Mechanism of injury and special considerations as predictive of serious injury: A systematic review.

Objectives: The Centers for Disease Control and Prevention\u27s field triage guidelines (FTG) are routinely used by emergency medical services personnel for triaging injured patients. The most recent (2011) FTG contains physiologic, anatomic, mechanism, and special consideration steps. Our objective was to systematically review the criteria in the mechanism and special consideration steps that might be predictive of serious injury or need for a trauma center. Methods: We conducted a systematic review of the predictive utility of mechanism and special consideration criteria for predicting serious injury. A research librarian searched in Ovid Medline, EMBASE, and the Cochrane databases for studies published between January 2011 and February 2021. Eligible studies were identified using a priori inclusion and exclusion criteria. Studies were excluded if they lacked an outcome for serious injury, such as measures of resource use, injury severity scores, mortality, or composite measures using a combination of outcomes. Given the heterogeneity in populations, measures, and outcomes, results were synthesized qualitatively focusing on positive likelihood ratios (LR+) whenever these could be calculated from presented data or adjusted odds ratios (aOR

Mechanical Ventilation Strategies in Massive Chest Trauma

In the realm of trauma and critical care, intensivists are challenged in the management of patients demonstrating respiratory and hemodynamic instability after sustaining massive chest trauma. A fundamental goal of critical care management is to avoid hypoxia and hypoventilation, the two main causes of mortality in the acute period following trauma. For most chest trauma patients, endotracheal intubation and chest tube insertion are the mainstays of treatment; however, a subset of these life-threatening injuries will require a more specialized approach. A good trauma history and physical examination are essential. Elucidating the mechanism of injury, combined with assessment of the respiratory and hemodynamic status of the patient, can lead to prompt and appropriate intervention. Hemodynamic instability or a high output of bloody chest tube drainage may require other surgical intervention, such as a thoracotomy for pericardial tamponade or uncontrolled hemorrhage. In some cases, a laparotomy is required (eg, diaphragmatic rupture) In a recent multicenter review, Karmy-Jones and colleagues [2] noted a 40% incidence of emergent thoracotomy for penetrating injury, versus 17% incidence of emergent thoracotomy for blunt chest injury. Their reported 31% incidence of patients requiring pulmonary parenchymal procedure at thoracotomy was higher than the 20% rate generally reported in the literatur

Helicopters and injured kids

BackgroundHelicopter emergency medical services (HEMS) are frequently used to transport injured children, despite unclear evidence of benefit. The study objective was to evaluate the association of HEMS compared with ground emergency medical services (GEMS) transport with outcomes in a national sample of pediatric trauma patients.MethodsPatients 15 years or younger undergoing scene transport by HEMS or GEMS in the National Trauma Data Bank from 2007 to 2012 were included. Propensity score matching was used to match HEMS and GEMS patients for likelihood of HEMS transport based on demographics, prehospital physiology and time, injury severity, and geographic region. Absolute standardized differences of less than 0.1 indicated adequate covariate balance between groups after matching. The primary outcome was in-hospital survival, while the secondary outcome was discharge disposition in survivors. Conditional logistic regression determined the association between HEMS versus GEMS transport with outcomes while controlling for demographics, admission physiology, injury severity, nonaccidental trauma, and in-hospital complications not accounted for in the propensity score. Subgroup analysis was performed in patients with a transport time of greater than 15 minutes to capture patients with the potential for HEMS transport.ResultsA total of 25,700 HEMS/GEMS pairs were matched from 166,594 patients. Groups were well matched, with all propensity score variables having absolute standardized differences of less than 0.1. In matched patients, HEMS was associated with a 72% increase in odds of survival compared with GEMS (adjusted odds ratio, 1.72; 95% confidence interval, 1.26-2.36; p < 0.01). Transport mode was not associated with discharge disposition (p = 0.47). Subgroup analysis included 17,657 HEMS/GEMS pairs. HEMS was again associated with a significant increase in odds of survival (adjusted odds ratio, 1.81; 95% confidence interval, 1.24-2.65; p < 0.01), while transport mode was not associated with discharge disposition (p = 0.58).ConclusionScene transport by HEMS was associated with improved odds of survival compared with GEMS in pediatric trauma patients. Further study is warranted to understand the underlying mechanisms and develop specific triage criteria for HEMS transport in this population.Level of evidenceTherapeutic study, level III

Geographic Variation in Outcome Benefits of Helicopter Transport for Trauma in the United States

ObjectiveEvaluate the effect of US geographic region on outcomes of helicopter transport (HT) for trauma.BackgroundHT is an integral component of trauma systems. Evidence suggests that HT is associated with improved outcomes; however, no studies examine the impact of geographic variation on outcomes for HT.MethodsRetrospective cohort study of patients undergoing scene HT or ground transport in the National Trauma Databank (2009-2012). Subjects were divided by US census region. HT and ground transport subjects were propensity-score matched based on prehospital physiology and injury severity. Conditional logistic regression was used to evaluate the effect of HT on survival and discharge to home in each region. Region-level characteristics were assessed as potential explanatory factors.ResultsA total of 193,629 pairs were matched. HT was associated with increased odds of survival and discharge to home; however, the magnitude of these effects varied significantly across regions (P < 0.01). The South had the greatest survival benefit (odds ratio: 1.44; 95% confidence interval: 1.39-1.49, P < 0.01) and the Northeast had the greatest discharge to home benefit (odds ratio: 1.29; 95% confidence interval: 1.18-1.41, P < 0.01). A subset of region-level characteristics influenced the effect of HT on each outcome, including helicopter utilization, injury severity, trauma center and helicopter distribution, trauma center access, traffic congestion, and urbanicity (P < 0.05).ConclusionsGeographic region impacts the benefits of HT in trauma. Variations in resource allocation partially account for outcome differences. Policy makers should consider regional factors to better assess and allocate resources within trauma systems to optimize the role of HT

Not all prehospital time is equal

BackgroundTrauma is time sensitive, and minimizing prehospital (PH) time is appealing. However, most studies have not linked increasing PH time with worse outcomes because raw PH times are highly variable. It is unclear whether specific PH time patterns affect outcomes. Our objective was to evaluate the association of PH time interval distribution with mortality.MethodsPatients transported by emergency medical services in the Pennsylvania trauma registry from 2000 to 2013 with a total PH time (TPT) of 20 minutes or longer were included. TPT was divided into three PH time intervals: response, scene, and transport time. The number of minutes in each PH time interval was divided by TPT to determine the relative proportion each interval contributed to TPT. A prolonged interval was defined as any one PH interval contributing equal to or greater than 50% of TPT. Patients were classified by prolonged PH interval or no prolonged PH interval (all intervals < 50% of TPT). Patients were matched for TPT, and conditional logistic regression determined the association of mortality with PH time pattern, controlling for confounders. PH interventions were explored as potential mediators, and PH triage criteria used identify patients with time-sensitive injuries.ResultsThere were 164,471 patients included. Patients with prolonged scene time had increased odds of mortality (odds ratio, 1.21; 95% confidence interval, 1.02-1.44; p = 0.03). Prolonged response, transport, and no prolonged interval were not associated with mortality. When adjusting for mediators including extrication and PH intubation, prolonged scene time was no longer associated with mortality (odds ratio, 1.06; 95% confidence interval, 0.90-1.25; p = 0.50). Together, these factors mediated 61% of the effect between prolonged scene time and mortality. Mortality remained associated with prolonged scene time in patients with hypotension, penetrating injury, and flail chest.ConclusionProlonged scene time is associated with increased mortality. PH interventions partially mediate this association. Further study should evaluate whether these interventions drive increased mortality because they prolong scene time or by another mechanism, as reducing scene time may be a target for intervention.Level of evidencePrognostic/epidemiologic study, level III

Development and Validation of the Air Medical Prehospital Triage Score for Helicopter Transport of Trauma Patients

ObjectiveThe aim of this study was to develop and internally validate a triage score that can identify trauma patients at the scene who would potentially benefit from helicopter emergency medical services (HEMS).Summary background dataAlthough survival benefits have been shown at the population level, identification of patients most likely to benefit from HEMS transport is imperative to justify the risks and cost of this intervention.MethodsRetrospective cohort study of subjects undergoing scene HEMS or ground emergency medical services (GEMS) in the National Trauma Databank (2007-2012). Data were split into training and validation sets. Subjects were grouped by triage criteria in the training set and regression used to determine which criteria had a survival benefit associated with HEMS. Points were assigned to these criteria to develop the Air Medical Prehospital Triage (AMPT) score. The score was applied in the validation set to determine whether subjects triaged to HEMS had a survival benefit when actually transported by helicopter.ResultsThere were 2,086,137 subjects included. Criteria identified for inclusion in the AMPT score included GCS <14, respiratory rate <10 or >29, flail chest, hemo/pneumothorax, paralysis, and multisystem trauma. The optimal cutoff for triage to HEMS was ≥2 points. In subjects triaged to HEMS, actual transport by HEMS was associated with an increased odds of survival (AOR 1.28; 95% confidence interval [CI] 1.21-1.36, P < 0.01). In subjects triaged to GEMS, actual transport mode was not associated with survival (AOR 1.04; 95% CI 0.97-1.11, P = 0.20).ConclusionsThe AMPT score identifies patients with improved survival following HEMS transport and should be considered in air medical triage protocols

Helicopter transport improves survival following injury in the absence of a time-saving advantage

BackgroundAlthough survival benefits have been shown at the population level, it remains unclear what drives the outcome benefits for helicopter emergency medical services (HEMS) in trauma. Although speed is often cited as the vital factor of HEMS, we hypothesized a survival benefit would exist in the absence of a time savings over ground emergency medical services (GEMS). The objective was to examine the association of survival with HEMS compared with GEMS transport across similar prehospital transport times.MethodsWe used a retrospective cohort of scene HEMS and GEMS transports in the National Trauma Databank (2007-2012). Propensity score matching was used to match HEMS and GEMS subjects on the likelihood of HEMS transport. Subjects were stratified by prehospital transport times in 5-minute increments. Conditional logistic regression determined the association of HEMS with survival across prehospital transport times strata controlling for confounders. Transport distance was estimated from prehospital transport times and average HEMS/GEMS transport speeds.ResultsThere were 155,691 HEMS/GEMS pairs matched. HEMS had a survival benefit over GEMS for prehospital transport times between 6 and 30 minutes. This benefit ranged from a 46% increase in odds of survival between 26 and 30 minutes (adjusted odds ratio [AOR], 1.46; 95% CI, 1.11-1.93; P < .01) to an 80% increase in odds of survival between 16 and 20 minutes (AOR, 1.80; 95% CI, 1.51-2.14; P < .01). This prehospital transport times window corresponds to estimated transport distance between 14.3 and 71.3 miles for HEMS and 3.3 and 16.6 miles for GEMS.ConclusionWhen stratified by prehospital transport times, HEMS had a survival benefit concentrated in a window between 6 and 30 minutes. Because there was no time-savings advantage for HEMS, these findings may reflect care delivered by HEMS providers