Sepsis 3.0

The European and American critical care societies (ESICM-SCCM) sepsis task force released their third international consensus definition of sepsis this week in the Journal of the American Medical Association (JAMA). The key points in this update are changes to the definition of sepsis, and a shift in the screening tools used.

The new task force definition of sepsis is: "life threatening organ dysfunction due to dysregulated host response to infection": a change from the previous SIRS + suspected infection definition. I think that this is, from a semantics perspective, a good decision; it moves our appreciation of sepsis away from a definition based on inflammation (a process) toward one that focuses on a clinical endpoint (organ dysfunction). The new definition drops the idea of severe sepsis (which I think is great) as any "level" of sepsis is associated with poor outcomes (mortality >10%), suggesting that all cases of sepsis should be considered severe. Both of these changes are good from a "defining sepsis" or "defining a diagnosis" perspective: the definition is more clear cut, it describes the clinical endpoint of a process, as opposed to a constellation of finding that are part of a process. The problem with the new definition, in my opinion, is primarily with the scoring tool it uses to define sepsis, the SOFA score (Sequential Organ Failure Assessment), and the evidence used to support these changes.

The current recommendation is a move from away from SIRS to SOFA/qSOFA as a diagnostic criteria. The recommendation is based upon a post hoc noted improvement in the overall precision of predicting mortality both in the ICU (AUROC 0.64 vs. 0.74/0.66) and outside of the ICU (AUROC 0.76 vs. 0.79/0.81) using SOFA/qSOFA compared to SIRS in retrospective analyses. The shift in screening tool seems great at first glance, simplified indicators and clinical acumen that yields greater predictive power - great! seems almost too good to be true- primarily because it is.

Keep in mind that this is a retrospective review of evidence. In each of the studies included the cohort examined was examined because they had an infection. Furthermore the period of time in which the studies were conducted (2008-2013) was also a time of intense interest in sepsis, a time when the current best practice was to screen patients using the SIRS criteria. The net effect of these points is that this retrospective analysis was not of undifferentiated patients; rather it was of patients with a confirmed (or suspected) infection, who in all likelihood had been screened using the SIRS criteria. The net effect is that this analysis is likely comparing the screening tools of SIRS alone to SIRS with the addition of SOFA/qSOFA. The fact that adding an additional screening tool to the process of  screening and diagnosing a patient yielded marginally better predictive value (AUROC:SIRS 0.76, SOFA 0.79, qSOFA 0.81) is not surprising.

So what does it all mean from a nursing perspective? It means that from a disease definition perspective our new "definition" of sepsis focuses on an endpoint as opposed to a process, and that it recognizes all "stages" of sepsis as bad by dropping severe, both of which I think are good changes. It also recommends a move from SIRS to qSOFA as a screening tool. From a nursing perspective, until qSOFA is endorsed by groups of emergency providers, and until it is validated prospectively, it is not likely to change practice in a meaningful way. I would suggest that appreciating the commonalities between qSOFA, SIRS, and plain old clinical acumen (suspected infection with abnormal vital signs) is the important take home message, and that from a practical perspective the process of triaging and treating patients with suspected sepsis is unlikely to change over the short term as a result of this study.

There has been a good number of different takes on the changes by the FOAMed community, with more sure to follow. I would reommend the great summaries available on RebelEM, St.Emyln's, FOAMCAST and LITFL, as well as critique by Justin Morgenstern on First10EM. Of course the original research should also be read before arriving at any conclusions, the link to the original article can be found below.

http://jama.jamanetwork.com/article.aspx?articleid=2492875