Predictive validity and internal consistency of the pre-hospital index measured on-site by physicians

Adult prehospital scoring systems: a critical review

The goal of trauma triage is to get the right patient to the right place at the right time. In an attempt to achieve this objective numerous authors have developed a variety of prehospital triage tools. Comparative evaluation to determine which of the currently developed triage tools has the greatest predictive power has been prevented mainly because of the varying definitions of major trauma. The use of small data sets and the absence of model validation techniques have also prevented the true worth of these triage tools from being accurately determined. The aim of this article is to critically appraise the major prehospital triage tools.

Current state of trauma care in China, tools to predict death and ICU admission after arrival to hospital

BACKGROUND

In China, a nationwide emergency system takes charge of pre-hospital emergency services, and it adopts a proximity principle to send trauma patients to the nearest hospitals. However, many severely injured patients have been sent to low level hospitals with no capability to treat severe trauma. Thus those patients with high probability of in-hospital death or intensive care unit (ICU) admission need to be identified in the emergency department (ED) for optimal utilisation of hospital resources and better patient outcomes. The purpose of the study was to develop a computerised tool to aid ED physicians' prediction of in-hospital death and ICU admission for trauma patients after arrival to hospital.

METHODS

We reviewed a sample of 1,299 trauma patients who had been directly sent to the ED at Kailuan Hospital, North China. After excluding those cases with incomplete data entry, information of 1,195 patients was employed for analysis. The primary outcome was severe trauma that either resulted in death in hospital or in ICU admission. We proposed to use a complementary approach to combine the Pre-Hospital Index (PHI), the Trauma Index (TI), and the Glasgow Coma Score (GCS) in a decision support system (DSS) to assess trauma and predict in-hospital death and ICU admission. The sensitivity, specificity, over-triage rate, and under-triage rate were used as measurements to compare system performances of the DSS with the three scoring tools.

RESULTS

Among the 1,195 patients, 30 (2.5%) had severe trauma. The proposed DSS showed the best sensitivity (66.7%; 95% CI: 49.8-83.6%) among all the four studied tools. The TI (sensitivity 50.0%, 95% CI: 32.2-67.8%) performed slightly better than the GCS (sensitivity 46.7%, 95% CI: 28.9-64.5%), while both the TI and GCS performed better than the PHI (sensitivity 30.0%, 95% CI: 13.5-46.5%). The performance differences between the DSS and the three extant scoring tools were statistically significant.

CONCLUSIONS

The proposed DSS outperformed the extant trauma scoring systems. It has a strong potential to help ED physicians identify severe trauma, optimally utilise hospital resources, and recommend appropriate triage and treatment strategies for trauma patients that have strong possibilities for in-hospital death and ICU admission.

Trauma Incidents Attended by Emergency Medical Services in Victoria, Australia

Introduction:

International literature describing the profile of trauma patients attended by a statewide emergency medical services (EMS) system is lacking. Most literature is limited to descriptions of trauma responses for a single emergency medical service, or to patients transported to a specific Level-1 trauma hospital. There is no Victorian or Australian literature describing the type of trauma patients transported by a state emergency medical service.

Purpose:

The purpose of this study was to define a profile of all trauma incidents attended by statewide EMS.

Methods:

A retrospective cohort study of all patient care records (PCR) for trauma responses attended by Victorian Ambulance Services for 2002 was conducted. Criteria for trauma categories were defined previously, and data were extracted from the PCRs and entered into a secure data repository for descriptive analysis to determine the trauma profile. Ethics committee approval was obtained.

Results:

There were 53,039 trauma incidents attended by emergency ambulances during the 12-month period. Of these, 1,566 patients were in physiological distress, 11,086 had a significant pattern of injury, and a further 8,931 had an identifiable mechanism of injury. The profile includes minor trauma (n = 9,342), standing falls (n = 20,511), no patient transported (n = 3,687), and deceased patients (n = 459).

Conclusions:

This is a unique analysis of prehospital trauma. It provides a baseline dataset that may be utilized in future studies of prehospital trauma care. Additionally, this dataset identifies a ten-fold difference in major trauma between the prehospital and the hospital assessments.

Triage Decisions of United Kingdom Police Firearms Officers Using a Multiple-Casualty Scenario Paper Exercise

Introduction:

British police officers authorized to carry firearms may need to make judgments about the severity of injury of individuals or the relative priority of clinical need of a group of injured patients in tactical and non-tactical situations. Most of these officers receive little or no medical training beyond basic first aid to enable them to make these clinical decisions. Therefore, the aim of this study is to determine the accuracy of triage decision-making of firearms-trained police officers with and without printed decision-support materials.

Methods:

Eighty-two police firearms officers attending a tactical medicine course (FASTAid) were recruited to the study. Data were collected using a paper-based triage exercise that contained brief, clinical details of 20 adults and 10 children. Subjects were asked to assign a clinical priority of immediate or priority 1 (P1); urgent or priority 2 (P2); delayed or priority 3 (P3); or dead, to each casualty. Then, they were provided with decision-making materials, but were not given any instruction as to how these materials should be used. Subjects then completed a second triage exercise, identical to the first, except this time using the decision-support materials.

Data were analyzed using mixed between-within subjects analysis of variance. This allowed comparisons to be made between the scores for Exercise 1 (no decision-support material) and Exercise 2 (with decision-support material). It also allowed any differences between those students with previous triage training and those without previous training to be explored.

Results:

The use of triage decision-making materials resulted in a significant increase in correct responses (p <0.001). Improvement in accuracy appears to result mainly from a reduction in the extent of under-triage. There were significant differences (p <0.05) between those who had received previous triage training and those who had not, with those having received triage training doing slightly better.

Conclusion:

It appears that significant improvements in the accuracy of triage decision-making by police firearms officers can be achieved with the use of appropriate triage decision-support materials. Training may offer additional improvements in accuracy, but this improvement is likely to be small when decision-support materials are provided. With basic clinical skills and appropriate decision-support materials, it is likely that the police officer can make accurate triage decisions in a multiple-casualty scenario or make judgments of the severity of injury of a given individual in both tactical and non-tactical situations.

Neighborhood social inequalities in road traffic injuries: the influence of traffic volume and road design

OBJECTIVES

We examined the extent to which differential traffic volume and road geometry can explain social inequalities in pedestrian, cyclist, and motor vehicle occupant injuries across wealthy and poor urban areas.

METHODS

We performed a multilevel observational study of all road users injured over 5 years (n=19,568) at intersections (n=17,498) in a large urban area (Island of Montreal, Canada). We considered intersection-level (traffic estimates, major roads, number of legs) and area-level (population density, commuting travel modes, household income) characteristics in multilevel Poisson regressions that nested intersections in 506 census tracts.

RESULTS

There were significantly more injured pedestrians, cyclists, and motor vehicle occupants at intersections in the poorest than in the richest areas. Controlling for traffic volume, intersection geometry, and pedestrian and cyclist volumes greatly attenuated the event rate ratios between intersections in the poorest and richest areas for injured pedestrians (-70%), cyclists (-44%), and motor vehicle occupants (-44%).

CONCLUSIONS

Roadway environment can explain a substantial portion of the excess rate of road traffic injuries in the poorest urban areas.

Field triage of trauma patients: improving on the Prehospital Index

The purpose of the present study was to evaluate the predictive ability of the Prehospital Index (PHI) in identifying injury severity and to develop a trauma triage scale that incorporates, along with the PHI, a subset of time independent variables to improve the predictive ability of the PHI-based triage instrument. This study included 1,291 trauma patients treated in Montreal, Canada. The developed trauma triage protocol was based on logistic regression analysis, in which the model that predicts the data best was selected by using Bayesian information criterion. The selected regression model included the variables age, body region injured, mechanism of injury, comorbidity, and PHI. This algorithm was a substantial improvement in detecting major versus non-major injuries (major injury defined based on death, intensive care unit admission, and surgery intervention) over the PHI alone (area under the receiver operating characteristic curve: 0.76 v 0.66, P <.05). Considering time independent variables could lead to better injury triage decisions.

Ineffectiveness of on-site intravenous lines: is prehospital time the culprit?

The purpose of the present study was to test the association between on-site intravenous fluid replacement and mortality in patients with severe trauma. The effect of prehospital time on this association was also evaluated. The design was that of an observational quasi-experimental study comparing 217 patients who had on-site intravenous fluid replacement (IV group) with an equal number of matched patients for whom this intervention was not performed (no-IV group). The patients were individually matched on their Prehospital Index obtained at the scene and were included in the study if they had an on-site Prehospital Index score > 3 and were transported alive to the hospital. The outcome measure of interest was mortality because of injury. The patients in the IV group had a significantly lower mean age (37 vs. 45 years; p < 0.001) and higher incidence of injuries to the head or neck (46 vs. 32%; p = 0.004), chest (34 vs. 17%; p < 0.001), and abdomen (28 vs. 12%; p < 0.001). The IV group also had a higher proportion of patients injured by motor vehicle crashes (41 vs. 27%; p = 0.003), firearms (9 vs. 2%; p = 0.001), and stabbing (20 vs. 9%; p = 0.001). The rate of extremity injuries (38 vs. 59%; p < 0.001) and falls (12 vs. 40%; p < 0.001) was lower for the IV group. In addition, the mean Injury Severity Score was significantly higher for the IV group (15 vs. 9; p < 0.001). The mortality rates for the IV and no-IV groups were 23 and 6% (p < 0.001). Logistic regression analysis showed that after adjusting for patient age, gender, Injury Severity Score, mechanism of injury, and prehospital time, the use of on-site intravenous fluid replacement was associated with a significant increase in the risk of mortality (adjusted odds ratio = 2.3; 95% confidence interval = 1.02-5.28; p = 0.04). To further evaluate the effect of prehospital time on the association between on-site IV use and mortality, the analysis was repeated separately for the following time strata: 0 to 30 minutes, 31 to 60 minutes, and >60 minutes. The adjusted odds ratios (95% confidence interval) for these strata were 1.05 (0.08-14.53; p = 0.97), 3.38 (0.84-13.62; p = 0.08), and 8.40 (1.27-54.69; p = 0.03). These results show that for prehospital times of less than 30 minutes, the use of on-site intravenous fluid replacement provides no benefit, and that for longer times, this intervention is associated with significant increases in the risk of mortality. The results of this observational study have shown that the use of on-site intravenous fluid replacement is associated with an increase in mortality risk and that this association is exacerbated by, but is not solely the result of, increased prehospital times. Our findings are consistent with the hypothesis that early intravenous fluid replacement is harmful because it disrupts the normal physiologic response to severe bleeding. Although this evidence is against the implementation of on-site intravenous fluid replacement for severely injured patients, further studies including randomized controlled trials are required to provide a definitive answer to this question.