(1473) The Impact of Preadmission Bariatric Surgery on Sepsis Outcomes in Surgical Patients

Introduction: We have shown that obesity is associated with higher 90-day mortality compared to non-obese surgical patients. Bariatric surgery (BS) reduces obesity-related comorbidities, even in those who remain obese. The objective of this study was to evaluate the impact of prior BS on sepsis outcomes in obese surgical patients, which we hypothesized would be associated with improved 90-day survival.

Methods: A retrospective review of all surgical patients with sepsis (SOFA≥2) was conducted at a single institution. Patients were grouped into obese with prior BS (OB/BS, n=48), obese without BS (OB, n=718), and non-obese (BMI:18.5-29.9kg/m2) (NOB, n=574). Demographic data, comorbidities, and sepsis presentation were compared. The primary outcome was 90-day mortality and survival. Secondary outcomes included need for renal replacement therapy (RRT), length of stay, and discharge disposition. A p< 0.05 was significant.

Results: Most OB/BS patients underwent gastric bypass < 5 years from admission (61%). This group was younger and more likely to be female and transferred from an outside hospital. The mean BMI was highest in the OB/BS group (46.3±14.7 vs OB: 39.5±9.7 vs NOB: 25.2±3.0, p< 0.005). Charlson Comorbidity Index was lower in the OB/BS group (2 (1-4) vs 4 (2-6) vs 4 (2-6), p=0.008). Intra-abdominal and soft tissue infections were the most common sepsis etiologies. Admission SOFA and vasopressor use was comparable between groups. Cumulative 90-day mortality was significantly lower in the OB/BS cohort (20.8% vs OB: 35.4% vs NOB: 26.3%, p=0.001). Compared to the OB and NOB groups, need for RRT and dependent discharge were lowest in the OB/BS group. The OB/BS cohort was more likely to die from intra-abdominal sepsis not amenable to source control (60% vs 22.5% vs 22.8%, p=0.02). Compared to the other groups, 90-day survival was highest in the OB/BS cohort (logrank p=0.0008).

Conclusions: Although the cohort was small, this study demonstrated significant improvement in 90-day survival in OB/BS patients despite higher BMIs, which may be due to reduced pre-admission comorbidities. This group was more likely to die from intra-abdominal sources, likely reflecting surgical complexity with prior bypasses. Future studies are needed to evaluate how BS modulates immunologic competency during sepsis.