Intensive Care Medicine

, Volume 33, Issue 4, pp 667–679 | Cite as

Systematic review and evaluation of physiological track and trigger warning systems for identifying at-risk patients on the ward

  • Haiyan Gao
  • Ann McDonnell
  • David A. Harrison
  • Tracey Moore
  • Sheila Adam
  • Kathleen Daly
  • Lisa Esmonde
  • David R. Goldhill
  • Gareth J. Parry
  • Arash Rashidian
  • Christian P Subbe
  • Sheila Harvey
Systematic Review

Abstract

Objective

Physiological track and trigger warning systems (TTs) are used to identify patients outside critical care areas at risk of deterioration and to alert a senior clinician, Critical Care Outreach Service, or equivalent. The aims of this work were: to describe published TTs and the extent to which each has been developed according to established procedures; to review the published evidence and available data on the reliability, validity and utility of existing systems; and to identify the best TT for timely recognition of critically ill patients.

Design and setting

Systematic review of studies identified from electronic, citation and hand searching, and expert informants. Cohort study of data from 31 acute hospitals in England and Wales.

Measurements and results

Thirty-six papers were identified describing 25 distinct TTs. Thirty-one papers described the use of a TT, and five were studies examining the development or testing of TTs. None of the studies met all methodological quality standards. For the cohort study, outcome was measured by a composite of death, admission to critical care, ‘do not attempt resuscitation’ or cardiopulmonary resuscitation. Fifteen datasets met pre-defined quality criteria. Sensitivities and positive predictive values were low, with median (quartiles) of 43.3 (25.4–69.2) and 36.7 (29.3–43.8), respectively.

Conclusion

A wide variety of TTs were in use, with little evidence of reliability, validity and utility. Sensitivity was poor, which might be due in part to the nature of the physiology monitored or to the choice of trigger threshold. Available data were insufficient to identify the best TT.

Keywords

Systematic review Critical care Critical illness Scoring systems 

Notes

Acknowledgements

This study was funded by the UK National Health Service Research & Development Service Delivery & Organisation programme (SDO/74/2004). We thank the 31 hospitals that provided data for this analysis: Alex Larkin, Royal Oldham Hospital; Carol Tune, Royal Shrewsbury Hospital; Chris Subbe, Wrexham Maelor Hospital; Clare Bamforth, Dewsbury & District Hospital; David Goldhill, Royal London Hospital; Elizabeth Hogbin, Norfolk & Norwich University Hospital; Jackie Hogan/Stephen Murray, North Manchester Hospital; Jane Chandler/Erin Povey, Wexham Park Hospital; Jane Saunders, Bradford Royal Infirmary; Jane Viner, Torbay Hospital; Kath Daly, Guy's and St. Thomas' Hospital; Kelly Henley, James Cook University Hospital; Lindsay Green/Samantha Fox, Good Hope Hospital; Lorna Johnson, Leeds General Infirmary and St. James's University Hospital; Louise Stock, University Hospital Lewisham; Mike Heap/Kate Bray, Northern General Hospital and Royal Hallamshire Hospital; Natasha Williamson/Claire Brown, Hinchingbrooke Hospital; Pat Eden & Lee Hubbard, Royal National Orthopaedic Hospital; Paul Seymour/David Watts, Bromley Hospital; Ruth Mullett/Karen Robins, Alexandra Hospital and Worcester Royal Hospital; Sally Smith, Kent & Sussex Hospital and Maidstone Hospital; Sarah Ingleby/Chris Booth, Manchester Royal Infirmary; Sheila Adam, University College London Hospitals; Valerie Forde, University Hospitals Coventry; Wendy Watson/Julie Southwell, York Hospital; Wendy Wharton/Peter Groom, Southampton General Hospital.

Supplementary material

134_2007_532_MOESM1_ESM.doc (336 kb)
Electronic Supplementary Material (DOC 337K)

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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Haiyan Gao
    • 1
  • Ann McDonnell
    • 2
  • David A. Harrison
    • 1
  • Tracey Moore
    • 3
  • Sheila Adam
    • 4
  • Kathleen Daly
    • 5
  • Lisa Esmonde
    • 6
  • David R. Goldhill
    • 7
  • Gareth J. Parry
    • 8
  • Arash Rashidian
    • 9
  • Christian P Subbe
    • 10
  • Sheila Harvey
    • 1
  1. 1.Intensive Care National Audit & Research CentreLondon, WC1H 9HRUK
  2. 2.Faculty of Health and WellbeingSheffield Hallam UniversitySheffield, S10 2DRUK
  3. 3.School of Nursing and MidwiferyUniversity of SheffieldSheffield, S3 7NDUK
  4. 4.Intensive Care UnitUniversity College HospitalLondon, NW1 2BUUK
  5. 5.Intensive Care UnitSt. Thomas’ HospitalLondon, SE1 7EHUK
  6. 6.School of HealthcareUniversity of LeedsLeeds, LS2 9UTUK
  7. 7.AnaestheticsRoyal National Orthopaedic HospitalStanmore, Middlesex HA7 4LPUK
  8. 8.Quality Measurement & AnalysisChildren’s Hospital BostonBostonUSA
  9. 9.Department of Public Health and PolicyLondon School of Hygiene & Tropical MedicineLondon, WC1E 7HTUK
  10. 10.Thoracic MedicineWrexham Maelor HospitalWrexham, LL13 4TXUK

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