Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-22T23:59:02.340Z Has data issue: false hasContentIssue false

Is Overtriage Associated With Increased Mortality? Insights From a Simulation Model of Mass Casualty Trauma Care

Published online by Cambridge University Press:  08 April 2013

Abstract

Purpose: To examine the relationship between overtriage and critical mortality after a mass casualty incident (MCI) using a simulation model of trauma system response.

Methods: We created a discrete event simulation model of trauma system management of MCIs involving individual patient triage and treatment. Model variables include triage performance, treatment capability, treatment time, and time-dependent mortality of critically injured patients. We model triage as a variable selection process applied to a hypothetical population of critically and noncritically injured patients. Treatment capability is represented by staffed emergency department trauma bays with associated staffed operating rooms that are recycled after each use. We estimated critical and noncritical patient treatment times and time-dependent mortality rates from the trauma literature.

Results: In this simulation model, overtriage, the proportion of noncritical patients among all of those labeled as critical, has a positive, negative, or variable association with critical mortality depending on its etiology (ie, related to changes in triage sensitivity or to changes in the prevalence and total number of critical patients). In all of the modeled scenarios, the ratio of critical patients to treatment capability has a greater impact on critical mortality than overtriage level or time-dependent mortality assumption.

Conclusions: Increasing overtriage may have positive, negative, or mixed effects on critical mortality in this trauma system simulation model. These results, which contrast with prior analyses describing a positive linear relationship between overtriage and mortality, highlight the need for alternative metrics to describe trauma system response after MCIs. We explore using the relative number of critical patients to available and staffed treatment units, or the critical surge to capability ratio, which exhibits a consistent and nonlinear association with critical mortality in this model. (Disaster Med Public Health Preparedness. 2007;1(Suppl 1):S14–S24)

Type
Original Research and Critical Analysis
Copyright
Copyright © Society for Disaster Medicine and Public Health, Inc. 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Hardern, RD.Critical appraisal of papers describing triage systems. Acad Emerg Med. 1999;6:11661171.Google Scholar
2.Hoey, BA, Schwab, CW.Level I center triage and mass casualties. Clin Orthop Relat Res. 2004;422:2329.Google Scholar
3.Kluger, Y, Mayo, A, Soffer, D, Aladgem, D, Halperin, P.Functions and principles in the management of bombing mass casualty incidents: lessons learned at the Tel-Aviv Souraski Medical Center. Eur J Emerg Med. 2004;11:329334.Google Scholar
4.de Boer, J, Debacker, M.A more rational approach to medical disaster management applied retrospectively to the Enschede fireworks disaster, 13 May 2000. Eur J Emerg Med. 2003;10:117123.Google Scholar
5.Lerner, EB, Moscati, RM.The golden hour: scientific fact or medical “urban legend”? Acad Emerg Med. 2001;8:758760.Google Scholar
6.Frykberg, ER.Medical management of disasters and mass casualties from terrorist bombings: how can we cope? J Trauma. 2002;53:201212.CrossRefGoogle ScholarPubMed
7. American College of Surgeons Committee on Trauma. Resources for the Optimal Care of the Injured Patient. 1999 American College of Surgeons Web site. https://web2.facs.org/timssnet464/acspub/frontpage.cfm?product_class=trauma. Accessed August 7, 2007.Google Scholar
8.Hirshberg, A.Multiple casualty incidents: lessons from the front line. Ann Surg. 2004;239:322324.Google Scholar
9.Severance, HW.Mass-casualty victim “surge” management. Preparing for bombings and blast-related injuries with possibility of hazardous materials exposure. NC Med J. 2002;63:242246.Google Scholar
10.Rodoplu, U, Arnold, JL, Yucel, T, Tokyay, R, Ersoy, G, Cetiner, S.Impact of the terrorist bombings of the Hong Kong Shanghai Bank Corporation headquarters and the British Consulate on two hospitals in Istanbul, Turkey, in November 2003. J Trauma. 2005;59:195201.Google Scholar
11.Aylwin, CJ, Konig, TC, Brennan, NW, et alReduction in critical mortality in urban mass casualty incidents: analysis of triage, surge, and resource use after the London bombings on July 7, 2005. Lancet. 2006;368 955422192225.Google Scholar
12.Cone, DC, MacMillan, DS.Mass-casualty triage systems: a hint of science. Acad Emerg Med. 2005;12:739741.Google Scholar
13.Hirshberg, A, Stein, M, Walden, R.Surgical resource utilization in urban terrorist bombing: a computer simulation. J Trauma. 1999;47:545550.Google Scholar
14.Sacco, WJ, Navin, DM, Fiedler, KE 2nd Waddell, RK, Long, WB, Buckman, RF JrPrecise formulation and evidence-based application of resource-constrained triage. Acad Emerg Med. 2005;12:759770.Google Scholar
15.Stevenson, MD, Oakley, PA, Beard, SM, Brennan, A, Cook, AL.Triaging patients with serious head injury: results of a simulation evaluating strategies to bypass hospitals without neurosurgical facilities. Injury. 2001;32:267274.Google Scholar
16.Sampalis, JS, Denis, R, Lavoie, A, et alTrauma care regionalization: a process-outcome evaluation. J Trauma. 1999;46:565581.Google Scholar
17.Cook, L.The World Trade Center attack. The paramedic response: an insider's view. Crit Care. 2001;5:301303.Google Scholar
18.Cushman, JG, Pachter, HL, Beaton, HL.Two New York City hospitals' surgical response to the September 11, 2001, terrorist attack in New York City. J Trauma. 2003;54:147155.Google Scholar
19.Deshpande, AA, Mehta, S, Kshirsagar, NA.Hospital management of Mumbai train blast victims. Lancet. 2007;369 9562639640.Google Scholar
20.Auf der Heide, E.The importance of evidence-based disaster planning. Ann Emerg Med. 2006;47:3449.Google Scholar
21.McNeil, BJ, Weber, E, Harrison, D, Hellman, S.Use of signal detection theory in examining the results of a contrast examination: a case study using the lymphangiogram. Radiology. 1977;123:613617.Google Scholar
22.Garner, A, Lee, A, Harrison, K, Schultz, CH.Comparative analysis of multiple-casualty incident triage algorithms. Ann Emerg Med. 2001;38:541548.Google Scholar
23.Hirshberg, A, Scott, BG, Granchi, T, Wall, MJ Jr, Mattox, KL, Stein, M.How does casualty load affect trauma care in urban bombing incidents? A quantitative analysis. J Trauma. 2005;58:686695.Google Scholar
24.Avitzour, M, Libergal, M, Assaf, J, et alA multicasualty event: out-of-hospital and in-hospital organizational aspects. Acad Emerg Med. 2004;11:11021104.Google Scholar
25.Frykberg, ER.Principles of mass casualty management following terrorist disasters. Ann Surg. 2004;239:319321.Google Scholar
26.Einav, S, Feigenberg, Z, Weissman, C, et alEvacuation priorities in mass casualty terror-related events: implications for contingency planning. Ann Surg. 2004;239:304310.Google Scholar
27.Segell, GM.Terrorism: London public transport–July 7, 2005. Defence Security Anal. 2006;22:4559.Google Scholar
28.Liang, NJ, Shih, YT, Shih, FY, et alDisaster epidemiology and medical response in the Chi-Chi earthquake in Taiwan. Ann Emerg Med. 2001;38:549555.Google Scholar
29.Connelly, LG, Bair, AE.Discrete event simulation of emergency department activity: a platform for system-level operations research. Acad Emerg Med. 2004;11:1177–85.Google Scholar