Usually at some point in a rotation, I’ll end up quizzing a med student about SIRS criteria. I think it’s important to be able to memorize a few numbers that can help you make a quick decision about antibiotics, fluids, or transfer to the ICU.
However, a few investigators working on behalf of the Third International Consensus Definitions Task Force conducted a study of almost 150,000 patients have a new proposal for a “quick-sepsis” or “qSOFA” set of criteria that is more based on SOFA than SIRS.
The new criteria for qSOFA are suspected infection plus ≥2 of the following:
- Altered mental status (Glasgow Coma Scale score <15)
- Systolic blood pressure ≤100 mm Hg
- Respiratory rate ≥22/min
Compare this to the SOFA score, which is now officially considered to be more predictive than SIRS***:
- Platelet count
- Glasgow Coma Scale score
- Mean arterial pressure (MAP) or administration of vasopressors with type and dose
- Creatinine or urine output
- PaO2/FiO2 ratio and mechanical ventilation
The team also stated a new definition of septic shock: not just non-responsive to fluids, but having to be on pressors to maintain a MAP >65 mm Hg. A high lactate is also required (>2.0). They also axed the term “severe sepsis.”
***there is a A LOT of contention about whether SIRS or SOFA are “better.” My co-residents had a lively, very friendly, e-mail debate about this article showing the qSOFA was not actually that helpful for predicting mortality in the ICU. The point is that SIRS is meant to be used for risk stratification, and qSOFA is still too new for us to gauge what it is helpful for, even.
***Update, Feb. 2018: study in Ann Int Med published comparing prognostic accurary of qSOFA and SIRS criteria found that SIRS is more sensitive (=better screening tool), and that qSOFA has moderately better specificity for poor outcome.