The Centers for Medicare and Medicaid Services Severe Sepsis and Septic Shock Management Bundle (SEP-1) assesses antibiotic administration, lactate measurement, and blood culture collection within 3 h of severe sepsis onset. The impact of the SEP-1 3-hour bundle among patients with severe sepsis is not extensively described. This investigation aimed to describe the impact of 3-hour bundle compliance on 28-day in-hospital mortality in patients with severe sepsis.
This was a retrospective, propensity adjusted, nested case-control study assessing the impact of compliance with a 3-hour sepsis bundle among patients with severe sepsis.
This study was conducted at a large, academic, tertiary care medical center in Detroit, Michigan from July 1, 2017 to December 31, 2019.
Cases were defined as those suffering 28-day in-hospital mortality. Controls were defined as those surviving at or discharged by 28 days. Patients were separated based on 3-hour bundle compliance or noncompliance. Nested and overall cohorts were assessed. Severe sepsis time zero was manually validated. Patients with shock, requiring vasopressors within 8 h of time zero, or those not meeting SEP-1 inclusion criteria were excluded.
The primary outcome was the propensity adjusted odds of 28-day in-hospital mortality among 3-hour bundle compliant versus noncompliant patients. Secondary outcomes included mortality for individual bundle element compliance, progression to septic shock, and predictors of mortality according to logistic regression.
A total of 325 compliant and 325 noncompliant patients were included. The median Sequential Organ Failure Assessment (SOFA) score was three in each group. There was no difference in propensity adjusted odds of mortality among those compliant versus noncompliant with the 3-hour bundle (odds-ratio [OR] 1.039; 95% CI: 0.721-1.497; p = 0.838) or with individual bundle elements. SOFA score and female sex were predictors of mortality.
Three-hour bundle compliance did not impact 28-day in-hospital mortality in patients with severe sepsis. Further research is needed to understand the impact of 3-hour bundle compliance on mortality in severe sepsis.

Propensity score methods are increasingly being used in the infectious diseases literature to estimate causal effects from observational data. However, there remains a general gap in understanding among clinicians on how to critically review observational studies that have incorporated these analytic techniques.
Using a cohort of 4967 unique patients with Enterobacterales bloodstream infections, we sought to answer the question \"Does transitioning patients with gram-negative bloodstream infections from intravenous to oral therapy impact 30-day mortality?\" We conducted separate analyses using traditional multivariable logistic regression, propensity score matching, propensity score inverse probability of treatment weighting, and propensity score stratification using this clinical question as a case study to guide the reader through (1) the pros and cons of each approach, (2) the general steps of each approach, and (3) the interpretation of the results of each approach.
2161 patients met eligibility criteria with 876 (41%) transitioned to oral therapy while 1285 (59%) remained on intravenous therapy. After repeating the analysis using the 4 aforementioned methods, we found that the odds ratios were broadly similar, ranging from 0.84-0.95. However, there were some relevant differences between the interpretations of the findings of each approach.
Propensity score analysis is overall a more favorable approach than traditional regression analysis when estimating causal effects using observational data. However, as with all analytic methods using observational data, residual confounding will remain; only variables that are measured can be accounted for. Moreover, propensity score analysis does not compensate for poor study design or questionable data accuracy.