Among critically ill patients admitted to the ICU with a suspected infection, defining sepsis by an increase of 2 or more points in the Sequential Organ Failure Assessment score yielded greater prognostic accuracy for in-hospital mortality, compared with the quick SOFA and the systemic inflammatory response syndrome criteria, results from a large analysis showed.
“Accurate diagnostic criteria and consensus definitions have an important role in adult intensive care medicine, providing tools for research, benchmarking, performance monitoring, and accreditation,” researchers from The Australian and New Zealand Intensive Care Society Centre for Outcomes and Resource Evaluation reported in the Jan. 17, 2017 edition of JAMA. “Seymour and colleagues published data concerning the validity of a 2 or more–point change in the Sequential [Sepsis-related] Organ Failure Assessment (SOFA) score as a means of identifying sepsis among patients who are critically ill with suspected infection, assuming a SOFA of 0 for patients not known to have preexisting organ dysfunction ( JAMA. 2016; 315:762-74 ). In addition, the concept of the quick SOFA (qSOFA) score was introduced as a possible predictive tool among encounters with suspected infection outside the intensive care unit (ICU). These data were drawn from North American cohorts and a single German cohort and have not been validated externally.”
For the current study, the main outcome of interest was to evaluate the effect of an increase in SOFA score of 2 or more points, 2 or more systemic inflammatory response syndrome (SIRS) criteria, and a qSOFA score of 2 or more points measured within the first 24 hours of admission in discriminating in-hospital mortality among patients with suspected infection admitted to ICUs ( JAMA. 2017 Jan 17;317:290-300 ). A composite second outcome of interest was in-hospital mortality or an ICU length of stay of 3 days or more. To do so, the researchers retrospectively evaluated a cohort of 184,875 patients with an infection-related primary diagnosis who were admitted to 182 ICUs in Australia and New Zealand between 2000 and 2015. They applied SOFA, qSOFA, and SIRS criteria to data collected within 24 hours of ICU admission.
The mean age of the patients was 63 years, 45% were women, and the most common diagnosis was bacterial pneumonia (18%). Nearly 19% of patients died in the hospital and 56% died or experienced an ICU length of stay of at least 3 days or more. The researchers found that the SOFA score increased by 2 or more points in 90% of patients, while 87% manifested 2 or more SIRS criteria, and 54% had a qSOFA score of 2 or more points. In addition, discrimination of in-hospital mortality was significantly higher using SOFA (area under the receiving operating characteristic curve [AUROC], 0.753), compared with both SIRS criteria (AUROC, 0.589) and qSOFA (0.607); the between-group difference reached a P value of less than .001. Similar results were seen for the composite outcome of in-hospital mortality or an ICU length of stay of 3 days or more, which was higher using SOFA (AUROC, 0.736), compared with both SIRS criteria (AUROC, 0.609) and qSOFA (0.606); the between-group difference also reached a P value of less than .001.
The researchers acknowledged certain limitations of the study, including the fact that SOFA, SIRS criteria, and qSOFA could only be studied for the first 24 hours in the ICU. “Biochemical and physiological values could have come from any time within the first 24 hours of ICU admission and, as a result, could not be more accurately linked to the timing of the diagnosis of infection,” they wrote. “The SOFA score used should be considered a modification of the original because the cardiovascular component was estimated without knowledge of inotrope or vasopressor dose. The incidence of nosocomial infections and of infections in patients admitted with another diagnosis were unknown.”
Three of the seven study authors disclosed that they receive salary support from Monash University in Melbourne. The remainder reported having no financial disclosures.