Contrasting qSOFA and SIRS Criteria for Early Sepsis Identification in a Veteran Population

Sepsis is a major public health concern: 10% of patients with sepsis die, and mortality quadruples with progression to septic shock.¹ Systemic inflammatory response syndrome (SIRS) criteria, originally published in 1992, are commonly used to detect sepsis, but as early as 2001, these criteria were recognized as lacking specificity.² Nonetheless, the use of SIRS criteria has persisted in practice. Sepsis was redefined in Sepsis-3 (2016) to guide earlier and more appropriate identification and treatment, which has been shown to greatly improve patient outcomes.^1,3 Key recommendations in Sepsis 3 included eliminating SIRS criteria, defining organ dysfunction by the Sequential Organ Failure Assessment (SOFA) score, and introducing the quick SOFA (qSOFA) score.¹

The qSOFA combines 3 clinical variables to provide a rapid, simple bedside score that measures the likelihood of poor outcomes, such as admission to an intensive care unit (ICU) or mortality in adults with suspected infection.^1,3 The qSOFA score is intended to aid healthcare professionals in more timely stratification of those patients who need escalated care to prevent deterioration.¹ The assessment also has been explored as a screening tool for sepsis in clinical practice; however, limited data exists concerning the comparative utility of qSOFA and SIRS in this capacity, and study results are inconsistent.^4-6

The most important attribute of a screening tool is high sensitivity, but high specificity also is desired. The qSOFA could supplant SIRS as a screening tool for sepsis if it maintained similarly high sensitivity but achieved superior specificity. Therefore, our primary objective for this study was to determine the effectiveness of qSOFA as a screening assessment for sepsis in the setting of a general inpatient medicine service by contrasting the sensitivity and specificity of qSOFA with SIRS in predicting sepsis, using a retrospective chart review design.

Methods

Administrative data from the Department of Veterans Affairs (VA) Corporate Data Warehouse were accessed via the VA Informatics and Computing Infrastructure (VINCI) and used to identify VA inpatient admissions and obtain the laboratory and vital sign data necessary to calculate SIRS, qSOFA, and SOFA scores. The data were supplemented by manual review of VA health records to obtain information that was not readily available in administrative records, including septic shock outcomes and laboratory and vital sign data obtained in the ICU. This study was approved by the institutional review board at the University of Iowa and the research and development committee at the Iowa City VA Medical Center (ICVAMC).

Patients

The study population included veterans admitted to the nonsurgical medicine unit at ICVAMC between August 1, 2014 and August 1, 2016 who were transferred to an ICU after admission; direct ICU admissions were not included as the qSOFA has been shown in studies to be more beneficial and offer better predictive validity outside the ICU. Excluding these direct admissions prevented any potential skewing of the data. To control for possible selection bias, veterans also were excluded if they transferred from another facility, were admitted under observation status, or if they had been admitted within the prior 30 days. These patients may have been more critically ill than those who presented directly to our facility and any prior treatment could affect the clinical status of the patient and assessment for sepsis at the time of presentation to the VA. Veterans were further required to have evidence of suspected infection based on manual review of the health record, which was determined by receipt of an antibiotic relevant to the empiric treatment of sepsis within 48 hours of admission.