LAUSR

RATIONALE In 2017, the U.S. Centers for Disease Control and Prevention (CDC) developed a new surveillance definition of sepsis, the adult sepsis event (ASE), to better track sepsis epidemiology. The ASE requires evidence of acute organ dysfunction and defines baseline organ function pragmatically as the best in-hospital value. This approach may undercount sepsis if new organ dysfunction does not resolve by discharge. OBJECTIVE To understand how sepsis identification and outcomes differ when using the best laboratory values during hospitalization versus methods that use historical look-backs to define baseline organ function. METHODS We identified all patients hospitalized at 138 Veterans Affairs hospitals (2013-2018) admitted via the emergency department with 2+ systemic inflammatory response (SIRS) criteria, were treated with antibiotics within 48 hours (i.e. had potential infection), and completed 4+ days of antibiotics (i.e. had suspected infection). We considered 3 approaches to defining baseline renal, hematologic, and liver function: the best values during hospitalization (as in the CDC's ASE), the best values during hospitalization plus prior 90 days (3-month baseline) and the best values during hospitalization plus prior 180 days (6-month baseline). We determined how many patients met criteria for sepsis by each approach, then compared characteristics and outcomes of sepsis hospitalizations between the 3 approaches. RESULTS Among 608,128 hospitalizations with potential infection, 72.1%, 68.5%, and 58.4% had creatinine, platelet, and total bilirubin measured, respectively, in the prior 3 months. 86.0%, 82.6%, and 74.8%, respectively, had these labs in the prior 6 months. Using the hospital baseline, 100,568 hospitalizations met criteria for community-acquired sepsis. By contrast, 111,983 and 117,435 met criteria for sepsis using the 3- and 6-month baselines for a relative increase in 11% and 17%, respectively. Patient characteristics were similar across the 3 approaches. In-hospital mortality was 7.2%, 7.0%, and 6.8% for sepsis hospitalizations identified using the hospital, 3-month, and 6-month baselines. 30-day mortality was 12.5%, 12.7%, and 12.5%, respectively. CONCLUSIONS Among Veterans hospitalized with potential infection, the majority had laboratory values in the prior 6 months. Using 3- and 6-month look-backs to define baseline organ function resulted in an 11% and 17% relative increase, respectively, in the number of sepsis hospitalizations identified.