Do physiological scoring and a novel point of care metabolic screen predict 48-h outcome in admissions from the emergency department resuscitation area?

OBJECTIVE: We aimed to compare the performance of a widely used physiological score [Modified Early Warning Score (MEWS)] and a novel metabolic score (derived from a blood gas) in predicting outcome in emergency department patients. DESIGN, SETTING AND PARTICIPANTS: We carried out a prospective observational study using a convenience sample of 200 patients presenting to the resuscitation area of an inner-city teaching hospital over 4 months. MAIN OUTCOME MEASURES: We looked primarily at whether either score predicted new organ failure at 48 h. Our secondary outcome measures were escalation of care and mortality at 48 h. RESULTS: In univariate analysis, MEWS and the metabolic score predicted 48-h organ failure [odds ratio (OR) 1.19, 95% confidence interval (CI) 1.04-1.35, P=0.009, and OR 1.34, 95% CI 1.015-1.56, P<0.001, respectively]. Both MEWS and the metabolic score predicted 48-h death (OR 1.32, 95% CI 1.02-1.71, P=0.03, and OR 1.56, 95% CI 1.18-2.06, P=0.002, respectively) in univariate analysis. Neither predicted 48-h escalation of care. The metabolic score remained statistically significant at predicting organ failure or death after controlling for MEWS parameters (OR 1.35, 95% CI 1.13-1.62, P=0.001, and OR 1.74, 95% CI 1.13-2.69, P=0.01, respectively). In contrast, MEWS was no longer associated with these outcomes; however, our study has small participant numbers. CONCLUSION: This pilot data suggest that a blood gas-derived metabolic score on emergency department arrival may be superior to MEWS at predicting organ failure and death at 48 h.