Can the Modified Early Warning Score Be Utilized as a Screening Tool to Predict Development of Sepsis-Induced Tissue Hypoperfusion in the Emergency Department?

There are currently no scoring systems employed during the emergency department (ED) intake process that reliably identify where patients are on the sepsis continuum. The Modified Early Warning Score (MEWS) is a scoring system utilized by many hospitals, for which higher scores are used to identify patients needing a greater level of care. The literature supports adopting MEWS in the ED; however, there is a paucity of literature to validate its prognostic value in the septic patient population. The purpose of this study is to assess the utility of MEWS as a screening tool that predicts the development of Sepsis-Induced Tissue Hypoperfusion (SITH) in the ED. This was a retrospective consecutive chart review conducted at a tertiary care ED. All ED charts between September and December 2012 were reviewed. Patients included in the analysis were >18 years old with a lactate order, a documented new infection, and two or more recorded SIRS criteria (P>90, RR>20, T>101 or <96.8, WBC>12,000 or <4,000) in the ED. Patients were classified into those who only met SIRS criteria and those who also met criteria for SITH (defined as a systolic blood pressure (SBP)<90 regardless of fluid administration and/or a lactate≥4mmol/L) in the ED. Discharged patient charts were excluded from analysis. Relevant data was extracted from the initial set of vital signs: SBP, heart rate (HR), respiratory rate (RR), temperature (T), oxygen saturation (SaO2), and level of consciousness (LOC). MEWS and descriptive statistics were calculated [means, 95% confidence intervals (CI)] and compared using the two sample t-test. Odds ratios (OR), 95% CI, sensitivity (SN), and specificity (SP) were also computed. Of the 29,305 charts reviewed, 1,031 were included in data analysis: 194 met SITH criteria, 837 patients only met SIRS criteria. The average MEWS between SITH and SIRS patients was significantly different [4.1 (CI: 3.831-4.369) vs 2.9 (CI: 2.791-3.009), p<0.0001). Patients with MEWS of 2 were 3.9 times more likely to develop SITH (CI: 2.0-7.3, SN: 0.935, SP: 0.213). Patients with MEWS of 3 were 3.1 times more likely to develop SITH (CI: 2.0-4.7, SN: 0.810, SP: 0.422). Patients with MEWS of 4 were 2.8 times more likely to develop SITH (CI: 2.0-4.0, SN: 0.583, SP: 0.668). Patients with MEWS of 5 were 3.0 times more likely to develop SITH (CI: 2.1-4.4, SN: 0.357, SP: 0.843). Patients with MEWS of 6 were 4.2 times more likely to develop SITH (CI: 2.6-6.7, SN: 0.220, SP: 0.937). Patients with MEWS of 7 were 4.2 times more likely to develop SITH (CI: 2.1-8.5, SN: 0.095, SP: 0.976).Tabled 1Score3210123Respiratory rate≤89-1415-2021-29>29Heart rate≤4041-5051-100101-110111-129>129Systolic BP≤7071-8081-100101-199≥200Temperature≤3535.1-3636.1-3838.1-38.5≥38.6NeurologicalAlertVoicePainUnresp Open table in a new tab The results indicate that MEWS calculated using initial vital signs were significantly higher in patients with SITH as compared to SIRS patients. Furthermore, a MEWS of 2 was found to be rather sensitive (93.5%) for ruling out development of SITH, indicating that it could be utilized as a screening tool for sepsis patients. Further studies should be conducted to validate its use during the ED intake process, and identify factors that could be used in conjunction with MEWS to further increase its sensitivity.