Severe sepsis: variation in resource and therapeutic modality use among academic centers

Abstract

Background: Treatment of severe sepsis is expensive, often encompassing a number of discretionary modalities. The objective of the present study was to assess intercenter variation in resource and therapeutic modality use in patients with severe sepsis.

Methods: We conducted a prospective cohort study of 1028 adult admissions with severe sepsis from a stratified random sample of patients admitted to eight academic tertiary care centers. The main outcome measures were length of stay (LOS; total LOS and LOS after onset of severe sepsis) and total hospital charges.

Results: The adjusted mean total hospital charges varied from 69 429 dollars to US237 898 dollars across centers, whereas the adjusted LOS after onset varied from 15.9 days to 24.2 days per admission. Treatments used frequently after the first onset of sepsis among patients with severe sepsis were pulmonary artery catheters (19.4%), ventilator support (21.8%), pressor support (45.8%) and albumin infusion (14.4%). Pulmonary artery catheter use, ventilator support and albumin infusion had moderate variation profiles, varying 3.2-fold to 4.9-fold, whereas the rate of pressor support varied only 1.92-fold across centers. Even after adjusting for age, sex, Charlson comorbidity score, discharge diagnosis-relative group weight, organ dysfunction and service at onset, the odds for using these therapeutic modalities still varied significantly across centers. Failure to start antibiotics within 24 hours was strongly correlated with a higher probability of 28-day mortality (r2 = 0.72).

Conclusion: These data demonstrate moderate but significant variation in resource use and use of technologies in treatment of severe sepsis among academic centers. Delay in antibiotic therapy was associated with worse outcome at the center level.

Figure 1

Variation in odds ratios (ORs) for therapeutic modalities. C1 was the reference center. ORs were calculated after adjusting for age, sex, Charlson comorbidity score and discharge diagnosis-related group weight, organ dysfunction, and service at onset of sepsis. Albumin, on albumin within 24 hours after onset; Antibiotic, antibiotic given within 24 hours after onset; CI, confidence interval; PA, pulmonary artery; Pressor, pressor support; Ventilator, ventilator support.

Figure 2

Variation in odds ratios (ORs) for outcomes. C1 was the reference center. ORs were calculated after adjusting for age, sex, Charlson comorbidity score, and discharge diagnosis-related group weight, organ dysfunction, and service at onset of sepsis. ARDS, acute respiratory distress syndrome; CI, confidence interval; DIC, disseminated intravascular coagulation.

Figure 3

Relationship between mortality rate and antibiotic use. This plot displays the mortality rate versus whether an antibiotic was given within 24 hours after sepsis onset in the eight centers. The results were significant for (a) all patients (n = 1028) and (b) for the subgroup (n = 924) after excluding those with a 'do not resuscitate' order (n = 104).