Impact of the diagnostic process on the accuracy of source identification and time to antibiotics in septic emergency department patients.

OBJECTIVE: Timely administration of effective antibiotics is important in sepsis management. Source-targeted antibiotics are believed to be most effective, but source identification could cause time delays. OBJECTIVES: First, to describe the accuracy/time delays of a diagnostic work-up and the association with time to antibiotics in septic emergency department (ED) patients. Second, to assess the fraction in which source-targeted antibiotics could have been administered solely on the basis of patient history and physical examination. METHODS: Secondary analysis of the prospective observational study on septic ED patients was carried out. The time to test result availability was associated with time to antibiotics. The accuracy of the suspected source of infection in the ED was assessed. For patients with pneumosepsis, urosepsis, and abdominal sepsis, combinations of signs and symptoms were assessed to achieve a maximal positive predictive value for the sepsis source, identifying a subset of patients in whom source-targeted antibiotics could be administered without waiting for diagnostic test results. RESULTS: The time to antibiotics increased by 18 (95% confidence interval: 12-24) min/h delay in test result availability (n=323). In 38-79% of patients, antibiotics were administered after additional tests, whereas the ED diagnosis was correct in 68-85% of patients. The maximal positive predictive value of signs and symptoms was 0.87 for patients with pneumosepsis and urosepsis and 0.75 for those with abdominal sepsis. Use of signs and symptoms would have led to correct ED diagnosis in 33% of patients. CONCLUSION: Diagnostic tests are associated with delayed administration of antibiotics to septic ED patients while increasing the diagnostic accuracy to only 68-85%. In one-third of septic ED patients, the choice of antibiotics could have been accurately determined solely on the basis of patient history and physical examination.

The prognostic performance of the predisposition, infection, response and organ failure (PIRO) classification in high-risk and low-risk emergency department sepsis populations: comparison with clinical judgement and sepsis category.

OBJECTIVE: To compare the prognostic performance of the predisposition, infection, response and organ failure (PIRO) score with the traditional sepsis category and clinical judgement in high-risk and low-risk Dutch emergency department (ED) sepsis populations. METHODS: Prospective study in ED patients with severe sepsis and septic shock (high-risk cohort), or suspected infection (low-risk cohort). OUTCOME: 28-day mortality. Prognostic performance of PIRO, sepsis category and clinical judgement were assessed with Cox regression analysis with correction for quality of ED treatment and disposition. Illness severity measures were divided into four groups with the lowest illness severity as reference category; discrimination was quantified by receiver operator characteristics with area under the curve (AUC) analysis. RESULTS: Death occurred in 72/323 (22%, high-risk) and 23/385 (6%, low-risk) patients. For the low-risk cohort, corrected HRs (95% CI) for categories 2-4 were 2.0 (0.4 to 11.9), 4.3 (0.8 to 24.7) and 17.8 (2.8 to 113.0: PIRO); 0.5 (0.05 to 5.4), 2.1 (0.2 to 21.8) and 7.5 (0.6 to 92.9: sepsis category). Patients discharged home (category 1) all survived. HRs were 4.5 (0.5 to 39.1) and 13.6 (4.3 to 43.5) for clinical judgement categories 3-4. Prognostic performance was consistently better in the low-risk than in the high-risk cohort. For PIRO AUCs were 0.68 (0.61 to 0.74; high-risk) and 0.83 (0.75 to 0.91; low-risk); for sepsis category AUCs were 0.50 (0.42 to 0.57; high-risk) and 0.73 (0.61 to 0.86; low-risk); for clinical judgement AUCs were 0.69 (0.60 to 0.78; high-risk) and 0.84 (0.73 to 0.96; low-risk). CONCLUSIONS: The accuracy and discriminative performance of the PIRO score and clinical judgement are similar, but better than the sepsis category. Prognostic performance of illness severity scores is less in high-risk cohorts, while in high-risk populations a risk stratification tool would be most useful.

Performance of illness severity scores to guide disposition of emergency department patients with severe sepsis or septic shock.

OBJECTIVE: To determine the number of emergency department (ED) patients with severe sepsis who are admitted to the ICU and to assess whether the predisposition, infection, response and organ failure (PIRO) score can be used as a clinical decision-making tool for guiding the disposition of ED sepsis patients to wards or the ICU. METHODS: This is a prospective study including ED patients with severe sepsis and septic shock. The PIRO score and in-hospital mortality were assessed in patients admitted to wards and ICUs. The sensitivity and specificity of the PIRO score and clinical judgement of the ED physician for guiding adequate disposition to wards or the ICU were assessed. RESULTS: A total of 47 of 153 patients were admitted to the ICU. Thirty-nine of 106 ward admissions had a 'do not resuscitate' status (not included in analysis). Mortality was 1.5 and 21% in patients initially admitted to a ward and the ICU, respectively. Unanticipated transfer from the ward to the ICU occurred in eight of 67 patients, resulting in higher mortality (38%, P=0.002, false negatives). Nine surviving patients admitted to the ICU for mere observation for less than 1 day were defined as false positives. Sensitivity of clinical judgement and of PIRO score (cut-off 9.5) alone or combined with clinical judgement were 0.92, 0.75 and 0.98, respectively (P<0.001). For specificity, these were 0.71, 0.56 and 0.40, respectively (P<0.001). CONCLUSION: Two-thirds of ED patients with severe sepsis were admitted to the ward, of whom ∼13% clinically deteriorated, resulting in ICU admission and higher mortality. The PIRO score adds little value over clinical judgement in guiding adequate disposition to wards or the ICU.