ABSTRACT
OBJECTIVE: Evaluate the resource-constrained, evidence-based, and outcome-driven Sacco Triage method (STM) for military-age victims of blunt, penetrating, and blast overpressure-like trauma. METHODS: STM is based on a mathematical model of resource-constrained triage. Its objective is to maximize expected survivors given constraints on transport and treatment resources. STM uses estimates of time-dependent victim survival probabilities and expected deteriorations. A respiration, pulse, and best motor response (RPM) score predicts survivability. Logistic function-generated survival probability estimates from 99,369 military-age victims were assessed using calibration and discrimination statistics. The consensus building Delphi method was used to provide aggregate expert opinion on victim deterioration rates. The models were solved using linear programming. Rule-based (not requiring software) protocols were determined using a greedy algorithm for Iraqi combat scenarios, and simulations enabled comparison of STM to the widely known Simple Triage and Rapid Treatment (START) method. RESULTS: RPM was an accurate predictor of survival probability, equivalent to the Revised Trauma Score and exceeding the Injury Severity Score. In 18 simulations, STM and STM rule-based protocols increased survivorship over START from 20% to an 18-fold increase. CONCLUSIONS: STM offers lifesaving and operational advantages for military-age victims of blunt, penetrating, and blast overpressure-like trauma.
Subject(s)
Military Medicine/methods , Models, Theoretical , Triage/methods , Wounds and Injuries/classification , Wounds and Injuries/mortality , Algorithms , Delphi Technique , Evidence-Based Medicine , Female , Humans , Logistic Models , Male , Outcome and Process Assessment, Health Care , Registries , Survival Rate , Trauma Severity Indices , Wounds and Injuries/therapyABSTRACT
BACKGROUND: Resource-constrained triage occurs when the number of trauma patients exceeds the capacity for simultaneous transport and treatment. The objective of this article is to apply a new resource-constrained triage method (denoted Sacco triage method [STM]) to victims of penetrating trauma and compare it with existing methods. METHODS: STM is a mathematical model of resource-constrained triage. Its objective is to maximize expected survivors given constraints on the timing and availability of resources. The model incorporates estimates of time-dependent victim survival probabilities based on initial assessments and expected deteriorations. For application to penetrating trauma, an "RPM" score based on respiratory rate, pulse rate, and best motor response was used to predict survivability. Logistic function-generated survival probability estimates for scene values of RPM were determined from 7,274 penetrating injury patients from the Pennsylvania Trauma Outcome Study. The Delphi Method provided expert consensus on victim deterioration rates, and the model was solved using linear programming. The accuracy of predicting survivability was assessed using calibration and discrimination statistics. STM was compared with START (Simple Triage and Rapid Treatment)-like triage methods with respect to process and outcomes (assessed by expected number of survivors in simulated resource-constrained casualty incidents). RESULTS: RPM was shown to be an accurate predictor of survival probability for penetrating trauma, equivalent to the Revised Trauma Score and exceeding that of the Injury Severity Score, as measured by calibration and discrimination statistics. In the simulations, STM had substantially more expected survivors than did current triage methods. CONCLUSIONS: Resource-constrained triage is modeled as an evidence-based, outcome-driven method (STM) that maximizes expected survivors in consideration of resources. STM offers lifesaving and operational advantages over current methods.
Subject(s)
Cause of Death , Models, Theoretical , Triage/methods , Wounds, Penetrating/classification , Wounds, Penetrating/mortality , Evidence-Based Medicine , Female , Humans , Injury Severity Score , Logistic Models , Male , Predictive Value of Tests , Probability , Sensitivity and Specificity , Survival Analysis , Wounds, Penetrating/therapyABSTRACT
OBJECTIVES: To develop a precise mathematical formulation of resource-constrained triage, denoted the Sacco triage method (STM), to develop an evidence-based application to blunt trauma, and to compare the STM with the simple triage and rapid treatment (START) method. METHODS: Resource-constrained triage is modeled mathematically as a classic resource allocation problem. The objective is to maximize expected survivors given constraints on the timing and availability of resources. The model incorporates estimates of time-dependent victim survival probabilities based on an initial assessment and expected deterioration. For application to blunt trauma, an "RPM" score, based on respiratory rate, pulse rate, and motor response, was used to predict survivability. Logistic function-generated survival probability estimates for scene values of RPM were determined from 76,459 blunt-injured patients from the Pennsylvania Trauma Outcome Study (PTOS). The Delphi method provided expert consensus on victim deterioration rates, and the model was solved using linear programming. STM was compared with START across various criteria of process and outcome. Outcome was measured by expected number of survivors in simulated resource-constrained casualty incidents. RESULTS: In this mathematical simulation, RPM was a more accurate predictor of survivability from blunt trauma than the Injury Severity Score and the Revised Trauma Score, as measured by calibration and discrimination statistics. STM resulted in greater expected survivorship than START in all simulations. CONCLUSIONS: Resource-constrained triage is modeled precisely as an evidence-based, outcome-driven method that maximizes expected survivors in consideration of resources. The lifesaving potential and operational advantages over current methods warrant scrutiny and further research.
Subject(s)
Evidence-Based Medicine/methods , Health Care Rationing/methods , Models, Theoretical , Triage/methods , Delphi Technique , Humans , Logistic Models , Outcome and Process Assessment, Health Care/methods , Programming, Linear , Survival Analysis , Trauma Severity Indices , Wounds, Nonpenetrating/classificationABSTRACT
BACKGROUND: Prehospital trauma patient field intubations and paralyzations, using neuromuscular blocking agents before emergency department respiratory and neurologic assessments are made, bias assessments and outcome evaluations using probability-of-survival models, such as TRISS and A Severity Characterization of Trauma (ASCOT). We present a newly developed "TRISS-like" probability-of-survival model for intubated blunt- and penetrating-injured patient assessment. METHODS: From a population of 51397 consecutively admitted trauma patients, this study used all 5740 (11.2% of the total injured population) intubated patients with complete data from a statewide trauma registry from October 1, 1993, to September 30, 1996. Model performance was evaluated using standard calibration and discrimination measures and z and W statistics of significance. RESULTS: The new model accurately predicted survival for blunt- and penetrating-injured intubated patients and is applicable to 11 etiologic patient populations. CONCLUSION: Study findings suggest that the new TRISS-like model should be used to assess both blunt- and penetrating-injured intubated patients. Use of this new model provides an analytical method for addressing a significant limitation of both the standard TRISS and ASCOT models, which are not applicable to intubated injured patient assessment. In addition, use of this model will complement TRISS/ASCOT assessments of nonintubated trauma patients and thus permit appropriate assessments for both intubated and nonintubated injured patient study populations.
Subject(s)
Intubation, Intratracheal , Models, Statistical , Survival Analysis , Wounds and Injuries/mortality , Adolescent , Adult , Aged , Child , Child, Preschool , Databases, Factual , Humans , Infant , Middle Aged , Pennsylvania , Probability , Registries , Trauma Severity Indices , Wounds and Injuries/classification , Wounds and Injuries/etiologyABSTRACT
This study explored the severity of injury of three groups of trauma patients triaged by different guidelines to a Level I urban trauma center. Results showed that with physician input in the triage process, patients chosen for helicopter transport to the trauma center had a significantly higher median level of injury severity than patient triaged to the trauma center without psysician involvement. The results have implications for controlling overtriage of patients to trauma centers
Subject(s)
Humans , Female , Male , Medical Care , Triage , United StatesABSTRACT
Injury severity scales of proven reliability and validity are essential for the appropriate allocation of therapeutic resources, for prediction of outcome, and for evaluation of the quantity and quality of emergencyh medical care in differing facilities and over time. Quantitation of injury severity in the field is particulary necessary. Existing scales are too imprecese to permit comparisons of management or systems of care. In this paper, the autors present the triage index, a measure of injury severity based on five simple variables observed in a design data set of 1084 patients. The triage index has been developed with state-of-the-art multivariate statistical techniques, meets the requirements of an interval ranking scale and has been both validated and assessed for interuser reliability. The triage index is proposed as a validated system of early, rapid, noninvasive, accurate patient assessment permiting appropriate matching of trauma victims with available therapeuitic resources as a means of reducing mortality and morbidity(AU)
