The SIRS & qSOFA Confusion in Sepsis

Written by Salim Rezaie REBEL EM Medical Category: Infectious Disease

Background: It is well established that the rapid identification of patients with sepsis is needed in order to initiate timely care to improve morbidity and mortality. The systemic inflammatory response syndrome (SIRS) criteria have been used for some time for screening, however the sensitivity and specificity of these criteria have been brought to question based on recent evidence [2]. This may have been one of the many reasons why the Sepsis-3 task force recommended the quick sequential (Sepsis-related) organ failure assessment (qSOFA) for prediction of mortality in sepsis. qSOFA consists of low blood pressure (SBP ≤100mmhg), increased respiratory rate (≥22bpm), and altered mental status (GCS ≤14). 2 or more of these criteria indicates an increased risk of death. There have been several studies calling into question the sensitivity of this criteria. In this post, we will review a recent systematic review and meta-analysis assessing the prognostic value of qSOFA vs SIRS in adult patients with suspected infection in the ED, hospital wards, and the ICU.

What They Did:

Systematic review and meta-analysis comparing the prognostic accuracy of qSOFA vs SIRS for prediction of mortality in patients with suspected infection in the ICU, ED, or hospital wards

Outcomes:

Primary: Obtain summary estimates of diagnostic performance of qSOFA for prediction of mortality in patients with suspected infection

Secondary: Obtain summary estimates of diagnostic performance of SIRS for prediction of mortality in patients with suspected infection

Inclusion:

English language abstracts and full-text articles

Retrospective and prospective observational studies

Randomized and quasi-randomized controlled studies

Adult patients age ≥16 years with suspected infection

Conducted in the ED, hospital wards, or ICU

Application of qSOFA for prediction of mortality

Exclusion:

Studies evaluating all-cause mortality ≥30 days or uspecified follow-up periods

Case reports, case series, animal studies, pediatric studies

Studies evaluating qSOFA for a composite outcome

Results:

38 studies with >385,000 patients were included in the study

Strengths:

Used a structured criteria for the systematic review – PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy

Risk of bias was assessed by using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2)

Subgroup analyses were used in ICU patients to assess for heterogeneity of studies included

Overall confidence of pooled results was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) Tool

Comprehensive search of multiple databases with clear inclusion/exclusion criteria

Limitations:

Risk of bias in included studies due to qSOFA interpretation and patient selection

Many studies do not mention if qSOFA was calculated by providers blinded to the outcomes

Several studies only applied qSOFA to specific populations (i.e. neutropenic fever, pneumonia, etc..)

The definition of suspected infection is heterogeneous among studies

Discussion:

The authors of this paper state: “The sensitivity of qSOFA for predicting mortality was poor, and use of this tool for screening would likely miss many cases.”

It is important to remember that the addition of qSOFA to SIRS was designed as a an early warning risk stratification tool for patients with higher risk for death, not a screening tool

Performance of qSOFA varies depending on the population with which it is applied (i.e. more sensitive in ICU patients than non-ICU patients)

Author Conclusion: “qSOFA had poor sensitivity and moderate specificity for short-term mortality. The SIRS criteria had sensitivity superior to that of qSOFA, supporting their use for screening of patients and as a prompt for treatment initiation.”

Clinical Take Home Point: At this time, SIRS criteria + clinical judgment should continue to be used for screening patients outside the ICU (i.e. In the ED and Hospital Wards) while the addition of qSOFA can help predict the patients with the highest risk of deterioration and death.

References:

Fernando SM et al. Prognostic Accuracy of the Quick Sequential Organ Failure Assessment for Mortality in Patients With Suspected Infection: A Systematic Review and Meta-Analysis. Ann Intern Med 2018. PMID: 29404582 Kaukonen KM et al. Systemic Inflammatory Response Syndrome Criteria for Severe Sepsis. NEJM 2015. PMID: 26308693

For More Thoughts on This Topic Checkout:

Post Peer Reviewed By: Anand Swaminathan (Twitter: @EMSwami)