title: Early warning score: a dynamic marker of severity and prognosis in patients with Gram-negative bacteraemia and sepsis.
abstract: BACKGROUND
  Early Warning Score (EWS) is a physiological composite score of six bedside vital parameters, routinely used in UK hospitals. We evaluated the prognostic ability of EWS in Gram-negative bacteraemia causing sepsis.
  
  
  METHODS
  We prospectively evaluated EWS as a marker of severity and prognosis in adult patients with Gram-negative bacteraemia. All adult patients with Gram-negative bacteraemia admitted to our tertiary Teaching hospital of the National Health Service in England were enrolled over 1 year period. The highest daily EWS score was recorded from 7 days before to 14 days after the date of onset of bacteraemia. The primary outcome was 28-day mortality.
  
  
  RESULTS
  A total of 245 consecutive adult patients with Gram-negative bacteraemia with sepsis were enrolled. On multivariate analysis, following variables were associated with death for every single unit change (odds ratio in the brackets): higher age (1.05), lower mean arterial pressure (1.03), lower serum bicarbonate (1.08), higher EWS (1.27), higher SOFA score (1.36), hospital-onset of infection (5.43) and need for vasopressor agents (16.4). EWS on day 0, 1, 2, and average 14-day score were significantly higher in patients who died by 28 days from the onset of bacteraemia [95 % CI 0.4-0.6] p < 0.001. A stepwise rise in EWS and failure of improvement in EWS by 2 points 48 h after the onset of bacteraemia were associated with poor outcome.
  
  
  CONCLUSIONS
  EWS is a simple and cost-effective bedside tool for the assessment of severity and prognosis of sepsis caused by Gram-negative bacteraemia.
authors.affiliation: Department of Infectious Diseases and Medical Microbiology, Bristol Centre for Antimicrobial Research and Evaluation, Southmead Hospital, North Bristol NHS Trust-A Teaching Trust of University of Bristol, Westbury-on-Trym, Bristol, BS10 5ND, UK. msalbur@hotmail.com.
authors.forename: Mahableshwar
authors.initials: M
authors.lastname: Albur
authors.affiliation: Department of Acute Medicine and Medical Microbiology, Southmead Hospital, North Bristol NHS Trust-A Teaching Trust of University of Bristol, Westbury-on-Trym, Bristol, BS10 5ND, UK.
authors.forename: Fergus
authors.initials: F
authors.lastname: Hamilton
authors.affiliation: Lead Public Health Microbiologist-South West of England, North Bristol NHS Trust, University of Bristol, Southmead Hospital, Westbury-on-Trym, Bristol, BS10 5ND, UK.
authors.forename: Alasdair P
authors.initials: AP
authors.lastname: MacGowan
mesh_terms: D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000175:diagnosis*; D019937:Diagnostic Techniques and Procedures; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D018805:Sepsis / Q000175:diagnosis*
keywords: Clinical outcome; Early warning score; Gram-negative bacteraemia