Respiratory Rate as a Prehospital Triage Tool in Rural Trauma

Development and validation of risk prediction model for adverse outcomes in trauma patients

BACKGROUND

The prognosis of trauma patients is highly dependent on early medical diagnosis. By constructing a nomogram model, the risk of adverse outcomes can be displayed intuitively and individually, which has important clinical implications for medical diagnosis.

OBJECTIVE

To develop and evaluate models for predicting patients with adverse outcomes of trauma that can be used in different data availability settings in China.

METHODS

This was a retrospective prognostic study using data from 8 public tertiary hospitals in China from 2018. The data were randomly divided into a development set and a validation set. Simple, improved and extended models predicting adverse outcomes were developed, with adverse outcomes defined as in-hospital death or ICU transfer, and patient clinical characteristics, vital signs, diagnoses, and laboratory test values as predictors. The results of the models were presented in the form of nomograms, and performance was evaluated using area under the receiver operating characteristic curve (ROC-AUC), precision-recall (PR) curves (PR-AUC), Hosmer-Lemeshow goodness-of-fit test, calibration curve, and decision curve analysis (DCA).

RESULTS

Our final dataset consisted of 18,629 patients (40.2% female, mean age of 52.3), 1,089 (5.85%) of whom resulted in adverse outcomes. In the external validation set, three models achieved ROC-AUC of 0.872, 0.881, and 0.903, and a PR-AUC of 0.339, 0.337, and 0.403, respectively. In terms of the calibration curves and DCA, the models also performed well.

CONCLUSIONS

This prognostic study found that three prediction models and nomograms including the patient clinical characteristics, vital signs, diagnoses, and laboratory test values can support clinicians in more accurately identifying patients who are at risk of adverse outcomes in different settings based on data availability.

Critical hypertension in trauma patients following prehospital emergency anaesthesia: a multi-centre retrospective observational study

BACKGROUND

Critical hypertension in major trauma patients is associated with increased mortality. Prehospital emergency anaesthesia (PHEA) is performed for 10% of the most seriously injured patients. Optimising oxygenation, ventilation, and cerebral perfusion, whilst avoiding extreme haemodynamic fluctuations are the cornerstones of reducing secondary brain injury. The aim of this study was to report the differential determinants of post-PHEA critical hypertension in a large regional dataset of trauma patients across three Helicopter Emergency Medical Service (HEMS) organisations.

METHODS

A multi-centre retrospective observational study of consecutive adult trauma patients undergoing PHEA across three HEMS in the United Kingdom; 2015-2022. Critical hypertension was defined as a new systolic blood pressure (SBP) > 180mmHg within 10 min of induction of anaesthesia, or > 10% increase if the baseline SBP was > 180mmHg prior to induction. Purposeful logistical regression was used to explore variables associated with post-PHEA critical hypertension in a multivariable model. Data are reported as number (percentage), and odds ratio (OR) with 95% confidence interval (95%CI).

RESULTS

30,744 patients were attended by HEMS during the study period; 2161 received PHEA and 1355 patients were included in the final analysis. 161 (11.9%) patients had one or more new episode(s) of critical hypertension ≤ 10 min post-PHEA. Increasing age (compared with 16-34 years): 35-54 years (OR 1.76, 95%CI 1.03-3.06); 55-74 years (OR 2.00, 95%CI 1.19-3.44); ≥75 years (OR 2.38, 95%CI 1.31-4.35), pre-PHEA Glasgow Coma Scale (GCS) motor score four (OR 2.17, 95%CI 1.19-4.01) and five (OR 2.82, 95%CI 1.60-7.09), patients with a pre-PHEA SBP > 140mmHg (OR 6.72, 95%CI 4.38-10.54), and more than one intubation attempt (OR 1.75, 95%CI 1.01-2.96) were associated with post-PHEA critical hypertension.

CONCLUSION

Delivery of PHEA to seriously injured trauma patients risks haemodynamic fluctuation. In adult trauma patients undergoing PHEA, 11.9% of patients experienced post-PHEA critical hypertension. Increasing age, pre-PHEA GCS motor score four and five, patients with a pre-PHEA SBP > 140mmHg, and more than intubation attempt were independently associated with post-PHEA critical hypertension.

Predictors of post-intubation hypotension in trauma patients following prehospital emergency anaesthesia: a multi-centre observational study

BACKGROUND

Post-intubation hypotension (PIH) after prehospital emergency anaesthesia (PHEA) is prevalent and associated with increased mortality in trauma patients. The objective of this study was to compare the differential determinants of PIH in adult trauma patients undergoing PHEA.

METHODS

This multi-centre retrospective observational study was performed across three Helicopter Emergency Medical Services (HEMS) in the UK. Consecutive sampling of trauma patients who underwent PHEA using a fentanyl, ketamine, rocuronium drug regime were included, 2015-2020. Hypotension was defined as a new systolic blood pressure (SBP) < 90 mmHg within 10 min of induction, or > 10% reduction if SBP was < 90 mmHg before induction. A purposeful selection logistic regression model was used to determine pre-PHEA variables associated with PIH.

RESULTS

During the study period 21,848 patients were attended, and 1,583 trauma patients underwent PHEA. The final analysis included 998 patients. 218 (21.8%) patients had one or more episode(s) of hypotension ≤ 10 min of induction. Patients > 55 years old; pre-PHEA tachycardia; multi-system injuries; and intravenous crystalloid administration before arrival of the HEMS team were the variables significantly associated with PIH. Induction drug regimes in which fentanyl was omitted (0:1:1 and 0:0:1 (rocuronium-only)) were the determinants with the largest effect sizes associated with hypotension.

CONCLUSION

The variables significantly associated with PIH only account for a small proportion of the observed outcome. Clinician gestalt and provider intuition is likely to be the strongest predictor of PIH, suggested by the choice of a reduced dose induction and/or the omission of fentanyl during the anaesthetic for patients perceived to be at highest risk.

Interest of the MGAP score on in-hospital trauma patients: Comparison with TRISS, ISS and NISS scores

Trauma scoring systems were created to predict mortality and enhance triage capabilities. However, efficacy of scoring systems to predict mortality and accuracy of originally reported severity thresholds remains uncertain. A single-center, retrospective study was conducted at University of Virginia (UVA), an American College of Surgeons verified Level I trauma center. We compared four scoring systems: MGAP (Mechanism, Glasgow Coma Scale, Age, and arterial pressure), Injury Severity Score (ISS), New Injury Severity Score (NISS), and Trauma Related Injury Severity Score (TRISS) to predict in-hospital mortality and disposition from the emergency department to higher acuity level of care including mortality (i.e. operating room, intensive care unit, morgue) versus standard floor admission using area under the curve (AUC) for receiver operating characteristic analysis. Second, we examined sensitivity of these scores at standard thresholds to determine if adjustments were needed to minimize under-triage (sensitivity ≥95%). TRISS was the best predictor of mortality in a cohort of n = 16,265 with AUC of 0.920 (95% CI: 0.911-0.929, p<0.0001), followed by MGAP with AUC of 0.900 (95% CI: 0.889-0.911, p<0.0001), and finally ISS and NISS (0.830 (95% CI: 0.814-0.847) and 0.827 (95% CI: 0.809-0.844) respectively). NISS was the best predictor of high acuity disposition with an AUC of 0.729 (95% CI: 0.721-0.736, p<0.0001), followed by ISS with AUC of 0.714 (95% CI: 0.707-0.722, p<0.0001), and finally TRISS and MGAP (0.673 (95% CI: 0.665-0.682) and 0.613 (95% CI: 0.604-0.621) respectively (p<0.0001). At historic thresholds, no scoring system displayed adequate sensitivity to predict mortality, with values ranging from 73% for ISS to 80% for NISS. In conclusion, in the reported study cohort, TRISS was the best predictor of mortality while NISS was the best predictor of high acuity disposition. We also stress updating scoring system thresholds to achieve ideal sensitivity, and investigating how scoring systems derived to predict mortality perform when predicting indicators of morbidity such as disposition from the emergency department.

Developing a translational triage research tool: part two-evaluating the tool through a Delphi study among experts

Background

There are different prehospital triage systems, but no consensus on what constitutes the optimal choice. This heterogeneity constitutes a threat in a mass casualty incident in which triage is used during multiagency collaboration to prioritize casualties according to the injuries’ severity. A previous study has confirmed the feasibility of using a Translational Triage Tool consisting of several steps which translate primary prehospital triage systems into one. This study aims to evaluate and verify the proposed algorithm using a panel of experts who in their careers have demonstrated proficiency in triage management through research, experience, education, and practice.

Method

Several statements were obtained from earlier reports and were presented to the expert panel in two rounds of a Delphi study.

Results

There was a consensus in all provided statements, and for the first time, the panel of experts also proposed the manageable number of critical victims per healthcare provider appropriate for proper triage management.

Conclusion

The feasibility of the proposed algorithm was confirmed by experts with some minor modifications. The utility of the translational triage tool needs to be evaluated using authentic patient cards used in simulation exercises before being used in actual triage scenarios.

A translational triage research development tool: standardizing prehospital triage decision-making systems in mass casualty incidents

Background

There is no global consensus on the use of prehospital triage system in mass casualty incidents. The purpose of this study was to evaluate the most commonly used pre-existing prehospital triage systems for the possibility of creating one universal translational triage tool.

Methods

The Rapid Evidence Review consisted of (1) a systematic literature review (2) merging and content analysis of the studies focusing on similarities and differences between systems and (3) development of a universal system.

Results

There were 17 triage systems described in 31 eligible articles out of 797 identified initially. Seven of the systems met the predesignated criteria and were selected for further analysis. The criteria from the final seven systems were compiled, translated and counted for in means of 1/7’s. As a product, a universal system was created of the majority criteria.

Conclusions

This study does not create a new triage system itself but rather identifies the possibility to convert various prehospital triage systems into one by using a triage translational tool. Future research should examine the tool and its different decision-making steps either by using simulations or by experts’ evaluation to ensure its feasibility in terms of speed, continuity, simplicity, sensitivity and specificity, before final evaluation at prehospital level.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-021-00932-z.

Trauma models to identify major trauma and mortality in the prehospital setting

BACKGROUND

Patients with major trauma might benefit from treatment in a trauma centre, but early identification of major trauma (Injury Severity Score (ISS) over 15) remains difficult. The aim of this study was to undertake an external validation of existing prognostic models for injured patients to assess their ability to predict mortality and major trauma in the prehospital setting.

METHODS

Prognostic models were identified through a systematic literature search up to October 2017. Injured patients transported by Emergency Medical Services to an English hospital from the Trauma Audit and Research Network between 2013 and 2016 were included. Outcome measures were major trauma (ISS over 15) and in-hospital mortality. The performance of the models was assessed in terms of discrimination (concordance index, C-statistic) and net benefit to assess the clinical usefulness.

RESULTS

A total of 154 476 patients were included to validate six previously proposed prediction models. Discriminative ability ranged from a C-statistic value of 0·602 (95 per cent c.i. 0·596 to 0·608) for the Mechanism, Glasgow Coma Scale, Age and Arterial Pressure model to 0·793 (0·789 to 0·797) for the modified Rapid Emergency Medicine Score (mREMS) in predicting in-hospital mortality (11 882 patients). Major trauma was identified in 52 818 patients, with discrimination from a C-statistic value of 0·589 (0·586 to 0·592) for mREMS to 0·735 (0·733 to 0·737) for the Kampala Trauma Score in predicting major trauma. None of the prediction models met acceptable undertriage and overtriage rates.

CONCLUSION

Currently available prehospital trauma models perform reasonably in predicting in-hospital mortality, but are inadequate in identifying patients with major trauma. Future research should focus on which patients would benefit from treatment in a major trauma centre.

Tree-based algorithm for prehospital triage of polytrauma patients

BACKGROUND

There is a need for better allocation of medical resources in polytrauma, by optimizing both the over and undertriage rates. The goal of this study is to provide a new working definition for polytrauma based on the prediction of the need for specialized trauma care.

METHODS

This is a prospective, observational study, performed in a specialized trauma center in Paris. All consecutive patients admitted for a trauma at a major trauma center in Paris were included in the study. The primary outcome was the need for specialized trauma care as defined by the North American consensus. The explanatory variables included basic variables collected on scene. The modeling approach relied on recursive partitioning based decision trees. Its prediction performance was evaluated both internally and externally on a validation cohort, and compared to the MGAP (Mechanism, Glasgow coma scale, Age and Arterial pressure) score.

MEASUREMENTS AND MAIN RESULTS

1160 patients were included in the analysis over a 3-year period (2012-2014), out of which 41% needed specialized trauma care as defined by the recent US guidelines. The decision tree outperformed the MGAP and reached an area under the receiver operating characteristic curve of 0.82 [0.79-0.84]. This optimal decision rule was associated with a sensitivity of 0.94 [0.92-0.96], a specificity of 0.48 [0.44-0.52]. A conservative decision rule (refer to a trauma center all patient with a predicted probability ≥0.34) would result in an undertriage rate of 5.7% and an overtriage of 52.3% (respectively 7% and 64% in the validation cohort).

CONCLUSIONS

Our tree-based decision algorithm is a user-friendly and reliable alternative to the preexisting scores, which offers good performance to predict the need for specialized trauma care.

Validation of a novel prediction model for early mortality in adult trauma patients in three public university hospitals in urban India

BACKGROUND

Trauma is one of the top threats to population health globally. Several prediction models have been developed to supplement clinical judgment in trauma care. Whereas most models have been developed in high-income countries the majority of trauma deaths occur in low- and middle-income countries. Almost 20 % of all global trauma deaths occur in India alone. The aim of this study was to validate a basic clinical prediction model for use in urban Indian university hospitals, and to compare it with existing models for use in early trauma care.

METHODS

We conducted a prospective cohort study in three hospitals across urban India. The model we aimed to validate included systolic blood pressure and Glasgow coma scale. We compared this model with three additional models, which all have been designed for use in bedside trauma care, and two single variable models based on systolic blood pressure and Glasgow coma scale respectively. The outcome was early mortality, defined as death within 24 h from the time when vital signs were first measured. We compared the models in terms of discrimination, calibration, and potential clinical consequences using decision curve analysis. Multiple imputation was used to handle missing data. Performance measures are reported using their median and inter-quartile range (IQR) across imputed datasets.

RESULTS

We analysed 4440 patients, out of which 1629 were used as an updating sample and 2811 as a validation sample. We found no evidence that the basic model that included only systolic blood pressure and Glasgow coma scale had worse discrimination or potential clinical consequences compared to the other models. A model that also included heart had better calibration. For the model with systolic blood pressure and Glasgow coma scale the discrimination in terms of area under the receiver operating characteristics curve was 0.846 (IQR 0.841-0.849). Calibration measured by estimating a calibration slope was 1.183 (IQR 1.168-1.202). Decision curve analysis revealed that using this model could potentially result in 45 fewer unnecessary surveys per 100 patients.

CONCLUSIONS

A basic clinical prediction model with only two parameters may prove to be a feasible alternative to more complex models in contexts such as the Indian public university hospitals studied here. We present a colour-coded chart to further simplify the decision making in early trauma care.

An observational study of adults seeking emergency care in Cambodia

Objective

To describe the characteristics and chief complaints of adults seeking emergency care at two Cambodian provincial referral hospitals.

Methods

Adults aged 18 years or older who presented without an appointment at two public referral hospitals were enrolled in an observational study. Clinical and demographic data were collected and factors associated with hospital admission were identified. Patients were followed up 48 hours and 14 days after presentation.

Findings

In total, 1295 hospital presentations were documented. We were able to follow up 85% (1098) of patients at 48 hours and 77% (993) at 14 days. The patients’ mean age was 42 years and 64% (823) were females. Most arrived by motorbike (722) or taxi or tuk-tuk (312). Most common chief complaints were abdominal pain (36%; 468), respiratory problems (15%; 196) and headache (13%; 174). Of the 1050 patients with recorded vital signs, 280 had abnormal values, excluding temperature, on arrival. Performed diagnostic tests were recorded for 539 patients: 1.2% (15) of patients had electrocardiography and 14% (175) had diagnostic imaging. Subsequently, 783 (60%) patients were admitted and 166 of these underwent surgery. Significant predictors of admission included symptom onset within 3 days before presentation, abnormal vital signs and fever. By 14-day follow-up, 3.9% (39/993) of patients had died and 19% (192/993) remained functionally impaired.

Conclusion

In emergency admissions in two public hospitals in Cambodia, there is high admission-to-death ratio and limited application of diagnostic techniques. We identified ways to improve procedures, including better documentation of vital signs and increased use of diagnostic techniques.

Predicting early mortality in adult trauma patients admitted to three public university hospitals in urban India: a prospective multicentre cohort study

BACKGROUND

In India alone, more than one million people die yearly due to trauma. Identification of patients at risk of early mortality is crucial to guide clinical management and explain prognosis. Prediction models can support clinical judgement, but existing models have methodological limitations. The aim of this study was to derive a vital sign based prediction model for early mortality among adult trauma patients admitted to three public university hospitals in urban India.

METHODS

We conducted a prospective cohort study of adult trauma patients admitted to three urban university hospitals in India between October 2013 and January 2014. The outcome measure was mortality within 24 hours. We used logistic regression with restricted cubic splines to derive our model. We assessed model performance in terms of discrimination, calibration, and optimism.

RESULTS

A total of 1629 patients were included. Median age was 35, 80% were males. Mortality between admission and 24 hours was 6%. Our final model included systolic blood pressure, heart rate, and Glasgow coma scale. Our model displayed good discrimination, with an area under the receiver operating characteristics curve (AUROCC) of 0.85. Predicted mortality corresponded well with observed mortality, indicating good calibration.

CONCLUSION

This study showed that routinely recorded systolic blood pressure, heart rate, and Glasgow coma scale predicted early hospital mortality in trauma patients admitted to three public university hospitals in urban India. Our model needs to be externally validated before it can be applied in the clinical setting.

Prehospital Mass-Casualty Triage Training—Written Versus Moulage Scenarios: How Much Do EMS Providers Retain?

Introduction

The aim of this study was to assess the effectiveness of written and moulage scenarios using video instruction for mass-casualty triage by evaluating skill retention at six months post intervention.

Methods

Prehospital personnel were instructed in the START method of mass-casualty triage using a video. Moulage and written testing were completed by each participant immediately after instruction and at six months post instruction.

Results

There was a significant decrease in performance between initial and six-month testing, indicating skill decay and loss of retention of triage skills after an extended nonuse period. There were no statistically significant differences between written and moulage testing results at either initial testing or at six months. Prior skill level did not influence test performance on the type of testing conducted or long-term retention of triage skills.

Conclusion

These data confirm the skill deterioration associated with an infrequently used triage method. Further research to more precisely define triage criteria, as well as the ability to apply the criteria in a clinical setting and to rapidly identify patients at risk for morbidity/mortality is needed.

RisaviBL, TerrellMA, LeeW, HolstenDLJr. Prehospital mass-casualty triage training—written versus moulage scenarios: how much do EMS providers retain?. Prehosp Disaster Med. 2013;28(3):1-6.

Usage of documented pre-hospital observations in secondary care: a questionnaire study and retrospective comparison of records

BACKGROUND

The patient handover is important for the safe transition from the pre-hospital setting to secondary care. The loss of critical information about the pre-hospital phase may impact upon the clinical course of the patient.

METHODS

University Hospital Emergency Care registrars answered a questionnaire about how they perceive clinical documentation from the ambulance services. We also reviewed patient records retrospectively, to investigate to what extent eight selected parameters were transferred correctly to hospital records by clinicians. Only parameters outside the normal range were selected.

RESULTS

The registrars preferred a verbal handover with hand-written pre-hospital reports as the combined source of clinical information. Scanned report forms were infrequently used. Information from other doctors was perceived as more important than the information from ambulance crews. Less than half of the selected parameters in pre-hospital notes were transferred to hospital records, even for parameters regarded as important by the registrars. Abnormal vital signs were not transferred as often as mechanism of injury, medication administered and immobilisation of trauma patients.

CONCLUSIONS

Data on pre-hospital abnormal vital signs are frequently not transferred to the hospital admission notes. This information loss may lead to suboptimal care.

UK triage--an improved tool for an evolving threat

INTRODUCTION

A key challenge at a major incident is to quickly identify those casualties most urgently needing treatment in order to survive - triage. The UK Triage Sieve (TS) advocated by the Major Incident Medical Management (MIMMS) Course categorises casualties by ability to walk, respiratory rate (RR) and heart rate (HR) or capillary refill time. The military version (MS) includes assessment of consciousness. We tested whether the MS better predicts need for life-saving intervention in a military trauma population. Ideal HR, RR and Glasgow Coma Score (GCS) thresholds were calculated.

METHODS

A gold standard Priority 1 casualty was defined using resource-based criteria. Pre-hospital data from a military trauma database allowed calculation of triage category, which was compared with this standard, and presented as 2×2 tables. Sensitivity and specificity of each physiological parameter was calculated over a range of values to identify the ideal cut-offs.

RESULTS

A gold standard could be ascribed in 1657 cases. In 1213 both the MS and TS could ascribe a category. MS was significantly more sensitive than TS (59% vs 53%, p<0.001) with similar specificity (89 vs 88%). Varying the limits for each parameter allowed some improvements in sensitivity (70-80%) but specificity dropped rapidly.

DISCUSSION

Previous studies support the inclusion of GCS assessment for blunt as well as penetrating trauma. Optimising the physiological cut-offs increased sensitivity in this sample to only 71% - a Sieve based purely on physiological parameters may not be capable of an acceptable level of sensitivity.

CONCLUSIONS

The MS is more sensitive than the TS. Major incident planners utilising the Sieve should consider adopting the military version as their first line triage tool. If validated, altering the HR and RR thresholds may further improve the tool.

Nurses as first responders in a mass casualty: are you prepared?

A mass casualty event is a situation in which the need for medical care and resources, including personnel, exceeds that which is available. As the largest component of the health care workforce, nurses represent a significant resource that can be called on to act as first responders during a mass casualty. However, current education and national guidelines fail to provide specific instruction on pre-hospital nursing considerations and interventions. This article provides evidence-based guidelines designed for nurses to use when acting as first responders during a disaster and presents recommendations for future nursing practice related to mass casualty events.

Trained Lay First Responders Reduce Trauma Mortality: A Controlled Study of Rural Trauma in Iraq

Introduction:

Recent studies demonstrate that early, in-field, basic life support by paramedics improves trauma survival where prehospital transport times are long. So far, no case-control studies of the effect of layperson trauma first responders have been reported. It was hypothesized that trained layperson first responders improve trauma outcomes where prehospital transit times are long.

Methods:

A rural prehospital trauma system was established in the mine and war zones in Iraq, consisting of 135 paramedics and 7,000 layperson trauma first responders in the villages. In a non-randomized clinical study, the outcomes of patients initially managed in-field by first-responders were compared to patients not receiving first-responder support.

Results:

The mortality rate was significantly lower among patients initially managed in-field by first responders (n = 325) compared to patients without first-responder support (n = 1,016), 9.8% versus 15.6%, 95% CI = 1.3−10.0%.

Conclusions:

Trained layperson first responders improve trauma outcomes where prehospital evacuation times are long. This finding demonstrates that simple interventions done early—by any type of trained care provider—are crucial for trauma survival. Where the prevalence of severe trauma is high, trauma first-responders should be an integral element of the trauma system.

Bridging the Gap: Building Local Resilience and Competencies in Remote Communities

This keynote address will focus on the potential to reduce the increasing gap between rich and poor countries. This critical gap only can be bridged if we systematically replace the expensive and reactive international disaster post-hoc operations by systematic, long-term, proactive efforts to increase the local capacity to master everyday accidents and emergencies as well as empower the local preparedness for major events such as natural and technological events. If we really wish to strengthen local preparedness and competencies in remote communities in lowand middle-income countries (LMIC, “the South”), we must systematically share knowledge and skills through scientifically proven training programs aimed at such impoverished, still densely populated regions in the South. Such local training represents a sustainable, long-term action to build emergency medical capacity into the local population and the health workers, as opposed to only relying on expensive foreign relief that arrive too late, is cost ineffective, and most often responds to spectacular disasters. Building local competence also strengthens local resilience (Table 1).

Prehospital trauma care reduces mortality. Ten-year results from a time-cohort and trauma audit study in Iraq

BACKGROUND

Blunt implementation of Western trauma system models is not feasible in low-resource communities with long prehospital transit times. The aims of the study were to evaluate to which extent a low-cost prehospital trauma system reduces trauma deaths where prehospital transit times are long, and to identify specific life support interventions that contributed to survival.

METHODS

In the study period from 1997 to 2006, 2,788 patients injured by land mines, war, and traffic accidents were managed by a chain-of-survival trauma system where non-graduate paramedics were the key care providers. The study was conducted with a time-period cohort design.

RESULTS

37% of the study patients had serious injuries with Injury Severity Score ≥ 9. The mean prehospital transport time was 2.5 hours (95% CI 1.9 - 3.2). During the ten-year study period trauma mortality was reduced from 17% (95% CI 15 -19) to 4% (95% CI 3.5 - 5), survival especially improving in major trauma victims. In most patients with airway problems, in chest injured, and in patients with external hemorrhage, simple life support measures were sufficient to improve physiological severity indicators.

CONCLUSION

In case of long prehospital transit times simple life support measures by paramedics and lay first responders reduce trauma mortality in major injuries. Delegating life-saving skills to paramedics and lay people is a key factor for efficient prehospital trauma systems in low-resource communities.

In 'big bang' major incidents do triage tools accurately predict clinical priority?: a systematic review of the literature

INTRODUCTION

The term "big bang" major incidents is used to describe sudden, usually traumatic,catastrophic events, involving relatively large numbers of injured individuals, where demands on clinical services rapidly outstrip the available resources. Triage tools support the pre-hospital provider to prioritise which patients to treat and/or transport first based upon clinical need. The aim of this review is to identify existing triage tools and to determine the extent to which their reliability and validity have been assessed.

METHODS

A systematic review of the literature was conducted to identify and evaluate published data validating the efficacy of the triage tools. Studies using data from trauma patients that report on the derivation, validation and/or reliability of the specific pre-hospital triage tools were eligible for inclusion.Purely descriptive studies, reviews, exercises or reports (without supporting data) were excluded.

RESULTS

The search yielded 1982 papers. After initial scrutiny of title and abstract, 181 papers were deemed potentially applicable and from these 11 were identified as relevant to this review (in first figure). There were two level of evidence one studies, three level of evidence two studies and six level of evidence three studies. The two level of evidence one studies were prospective validations of Clinical Decision Rules (CDR's) in children in South Africa, all the other studies were retrospective CDR derivation, validation or cohort studies. The quality of the papers was rated as good (n=3), fair (n=7), poor (n=1).

CONCLUSION

There is limited evidence for the validity of existing triage tools in big bang major incidents.Where evidence does exist it focuses on sensitivity and specificity in relation to prediction of trauma death or severity of injury based on data from single or small number patient incidents. The Sacco system is unique in combining survivability modelling with the degree by which the system is overwhelmed in the triage decision system. The practicalities, training implications, performance characteristics and reliance on computer technology during a mass casualty incident require further evaluation.

Prognostic models for the early care of trauma patients: a systematic review

BACKGROUND

Early identification of major trauma may contribute to timely emergency care and rapid transport to an appropriate health-care facility. Several prognostic trauma models have been developed to improve early clinical decision-making.

METHODS

We systematically reviewed models for the early care of trauma patients that included 2 or more predictors obtained from the evaluation of an adult trauma victim, investigated their quality and described their characteristics.

RESULTS

We screened 4,939 records for eligibility and included 5 studies that derivate 5 prognostic models and 9 studies that validate one or more of these models in external populations. All prognostic models intended to change clinical practice, but none were tested in a randomised clinical trial. The variables and outcomes were valid, but only one model was derived in a low-income population. Systolic blood pressure and level of consciousness were applied as predictors in all models.

CONCLUSIONS

The general impression is that the models perform well in predicting survival. However, there are many areas for improvement, including model development, handling of missing data, analysis of continuous measures, impact and practicality analysis.

Physiologically focused triage criteria improve utilization of pediatric surgeon-directed trauma teams and reduce costs

INTRODUCTION

Pediatric surgeon-directed trauma teams (STTs) provide lifesaving treatment but at a high cost. We used physiologically based criteria to improve STT utilization.

METHODS

We reviewed 152 consecutive STT activations at one center, comparing standard and physiologically focused criteria and 24-hour hospital costs/charges for overtriaged patients vs level 2 (emergency department managed) blunt trauma patients matched for age, Injury Severity Score (ISS), and necessity for operation.

RESULTS

Our cohort (73.0% male; 86.8% blunt; median age, 8.0 [interquartile range, 4.0-14.0] years) had 10 deaths (6.6%) and 18 (11.8%) emergent operations. Twenty-nine patients met neither standard nor physiologic criteria (group 1), 25 met standard but not physiologic criteria (overtriaged, group 2), and 98 met physiologic criteria (group 3). Group 3 had higher median ISS (19.0 [10.0-33.0] vs 10.0 [4.0-17.0] and 5.5 [5.0-16.75] for groups 1 and 2, P = .001), more intensive care unit admissions (67.2% vs 31.0% and 52.0%, P = .001), longer hospitalization (5.0 [3.0-9.25] days vs 3.0 [1.0-5.0] and 4.0 [2.0-5.0] days, P = .002), and all patients who died or required emergent operation (P < .001). Physiologic criteria maintained 100% sensitivity but improved specificity (49.2% vs 23.0%). Overtriaged patients (n = 18) had 78.2% higher charges ($4700; 95% confidence interval, 13.3%-180.1%; P = .013) and 53.4% higher costs ($800; 95% confidence interval, 1.8%-131.2%; P = .041) than level 2 patients (n = 259) after adjusting for age, ISS, and need for operation, largely because of computed tomography and emergency department charges (66% of overtriaged charges).

CONCLUSIONS

Physiologic STT activation criteria would have saved 25 activations, $20,000 in costs, and $120,000 in charges annually without compromising patient safety.

[Utility of the detection of nasal flaring in the assessment of severity of dyspnea]

OBJECTIVE

To determine if the presence of nasal flaring is indicative of severe respiratory insufficiency.

METHODS

Prospective observational study of patients consulting in the Emergency Department because of dyspnea whose triage level is II or III in the Spanish Triage System (MAT-SET). Vital signs, SpO2, arterial blood gases and nasal flaring presence were recorded, as well as the need for hospital admission and length of hospital stay. Data are presented as median (25-75th percentile).

RESULTS

A total of 43 patients were analyzed (70% men, aged 77 (67-82) years), 7 of whom showed nasal flaring. Those having flaring had higher respiratory rate (36 (34-40) vs. 25 (20-28) vs., p=0.001) and were more acidotic (pH 7.34 [7.23-7.40] vs. 7.42 [7.39-7.46] vs., p=0.03) than patients without this sign. There were no differences between groups in SpO2, PaCO2, heart rate and arterial pressure. There were no differences in the rate of hospital admission-(6 patients [85.7%] in nasal flaring group vs 29 patients [80.5%] in the non nasal flaring group [p=0,06], or in the length of the hospital stay-3 days [1-16] in nasal flaring group vs. 6 days [1-10] in the non nasal flaring group, p=0.6). All patients with nasal flaring had tachypnea.

CONCLUSION

In our study, nasal flaring does not indicate severity in dyspneic patients in spite of its association with tachypnea and acidosis.

Effect of the rural rescue system on reducing the mortality rate of landmine victims: a prospective study in Ilam Province, Iran

BACKGROUND

In several Iranian provinces, there are large numbers of landmines that threaten the lives of many civilians. Ilam is one of the most polluted areas with 1,086 injuries from landmines between 1989 to 1999, with an overall mortality rate of 36.4%. A remarkable number of deaths occurred before the injured were conveyed to the hospital. In this survey, the effects of on trauma outcome of the use of prehospital trauma life support provided by trained paramedics and rural health workers as first responders were examined.

METHODS

In an interventional, prospective study, 4,834 persons (general physicians, nurses, rural health workers, and emergency technicians, high- and low-educated people, layperson villagers, and nomads) were trained in one level of advanced (for general physicians and nurses) and four levels of basic life support courses during two years (2000-2001). Following the training, the data from 288 landmine victims who were referred to the main hospital in Ilam (trauma center) were registered prospectively (2001-2005). The effects of prehospital trauma life support training were assessed by using the Injury Severity Scale (ISS) score and prehospital physiologic severity (PSS) score.

RESULTS

There were 288 injuries from landmines in the Mehran region between 2002 and 2005. The mean ISS score was 20.3 with a median of 13. Forty percent were severely injured with an ISS score >15. Of the injured who received prehospital care at the Mehran Emergency Center, the mean value of the PSS scores was 6.40, which improved to 7.43 in the hospital (p = 0.01; 95% CI for difference -0.72 to -0.45), in comparison with 5.97 in the injured who were conveyed to Ilam Hospital directly (mean of ISS was approximately equal in both groups). The total mortality rate was 27% between 2001 and 2005.

CONCLUSIONS

Prehospital educations and training help improve PSS scores and reduce the death toll of landmine accidents in the remote areas.

Trauma Triage: Concepts in Prehospital Trauma Care

This report examines the efficacy of current trauma triage rules to determine the exigency of field care and transport of severely injured patients from a variety of medical populations.

Precision of field triage in patients brought to a trauma centre after introducing trauma team activation guidelines

BACKGROUND

Field triage is important for regional trauma systems providing high sensitivity to avoid that severely injured are deprived access to trauma team resuscitation (undertriage), yet high specificity to avoid resource over-utilization (overtriage). Previous informal trauma team activation (TTA) at Ulleval University Hospital (UUH) caused imprecise triage. We have analyzed triage precision after introduction of TTA guidelines.

METHODS

Retrospective analysis of 7 years (2001-07) of prospectively collected trauma registry data for all patients with TTA or severe injury, defined as at least one of the following: Injury Severity Score (ISS) > 15, proximal penetrating injury, admitted ICU > 2 days, transferred intubated to another hospital within 2 days, dead from trauma within 30 days. Interhospital transfers to UUH and patients admitted by non-healthcare personnel were excluded. Overtriage is the fraction of TTA where patients are not severely injured (1-positive predictive value); undertriage is the fraction of severely injured admitted without TTA (1-sensitivity).

RESULTS

Of the 4,659 patients included in the study, 2,221 (48%) were severely injured. TTA occurred 4,440 times, only 2,002 of which for severely injured (overtriage 55%). Overall undertriage was 10%. Mechanism of injury was TTA criterion in 1,508 cases (34%), of which only 392 were severely injured (overtriage 74%). Paramedic-manned prehospital services provided 66% overtriage and 17% undertriage, anaesthetist-manned services 35% overtriage and 2% undertriage. Falls, high age and admittance by paramedics were significantly associated with undertriage. A Triage-Revised Trauma Score (RTS) < 12 in the emergency department reduced the risk for undertriage compared to RTS = 12 (normal value). Field RTS was documented by anaesthetists in 64% of the patients compared to 33% among paramedics.Patients subject to undertriage had an ISS-adjusted Odds Ratio for 30-day mortality of 2.34 (95% CI 1.6-3.4, p < 0.001) compared to those correctly triaged to TTA.

CONCLUSION

Triage precision had not improved after TTA guideline introduction. Anaesthetists perform precise trauma triage, whereas paramedics have potential for improvement. Skewed mission profiles makes comparison of differences in triage precision difficult, but criteria or the use of them may contribute. Massive undertriage among paramedics is of grave concern as patients exposed to undertriage had increased risk of dying.

Prehospital trauma system in a low-income country: system maturation and adaptation during 8 years

BACKGROUND

Of all deaths from injury, 90% occur in low- and middle-income countries, and most of the injured die before reaching a hospital. We have previously shown that a rural trauma system in Northern Iraq significantly reduced mortality in victims of mines and war injuries. In this follow-up study, we evaluated the adaptation and maturation of the system to changing injury patterns, focusing on mortality, time intervals from injury to medical help, and treatment effect on the physiologic impact of injuries.

METHODS

Approximately 6,000 first responders and 88 paramedics were trained in Northern Iraq from 1996 to 2004 and treated 2,349 victims. All patients were prospectively registered with monitoring of time intervals, interventions performed, prehospital treatment effect, and mortality.

RESULTS

Injury pattern changed markedly during the study period, with penetrating injuries decreasing from 91% to 15%. Mortality in victims of mines and war injuries (n = 919) decreased from 28.7% to 9.4% (p = 0.001), as did the time interval from injury to first medical help, from 2.4 hours to 0.6 hours (p = 0.002). The prehospital treatment effect improved significantly in the later part of the study period compared with the first years (p < 0.0005). Improvement was maintained in new injury groups. Retention of paramedics in the program was 72% after 8 years.

CONCLUSIONS

This low-tech prehospital emergency system designed for dealing with penetrating trauma matured by reducing time to first medical help and by improving physiologic parameters after prehospital treatment during the 8-year study period. The program adapted to changing injury patterns without compromising results.

Trauma team activation and the impact on mortality

BACKGROUND

Trauma centers use injury mechanism, physiology, and anatomic criteria to determine the extent of trauma team activation (TTA). We examined whether physiologic variables in our three-tier TTA system stratified patients appropriately by injury severity and mortality.

METHODS

The trauma registry at our Level I trauma center was retrospectively reviewed for full (level 1 or L1), partial (level 2 or L2), and limited (level 3) adult TTA. Data were collected on age, injury severity score (ISS), hospital length of stay, systolic blood pressure (SBP), heart rate, respiratory rate (RR), Glasgow coma score (GCS), and intubation status. Penetrating injuries, traumatic arrests, and interfacility transfers were excluded. Data are median (25%75%). Statistical analysis included hazard ratios (HzR), Kruskal-Wallis, chi, and survival analyses. The p value overall was <0.05, and pair wise was <0.05 versus L1.

RESULTS

There were 494 adult TTAs for blunt injury from the scene out of 1,969 admissions. Variables associated with mortality (HzR; 95% confidence interval) by univariate analysis include SBP <90 (9.4; 4.2, 21.2), RR >29 or <10 (17.8; 4.8, 66.0), intubation status (4.5; 2.3, 8.9), and GCS <8 (9.7; 4.8, 19.9). When combined in a multivariate model to evaluate multiple predictors simultaneously, SBP <90 and GCS <8 appear to be the strongest predictors of mortality (RR and intubation were not significant in the presence of SBP and GCS). The three-tier system identified patients with increased ISS and early (< or =4 weeks) mortality risk. There was a statistically significant difference in survival between L1 and L2 at 38 days, but not for >38 days (p = 0.739).

CONCLUSIONS

TTA criteria selected patients with greater ISS and early mortality, but impact on long-term survival may not be appreciated. Full TTA criteria for blunt injury may be limited to GCS <8, SBP <90, RR >29 or <10, and intubation status.

A critical appraisal of opportunities for wearable medical sensors

This paper provides an appraisal of the sensor requirements and prospects available for the growing field of wearable medical sensors. The results of a literature survey for various sensor use-models indicate that the design goals for each intended sensor application must focus on task specific criteria for ultimate sensor acceptance. Provided use-models include the examination of the relevant medical problems, the diagnostic utility of the available physiologic signals, and the impact of false alarms on the specific implementation area.

The objective medical emergency team activation criteria: a case-control study

OBJECTIVE

To evaluate the ability of pre-defined clinical criteria to identify patients who subsequently suffer cardiac arrest, unplanned intensive care unit admission or unexpected death; to determine the ability of modified criteria to identify these patients.

DESIGN

Nested, matched case-control study.

SETTING

Seven Australian public hospitals.

PATIENTS AND PARTICIPANTS

Four hundred and fifty cases and 520 controls matched for age, sex, hospital, and hospital ward.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Highest and lowest respiratory and heart rates, lowest systolic blood pressure, presence of threatened airway, seizures or decrease in Glasgow Coma Scale score of greater than two points and incidence of the three adverse events were measured. Combining a heart rate greater than 140, respiratory rate greater than 36, a systolic blood pressure less than 90 mmHg and a greater than two point reduction in the Glasgow Coma Scale identified adverse events with a sensitivity of 49.1% (44.4-53.8%), specificity of 93.7% (91.2-95.6%), and positive predictive value of 9.8% (8.7-11.1%). Adding threatened airway, seizures, low respiratory rate and low heart rate did not substantially improve sensitivity (50.4%; 45.7-55.2%). After modifying the cut-off values for respiratory rate, heart rate and systolic blood pressure, the best achievable positive predictive value remained below 16%.

CONCLUSIONS

In combination, the respiratory rate, heart rate, systolic blood pressure, and level of consciousness identify patients at risk of cardiac arrest, unplanned intensive care admission or unexpected death with high specificity; however the sensitivity and positive predictive value are relatively low, even after modification of the activation criteria cut-off values.

Comparison of respiratory rate and peripheral oxygen saturation to assess severity in trauma patients

OBJECTIVE

Physiological variables are important in the assessment of trauma patients. The role of respiratory rate (RR) and peripheral oxygen saturation (SpO(2)) remains a matter of debate. We therefore assessed the role of RR and SpO(2) in predicting death in trauma patients.

DESIGN

Prospective analysis of a multicentric cohort of trauma patients in 2002.

PATIENTS

A cohort of 1,481 trauma patients cared for by a prehospital mobile intensive care unit (mean age 38 +/- 17 years, 91% blunt and 9% penetrating trauma).

INTERVENTION

None.

RESULTS

Systolic arterial blood pressure, heart rate, Glasgow coma scale, RR and SpO(2) were recorded and the Injury Severity Score (ISS) and Trauma Related Injury Severity Score (TRISS) calculated. TRISSn was obtained by neutralizing RR. Systolic arterial blood pressure (99.9%), heart rate (99.9%), and Glasgow coma scale (99.3%) were recorded in most patients, but not RR (63%) and SpO(2) (67%). In patients with both RR and SpO(2) recording (n=675), the discrimination and calibration of TRISS was not significantly modified when RR was neutralized. Whatever the manner of expressing RR and SpO(2) (continuous, five classes, dichotomous), none was significant in predicting mortality with TRISSn. Initial SpO(2) was abnormal (< 90%) and recorded again at the hospital in 97 patients, and the proportion of patients with a non-measurable SpO(2) significantly decreased (8 vs. 42%, p < 0.001) and measurable SpO(2) markedly increased (median 99 vs. 85%, p < 0.001).

CONCLUSION

Respiratory rate and SpO(2) do not add significant value to other variables when predicting mortality in severe trauma patients.

Physiologic trauma triage criteria in adult trauma patients: are they effective in saving lives by transporting patients to trauma centers?

BACKGROUND

Trauma triage criteria have been in place for many years and were updated in 1999 by the American College of Surgeons. We are unaware of any studies that have directly examined the ability of these criteria to reduce short-term mortality by transporting patients to trauma centers rather than to noncenters.

STUDY DESIGN

Retrospective observational cohort study of adult patients meeting physiologic triage criteria who were transported to 9 regional (Level I) trauma centers, 21 area (Level II) trauma centers, and 119 noncenters in New York in 1996 to 1998. For each triage criterion and for one or more of the criteria, odds ratios and their confidence intervals for mortality in regional and area trauma centers versus noncenters and odds ratios and their confidence intervals for mortality in regional centers versus area centers and noncenters were used to measure performance.

RESULTS

Patients in regional trauma centers had considerably lower mortality than patients in area trauma centers and noncenters for two individual triage criteria and for patients with one or more triage criteria (odds ratio, 0.75; 95% CI, 0.63-0.90 for one or more criteria). Also, patients with head injuries who were treated in regional centers had notably lower mortality than patients in other hospitals (odds ratio, 0.67; 95% CI, 0.53-0.85).

CONCLUSIONS

In New York, regional trauma centers exhibit considerably lower mortality than area trauma centers or noncenters for adult patients meeting specific physiologic triage criteria. It is important that population-based trauma systems with data from centers and noncenters be developed for the purpose of evaluating and redesigning trauma systems.