b'Scientific Session Abstracts SATURDAY APRIL 20, 2024 3: A NOVEL PREOPERATIVE RISK SCORE TO IDENTIFY PATIENTS AT HIGH RISK FOR NON-HOME DISCHARGE AFTER ELECTIVE OPEN ABDOMINAL AORTIC ANEURYSM REPAIRJoel L. Ramirez 1 , Eric Sung 2 , Warren J. Gasper 1 , Michael S. Conte 1 ,Laura T, Boitano 3 , Jesus G. Ulloa 4, 5 , James C. Iannuzzi 11 Department of Surgery, Division of Vascular and Endovascular Surgery, University of California, San Francisco, San Francisco, CA, USA,2 Department of Surgery, Division of Vascular and Endovascular Surgery, Boston Medical Center, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA,3 University of Massachusetts Chan School of Medicine, Worcester, MA, USA , 4 David Geffen School of Medicine, University of California, Los Angeles, CA, USA.,5West Los Angeles Veterans Health Administration, Los Angeles, CA, USA.Background: Non-home discharge (NHD) to a rehabilitation or skilled nursing facility after vascular surgery is poorly described despite its impact on patients. For home-dwelling patients undergoing elective surgery, the need for postoperative NHD can have meaningful implications on quality of life, long-term outcomes, and healthcare spending. Understanding post-surgical NHD risk is essential to preoperative counseling and shared decision making. This is particularly true for the treatment of abdominal aortic aneurysms as the postoperative course can vary between open and endovascular surgery. We aimed to identify independent predictors of NHD following elective open abdominal aortic aneurysm repair (OAR), and to create a clinically useful preoperative risk score.Methods: Elective OAR cases were queried from the SVS Vascular Quality Initiative from 2013 to 2022. A risk score was created by splitting the data set into two-thirds for development and one-third for validation. A parsimonious stepwise hierarchical multivariable logistic regression controlling for hospital level variation was performed in the development dataset, and the beta- coefficients were used to assign points for a risk score. The score was then validated, and model performance assessed.Results: Overall, 8,274 patients were included and 1,502 (18.2%) required NHD. At baseline, patients who required NHD were more likely to be80 years old (23.6% vs. 6.5%), female (35.9% vs. 23.1%), not independently ambulatory (14.6% vs. 4.3%), anemic (24.4% vs. 13.9%), and have COPD (41.6% vs. 30.7%), American Society of Anesthesiologists (ASA) class4 (41.0% vs. 32.5%), and a supraceliac proximal clamp (9.8% vs. 5.7%; all P0.05). Multivariable analysis in the development group identified the following independent predictors of NHD: age80 years, not independently ambulatory, proximal clamp location, hypogastric artery occlusion, anemia (Hb 12 g/dL), chronic obstructive pulmonary disease, female sex, hypertension, 38SOUTHERN CALIFORNIA VASCULAR SURGICAL SOCIETY'