The Relationship Between Hospital Capability and Mortality in Sepsis: Development of a Sepsis-Related Hospital Capability Index

Abstract

Objectives: Regionalized sepsis care could improve sepsis outcomes by facilitating the interhospital transfer of patients to higher-capability hospitals. There are no measures of sepsis capability to guide the identification of such hospitals, although hospital case volume of sepsis has been used as a proxy. We evaluated the performance of a novel hospital sepsis-related capability (SRC) index as compared with sepsis case volume.

Design: Principal component analysis (PCA) and retrospective cohort study.

Setting: A total of 182 New York (derivation) and 274 Florida and Massachusetts (validation) nonfederal hospitals, 2018.

Patients: A total of 89,069 and 139,977 adult patients (≥ 18 yr) with sepsis were directly admitted into the derivation and validation cohort hospitals, respectively.

Interventions: None.

Measurements and main results: We derived SRC scores by PCA of six hospital resource use characteristics (bed capacity, annual volumes of sepsis, major diagnostic procedures, renal replacement therapy, mechanical ventilation, and major therapeutic procedures) and classified hospitals into capability score tertiles: high, intermediate, and low. High-capability hospitals were mostly urban teaching hospitals. Compared with sepsis volume, the SRC score explained more variation in hospital-level sepsis mortality in the derivation (unadjusted coefficient of determination [ R2 ]: 0.25 vs 0.12, p < 0.001 for both) and validation (0.18 vs 0.05, p < 0.001 for both) cohorts; and demonstrated stronger correlation with outward transfer rates for sepsis in the derivation (Spearman coefficient [ r ]: 0.60 vs 0.50) and validation (0.51 vs 0.45) cohorts. Compared with low-capability hospitals, patients with sepsis directly admitted into high-capability hospitals had a greater number of acute organ dysfunctions, a higher proportion of surgical hospitalizations, and higher adjusted mortality (odds ratio [OR], 1.55; 95% CI, 1.25-1.92). In stratified analysis, worse mortality associated with higher hospital capability was only evident among patients with three or more organ dysfunctions (OR, 1.88 [1.50-2.34]).

Conclusions: The SRC score has face validity for capability-based groupings of hospitals. Sepsis care may already be de facto regionalized at high-capability hospitals. Low-capability hospitals may have become more adept at treating less complicated sepsis.