Volume of emergency department admissions for sepsis is related to inpatient mortality: results of a nationwide cross-sectional analysis

Abstract

Objectives: Emergency department resuscitation plays a significant role in sepsis care, and it is unknown if patient outcomes vary by institution based on the level of sepsis experience of the emergency department. This study examines whether there is an association between the annual volume of patients admitted via the emergency department with sepsis and inpatient mortality.

Design: Cross-sectional analysis of the 2007 Nationwide Inpatient Sample.

Setting and patients: We included 87,166 adult emergency department sepsis admissions from 551 hospitals.

Measurements: Hospitals were categorized into quartiles by 2007 emergency department sepsis volume. Univariate associations of patient characteristics, hospital characteristics, and inpatient mortality with sepsis volume level were evaluated by chi-square test. A population-averaged logistic regression model of inpatient mortality was used to estimate the effects of age, gender, comorbid conditions, payer status, median zip code income, hospital bed size, teaching status, and emergency department sepsis volume.

Main results: Overall inpatient sepsis mortality was 18.0% and early mortality (2 days after admission) was 6.9%. The risk-adjusted odds ratios of mortality were 0.73 (95% confidence interval, 0.64-0.83; p < .001) in quartile 4 (highest volume), 0.83 in quartile 3 (95% confidence interval, 0.74-0.93; p = .001), and 0.90 in quartile 2 (95% confidence interval, 0.82-0.99; p < .05) when compared to quartile 1 (lowest volume). Adjusted results were similar for early mortality: 0.69 (95% confidence interval, 0.61-0.76; p < .001) in quartile 4, 0.83 in quartile 3 (95% confidence interval, 0.74-0.93; p < .05), and 0.85 in quartile 2 (95% confidence interval, 0.77-0.94; p < .05) when compared to quartile 1.

Conclusions: After adjustment for comorbidity and hospital-level factors, there was a significant relationship between emergency department sepsis case volume and overall and early inpatient mortality among patients admitted through the emergency department with sepsis. Patients admitted to hospitals in the highest-volume quartile had 27% lower odds of inpatient mortality in this large heterogeneous sample.