, respectively). There were no CAUTIs either pre- or post-intervention. Conclusion Standard pre-operative UCx is known to be a low-value test and is not recommended by national guidelines. In this single-center diagnostic stewardship intervention, screening was reduced by 87.2%. There was no change in infectious outcomes. Disclosures All Authors: No reported disclosures.