A National Early Warning Score for the NHS

Transcription

1 A National Early Warning Score for the NHS Professor Gary B Smith FRCA FRCP Centre of Postgraduate Medical Research & Education, School of Health and Social Care, Bournemouth University - from local data to national guidance GB Smith 2012 Southern Institute for Health Informatics Conference 2012 Your Data, My Data, Our Data

2 GB Smith 2012 Conflict of interest statement I am a past employee of Portsmouth Hospitals NHS Trust (PHT). PHT and The Learning Clinic Ltd (TLC) are co-developers of VitalPAC, the clinical software system used to collect the data for our early warning scoring system research. PHT has a royalty agreement with TLC to pay for the use of PHT intellectual property within the VitalPAC product. My wife is a minority shareholder in TLC. I am an unpaid research advisor to TLC. I have received reimbursement of travel expenses from TLC for attending symposia in the UK. I was a member of the Royal College of Physicians of London s National Early Warning Scoring System Development and Implementation Group

3 GB Smith 2012 Aims Review the background to early warning scoring systems Describe the local research behind the development of a validated early warning score (ViEWS) Describe the local contribution to the development of a National Early Warning Score (NEWS)

4 GB Smith 2012 Physiological measurements used to identify patient deterioration Heart/pulse rate Breathing rate Blood pressure Temperature Conscious level Oxygen saturation (S p O 2 )

5 GB Smith 2012 Early warning scoring systems Points HR (bpm) < > 130 sbp (mmhg) < > 200 RR (bpm) < > 30 Temp ( o C) < > 38.5 Neuro (AVPU) Alert Reacts to Voice Reacts or Pain Unresponsive based on work of Morgan, Williams and Wright [1997] periodic measurement of selected basic vital signs assign weighted scores to vital signs measurements on the basis of their derangement from an arbitrarily agreed normal range. aggregate score [early warning score] leads to a graded response trigger value (e.g., >3) set locally, depending upon system used.

6 GB Smith 2012 Smith et al. Resuscitation 2008; 78: Relationship between EWS, age and in-hospital mortality n = 9987

7 Variations in parameters in existing EWSs GB Smith 2012 Smith et al. Resuscitation 2008; 77:

8 Data collection and use Patient Administration System Heart rate Blood pressure Respiratory rate Oxygen saturation Temperature Conscious level Inspired oxygen Vital signs database Other data GB Smith 2012 Clinical care Audit Research

9 Receiver Operator Characteristics Curve values for 33 EWSs Hospital mortality as outcome 9987 patient episodes 9987 vital signs datasets 33 AWTTSs GB Smith 2012 Smith et al. Resuscitation 2008; 77:

10 ViEWS [VitalPAC Early Warning Score] GB Smith 2012 Prytherch et al. Resuscitation 2010; 81:

11 Early Warning Scores: comparison of performance using AUROCs AUROC Mortality at a given time interval as outcome patient episodes vital signs datasets EWS ViEWS GB Smith 2012 Prytherch et al. Resuscitation 2010; 81:

12 Validation of ViEWS or modified ViEWS Numbers (%) AUROC UK [Hospital mortality] Hospital 1 [Medicine] Hospital 2 [Medicine] Hospital 3 [Medicine] Hospitals [Emergency Surgery] Hospital 3 [Elective Surgery] USA [Hospital mortality] Medicine/Surgery CANADA [48 hour mortality] All patients Surgical patients Medical patients GB Smith 2012 Prytherch et al. Unpublished data Bleyer et al. Resuscitation 2011;82: Kellett & Kim. Resuscitation 2012; 83:

13 GB Smith 2012 Royal College of Physicians: early warning scores... There is no justification for the continued use of multiple different early warning scores to assess illness severity......the physiological assessment of all patients should be standardised across the NHS with the recording of a minimum clinical data set resulting in a NHS early warning (NEW) score......this will provide a standardised record of illness severity and urgency of need, from first assessment and throughout the patient journey......this NEW score should be familiar to all staff and should be used to trigger the most appropriate response, either in the community or in hospital......although many similar systems may exist, the development of a national system would promote clinical communication and facilitate wide adoption...

14 GB Smith 2012 Physiological measurements used to identify patient deterioration Heart/pulse rate Breathing rate Blood pressure Temperature Conscious level Oxygen saturation (S p O 2 ) Inspired gas (air or oxygen?)

15 Data collection and use Patient Administration System Heart rate Blood pressure Respiratory rate Oxygen saturation Temperature Conscious level Inspired oxygen Other data Vital signs database Cardiac arrest database Intensive care unit admission database GB Smith 2012 Clinical care Audit Research

16 ViEWS [VitalPAC Early Warning Score] Score Pulse (bpm) < > 131 Temp (ºC) < > 39.1 Systolic BP < > 250 (mm Hg) Resp rate (bpm) < > 25 AVPU A V, P or U S p O 2 < > 96 Inspired O 2 On air Any supplemental O 2 GB Smith 2012 Prytherch et al. Resuscitation 2010; 81:

17 GB Smith 2012 National Early Warning Score (NEWS) Score Pulse (bpm) < > 131 Temp (ºC) < > 39.1 Systolic BP < > 220 (mm Hg) Resp rate (bpm) < > 25 AVPU A V, P or U S p O 2 < > 96 Inspired O 2 On air Any supplemental O 2

18 NEWS and 33 other EWSs: comparison of performance GB Smith 2012 Smith et al. Submitted for publication

19 NEWS and 33 other EWSs: comparison of performance Outcome = Cardiac arrest, unanticipated intensive care unit admission or death within 24 hours of a NEWS value Early Warning Score AUROC 95% CI NEWS to Paterson to Bakir to GB Smith 2012 Smith et al. Submitted for publication

20 NEWS efficiency curve GB Smith 2012 Smith et al. Submitted for publication

21 GB Smith 2012 Comparative efficiency curves for NEWS and best of 33 EWSs % of observations at, or above, a given EWS value vital signs datasets NEWS 1 60 Paterson % of observations which were followed by cardiac arrest, unanticipated intensive care unit admission or death within 24 hours at, or above, a given EWS value

22 National Early Warning Score [NEWS] GB Smith 2012 Royal College of Physicians of London, 2012

23 GB Smith 2012 Summary Reviewed the background to early warning scoring systems Described the local research behind the development of a validated early warning score (ViEWS) Described the local contribution to the development of a National Early Warning Score (NEWS)

24 GB Smith 2012 Acknowledgements Portsmouth Hospitals NHS Trust David Prytherch Paul Schmidt Peter Featherstone Paul Meredith Nursing staff of PHT Staff of The Learning Clinic Ltd.