Do early warning track and trigger tools improve patient outcomes? A systematic synthesis without meta-analysis.

AIM: To determine the effect of Early Warning Track and Trigger Tools on patient outcomes. DESIGN: A systematic review: synthesis without meta-analysis. DATA SOURCES: Electronic databases were searched from 1 January 2013-1 August 2018 and 221 papers identified. REVIEW METHODS: A systematic review and narrative synthesis supported the identification of synthesized findings named and reported according to outcome measure. RESULTS: Five international papers representing over 74,000 patients were included in the analysis. Seven key findings were identified, the impact of NEWS on: (a) cardiopulmonary arrest; (b) mortality; (c) serious adverse events; (d) length of hospital stay; (e) hospital admissions; (f) observation frequency; and (g) Intensive/High dependency Unit admission. Papers identified statistically significant improvements in mortality, serious adverse events, hospital admissions, observation frequency, and intensive care unit/high dependency unit admission when an Early Warning Track and Trigger protocol is in use. There were conflicting results regarding length of stay and cardiopulmonary arrest data. CONCLUSION: Early Warning Track and Trigger Tools can aid recognition of deteriorating patients. Further research is required in relation to hospital length of stay and cardiopulmonary arrests. IMPACT: Early warning track and trigger tools have been implemented nationally and to a lesser degree internationally. There is evidence to suggest improved clinical outcomes following their use. Further research needs to combine the use of the National Early Warning Score with an agreed set of measured outcomes, and then subsequent study data could be combined to provide much stronger levels of evidence.