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Examining the utility of the Hamilton early warning scores (HEWS) at triage: Retrospective pilot study in a Canadian emergency department

  • Steven Skitch (a1) (a2), Benjamin Tam (a2), Michael Xu (a3), Laura McInnis (a4), Anthony Vu (a4) and Alison Fox-Robichaud (a2)...

Abstract

Objectives

Early warning scores use vital signs to identify patients at risk of critical illness. The current study examines the Hamilton Early Warning Score (HEWS) at emergency department (ED) triage among patients who experienced a critical event during their hospitalization. HEWS was also evaluated as a predictor of sepsis.

Methods

The study population included admissions to two hospitals over a 6-month period. Cases experienced a critical event defined by unplanned intensive care unit admission, cardiopulmonary resuscitation, or death. Controls were randomly selected from the database in a 2-to-1 ratio to match cases on the burden of comorbid illness. Receiver operating characteristic (ROC) curves were used to evaluate HEWS as a predictor of the likelihood of critical deterioration and sepsis.

Results

The sample included 845 patients, of whom 270 experienced a critical event; 89 patients were excluded because of missing vitals. An ROC analysis indicated that HEWS at ED triage had poor discriminative ability for predicting the likelihood of experiencing a critical event 0.62 (95% CI 0.58-0.66). HEWS had a fair discriminative ability for meeting criteria for sepsis 0.77 (95% CI 0.72-0.82) and good discriminative ability for predicting the occurrence of a critical event among septic patients 0.82 (95% CI 0.75-0.90).

Conclusion

This study indicates that HEWS at ED triage has limited utility for identifying patients at risk of experiencing a critical event. However, HEWS may allow earlier identification of septic patients. Prospective studies are needed to further delineate the utility of the HEWS to identify septic patients in the ED.

Objectifs

Les scores de détection précoce reposent sur les signes vitaux pour le repérage des patients susceptibles de souffrir d’une maladie grave. L’étude décrite ici portait sur le score de détection précoce Hamilton Early Warning Score (HEWS), appliqué au moment du triage au service des urgences (SU) chez les patients ayant connu un événement grave durant leur hospitalisation. Le score HEWS a aussi fait l’objet d’évaluation comme indicateur prévisionnel de sepsie.

Méthode

La population à l’étude se composait de malades admis dans deux hôpitaux, sur une période de six mois. Les « cas » étaient formés de malades ayant subi un événement grave, défini comme un séjour non prévu au service des soins intensifs, la réanimation cardiorespiratoire ou la mort. Les « témoins », de leur côté, ont été choisis au hasard dans la base de données, et ce, dans un rapport de deux pour un afin d’apparier les cas selon le fardeau des maladies concomitantes. Enfin, les chercheurs se sont appuyés sur les courbes ROC (courbes caractéristiques de la performance d’un test) pour évaluer le score HEWS comme indicateur prévisionnel d’une détérioration grave et de sepsie.

Résultats

L’échantillon comptait 845 patients, dont 270 ont connu un événement grave. Quatre-vingt-neuf patients ont été écartés en raison de signes vitaux manquants. L’analyse ROC a indiqué que le score HEWS appliqué au moment du triage au SU avait une faible capacité de discrimination au regard des risques d’événements graves (0,62; [IC à 95 % : 0,58-0,66]), une capacité moyenne de discrimination au regard des critères de sepsie (0,77; [IC à 95 % : 0,72-0,82]) et une bonne capacité de discrimination au regard des risques d’événements graves chez les patients septicémiques (0,82; [IC à 95 % : 0,75-0,90]).

Conclusion

D’après les résultats de l’étude, le score HEWS appliqué au moment du triage au SU se révèle finalement peu utile dans le repérage des patients susceptibles de connaître un événement grave, bien qu’il puisse permettre la reconnaissance précoce des patients en état de septicémie. Il faudrait mener des études prospectives afin de circonscrire davantage l’utilité du score HEWS dans le repérage des patients septicémiques au SU.

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Copyright

Corresponding author

Correspondence to: Dr. Steven Skitch, Division of Emergency Medicine, McMaster University, Hamilton General Hospital, McMaster Clinic – 2nd Floor, 237 Barton Street East, Hamilton, ON L8L 2X2; Email: steven.skitch@medportal.ca

References

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1. Smith, GB, Prytherch, DR, Meredith, P, et al. The ability of the National Early Warning Score (NEWS) to discriminate patients at risk of early cardiac arrest, unanticipated intensive care unit admission, and death. Resuscitation 2013;84(4):465-470.10.1016/j.resuscitation.2012.12.016
2. McNeill, G, Bryden, D. Do either early warning systems or emergency response teams improve hospital patient survival? A systematic review. Resuscitation 2013;84(12):1652-1667.
3. Brabrand, M, Folkestad, L, Clausen, NG, et al. Risk scoring systems for adults admitted to the emergency department: a systematic review. Scand J Trauma Resusc Emerg Med 2010;18:8.
4. Alam, N, Vegting, IL, Houben, E, et al. Exploring the performance of the National Early Warning Score (NEWS) in a European emergency department. Resuscitation 2015;90:111-115.10.1016/j.resuscitation.2015.02.011
5. Groarke, JD, Gallagher, J, Stack, J, et al. Use of an admission early warning score to predict patient morbidity and mortality and treatment success. Emerg Med J 2008;25(12):803-806.
6. Silcock, DJ, Corfield, AR, Gowens, PA, et al. Validation of the National Early Warning Score in the prehospital setting. Resuscitation 2015;89:31-35.
7. Martin, CM, Priestap, F, Fisher, H, et al. A prospective, observational registry of patients with severe sepsis: the Canadian Sepsis Treatment and Response Registry. Crit Care Med 2009;37(1):81-88.
8. Gaieski, DF, Mikkelsen, ME, Band, RA, et al. Impact of time to antibiotics on survival in patients with severe sepsis or septic shock in whom early goal-directed therapy was initiated in the emergency department. Crit Care Med 2010;38(4):1045-1053.10.1097/CCM.0b013e3181cc4824
9. Chamberlain, DJ, Willis, E, Clark, R, et al. Identification of the severe sepsis patient at triage: a prospective analysis of the Australasian Triage Scale. Emerg Med J 2015;32(9):690-697.10.1136/emermed-2014-203937
10. Goulet, H, Guerand, V, Bloom, B, et al. Unexpected death within 72 hours of emergency department visit: were those deaths preventable? Crit Care 2015;19(1):1-7.
11. Keep, J, Messmer, A, Sladden, R, et al. National early warning score at emergency department triage may allow earlier identification of patients with severe sepsis and septic shock: a retrospective observational study. Emerg Med 2016;33(1):37-41.
12. Corfield, AR, Lees, F, Zealley, I, et al. Utility of a single early warning score in patients with sepsis in the emergency department. Emerg Med J 2014;31(6):482-487.10.1136/emermed-2012-202186
13. Tam, B, Xu, M, Fox-Robichaud, A. Hamilton Early Warning Score: predict, prevent and protect. Crit Care 2015;19(Suppl 1):P501.
14. Tam, B, Fox-Robichaud, A. Using a stratified Hamilton Early Warning Score (HEWS) at admission to predict critical events and workload. Toronto, ON: Critical Care Canada Forum; 2015.
15. Worster, A, Bledsoe, RD, Cleve, P, et al. Reassessing the methods of medical record review studies in emergency medicine research. Ann Emerg Med 2005;45(4):448-451.
16. Needham, DM, Scales, DC, Laupacis, A, et al. A systematic review of the Charlson Comorbidity Index using Canadian administrative databases: a perspective on risk adjustment in critical care research. J Crit Care 2005;20(1):12-19.10.1016/j.jcrc.2004.09.007
17. Bone, R, Balk, R, Cerra, F, et al. Definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. The ACCP/SCCM Consensus Conference Committee. American College of Chest Physicians/Society of Critical Care Medicine. Chest 1992;101:1644-1655.
18. Kaukonen, K-M, Bailey, M, Pilcher, D, et al. Systemic inflammatory response syndrome criteria in defining severe sepsis. NEJM 2015;372(17):1-10.
19. Sweet, D, Marsden, J, Ho, K, et al. Emergency management of sepsis: the simple stuff saves lives. B C Med J 2012;54(4):176-182.
20. Fan, J, Upadhye, S, Worster, A. Understanding receiver operating characteristic (ROC) curves. Can J Emerg Med 2006;8(1):19-20.
21. Wei, LA, Fearing, MA, Sternberg, EJ, et al. The confusion assessment method: a systematic review of current usage. J Am Geriatr Soc 2008;56(5):823-830.10.1111/j.1532-5415.2008.01674.x
22. Xu, M, Tam, B, Thabane, L, et al. A protocol for developing early warning score models from vital signs data in hospitals using ensembles of decision trees. BMJ Open 2015;5(9):e008699.
23. Dellinger, RP, Levy, MM, Rhodes, A, et al. Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock, 2012. Intensive Care Med 2013;39(2):165-228.10.1007/s00134-012-2769-8
24. Romero-Brufau, S, Huddleston, JM, Escobar, GJ, et al. Why the C-statistic is not informative to evaluate early warning scores and what metrics to use. Crit Care 2015;19(1):285.
25. Singer, M, Deutschman, CS, Seymour, CW, et al. The third international consensus definitions for sepsis and septic shock (Sepsis-3). JAMA 2016;315(8):801-810.10.1001/jama.2016.0287
26. di Martino, P, Leoli, F, Cinotti, F, et al. Improving vital sign documentation at triage: an emergency department quality improvement project. J Patient Saf 2011;7(1):26-29.

Keywords

Examining the utility of the Hamilton early warning scores (HEWS) at triage: Retrospective pilot study in a Canadian emergency department

  • Steven Skitch (a1) (a2), Benjamin Tam (a2), Michael Xu (a3), Laura McInnis (a4), Anthony Vu (a4) and Alison Fox-Robichaud (a2)...

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