Helicopter retrieval of primary trauma patients by a paramedic helicopter service

Emergency Air Transport of Patients with Acute Chest Pain in the Adriatic Islands of Croatia: A Four-Year Analysis

BACKGROUND

An efficient first-aid system usually supports ground services with a helicopter emergency medical service (HEMS). An HEMS is important for patients with acute chest pain on remote islands. The current study sought to identify the characteristics of HEMS in acute chest pain cases on the Croatian Adriatic islands over a four-year period.

METHODS

We conducted a four-year observational study to investigate HEMS from Adriatic islands. The study population consisted of all patients with acute coronary syndrome or pulmonary embolisms who were urgently transferred by HEMS to the University Hospital in Split 1 June 2018-1 June 2022.

RESULTS

During the observation period, 222 adult patients (67 females, or 30.2%) were urgently transferred. The mean age was 71.81 ± 13.42 years. The most common diagnosis was ST-elevated myocardial infarction (113, 50.9%). Most of the HEMS cases were from Hvar (91, 41.0%). The mean call-to-flight time was 19.10 ± 10.94 min, and the total time from call to hospital was 68.50 ± 22.29 min. The total time from call to hospital was significantly correlated with call-to-flight time (r = 0.761, P < 0.001). Of the 222 participants, 5 (2.25%) were transported for more than 120 min, and 35 (15.8%) were transported for more than 90 min.

CONCLUSION

This study provided a detailed insight into HEMS in the area of the Croatian Adriatic islands. The average time from the call to the helicopter taking off was 19.10 min. An increase in dispatching time has a significant impact on the prolongation of the total time for the hospital admission. Shortening the response time is critical to reducing hospital arrival time.

Effect of Helicopter Transportation of Acute Ischemic Stroke Patients on Mortality and Functional Outcomes: A Systematic Review and Meta-Analysis

OBJECTIVE

The "time is brain" concept denotes the importance of the expedited transfer of patients to stroke care centers. Helicopter emergency medical services (HEMS) can reduce the time to definitive care, which could improve neurologic prognosis and reduce mortality.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, a search for randomized controlled trials, nonrandomized controlled trials, and prospective and retrospective cohort studies was performed through specific databases from inception to February 2020. Helicopter, acute stroke, and their synonyms (according to Medical Subject Headings) were included in this search. The Newcastle-Ottawa Scale was used to assess the quality of the included studies, and the Egger test was used to assess for publication bias.

RESULTS

A total of 8 studies matched the inclusion criteria and were included for meta-analysis. The overall number recruited for helicopter transportation was 1,372, and for emergency standard transportation, it was 8,587. The association among HEMS and mortality was not statistically significant (odds ratio [OR] = 0.7; 95% confidence interval [CI], 0.60-1.06; P = .12). There was a significant association between good outcomes and HEMS (OR = 2; 95% CI, 1.79-2.34; P ≤ .001), and the overall poor neurologic outcome was reduced (OR = 0.52; 95% CI, 0.46-0.60; P ≤ .001).

CONCLUSION

A good neurologic outcome was higher with HEMS compared with emergency standard transportation. The mortality rate was less in the emergency standard transportation group after pooled analysis but was not significant; the reduction in a poor outcome was statistically significant.

Competitive advantage gained from the use of helicopter emergency medical services (HEMS) for trauma patients: Evaluation of 1724 patients

OBJECTIVES

The aim of the study was to analyze helicopter emergency medical service (HEMS) in comparison to EMS, in respect to patient's mortality and morbidity.

DESIGN

From a cohort of traumatized patients (n = 1724) prospectively enrolled in the German trauma registry (DGU-R) at Frankfurt University Hospital from 2009 to 2013, 1646 could be analyzed for in-hospital mortality and short-term outcome (GOS) at discharge and compared between HEMS and EMS.

MEASUREMENTS AND MAIN RESULTS

129 patients (7.8%) died in the hospital. Unadjusted mortality was significantly lower in the HEMS group compared to EMS (p = 0.001). In a multiple logistic regression analysis after adjustment of variables including reanimation and age as the strongest predictors, in-hospital mortality was significantly reduced in HEMS (p = 0.014, OR = 0.21). Further predictors in the multiple logistic regression analysis were GCS > = 8 (p = 0.001), RRsys (p < 0.001), ISS at Head/Neck > = 3 (p = 0.003), and total ISS > = 9 (p < 0.001). Total rescue time and on scene time were associated with mortality (p < 0.001) but not included in the multiple logistic regression model. Without adjustment, short-term outcome (GOS) was significantly improved (p = 0.014). In a linear model, after adjusting for multiple variables including age, ISS Head/Neck > = 3, ISS Extremities > = 3, GCS > = 8, and RRsys as the strongest predictors (p < 0.001), the association remained significant (p = 0.043). Further predictors in the multiple linear regression analysis were total ISS > = 9 (p = 0.002), ISS abdomen (p = 0.001), and ISS Chest (p = 0.011).

CONCLUSIONS

A significant improvement for in-hospital survival for HEMS could be demonstrated. Especially in Germany, with a high number of secondary call outs (about 44%) after EMS has already reached the traumatized patient, HEMS must be the first choice for severely injured trauma patients. Dispatch criteria for immediate alarm of HEMS are recommended under practical considerations.

Can a single primary care paramedic configuration safely transport low-acuity patients in air ambulances?

OBJECTIVE

To determine if utilizing a single paramedic crew configuration is safe for transporting low acuity patients requiring only a primary care paramedic (PCP) level of care in Air Ambulances.

METHODS

We studied single-PCP transports of low acuity patients done by contract air ambulance carriers, organized by Ornge (Ontario's Air Ambulance Service) for one year. We only included interfacility transports. We excluded all scene calls, and all Code 4 (emergent) calls. Our primary outcome was clinical deterioration during transport. We then asked a panel to analyze each case of deterioration to determine if a dual-PCP configuration might have reasonably prevented the deterioration or have better treated the deterioration, compared to a single-PCP configuration.

RESULTS

In one year, contract carriers moved 3264 patients, who met inclusion criteria. 85% were from Northern Ontario. There were 21 cases of medical deterioration (0.6%±0.26%). Paper charts were found for 20 of these cases. Most were self-limited cases of pain or nausea. A small number of cases (n=5) were cardiorespiratory decompensation. There was 100% consensus amongst the panel that all cases of clinical deterioration were not related to team size. There was also 100% consensus that a dual-PCP team would not have been better able to deal with the deterioration, compared to a single-PCP crew.

CONCLUSIONS

We found that using a single-PCP configuration for transporting low acuity patients is safe. This finding is particularly important for rural areas where air ambulance is the only means for accessibility to care and where staffing issues are magnified.

Helicopter emergency medical services for adults with major trauma

BACKGROUND

Although helicopters are presently an integral part of trauma systems in most developed nations, previous reviews and studies to date have raised questions about which groups of traumatically injured people derive the greatest benefit.

OBJECTIVES

To determine if helicopter emergency medical services (HEMS) transport, compared with ground emergency medical services (GEMS) transport, is associated with improved morbidity and mortality for adults with major trauma.

SEARCH METHODS

We ran the most recent search on 29 April 2015. We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library (Cochrane Central Register of Controlled Trials; CENTRAL), MEDLINE (OvidSP), EMBASE Classic + EMBASE (OvidSP), CINAHL Plus (EBSCOhost), four other sources, and clinical trials registers. We screened reference lists.

SELECTION CRITERIA

Eligible trials included randomized controlled trials (RCTs) and nonrandomized intervention studies. We also evaluated nonrandomized studies (NRS), including controlled trials and cohort studies. Each study was required to have a GEMS comparison group. An Injury Severity Score (ISS) of at least 15 or an equivalent marker for injury severity was required. We included adults age 16 years or older.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and assessed the risk of bias of included studies. We applied the Downs and Black quality assessment tool for NRS. We analyzed the results in a narrative review, and with studies grouped by methodology and injury type. We constructed 'Summary of findings' tables in accordance with the GRADE Working Group criteria.

MAIN RESULTS

This review includes 38 studies, of which 34 studies examined survival following transportation by HEMS compared with GEMS for adults with major trauma. Four studies were of inter-facility transfer to a higher level trauma center by HEMS compared with GEMS. All studies were NRS; we found no RCTs. The primary outcome was survival at hospital discharge. We calculated unadjusted mortality using data from 282,258 people from 28 of the 38 studies included in the primary analysis. Overall, there was considerable heterogeneity and we could not determine an accurate estimate of overall effect.Based on the unadjusted mortality data from six trials that focused on traumatic brain injury, there was no decreased risk of death with HEMS. Twenty-one studies used multivariate regression to adjust for confounding. Results varied, some studies found a benefit of HEMS while others did not. Trauma-Related Injury Severity Score (TRISS)-based analysis methods were used in 14 studies; studies showed survival benefits in both the HEMS and GEMS groups as compared with MTOS. We found no studies evaluating the secondary outcome, morbidity, as assessed by quality-adjusted life years (QALYs) and disability-adjusted life years (DALYs). Four studies suggested a small to moderate benefit when HEMS was used to transfer people to higher level trauma centers. Road traffic and helicopter crashes are adverse effects which can occur with either method of transport. Data regarding safety were not available in any of the included studies. Overall, the quality of the included studies was very low as assessed by the GRADE Working Group criteria.

AUTHORS' CONCLUSIONS

Due to the methodological weakness of the available literature, and the considerable heterogeneity of effects and study methodologies, we could not determine an accurate composite estimate of the benefit of HEMS. Although some of the 19 multivariate regression studies indicated improved survival associated with HEMS, others did not. This was also the case for the TRISS-based studies. All were subject to a low quality of evidence as assessed by the GRADE Working Group criteria due to their nonrandomized design. The question of which elements of HEMS may be beneficial has not been fully answered. The results from this review provide motivation for future work in this area. This includes an ongoing need for diligent reporting of research methods, which is imperative for transparency and to maximize the potential utility of results. Large, multicenter studies are warranted as these will help produce more robust estimates of treatment effects. Future work in this area should also examine the costs and safety of HEMS, since multiple contextual determinants must be considered when evaluating the effects of HEMS for adults with major trauma.

Effective transport for trauma patients under current circumstances in Korea: a single institution analysis of treatment outcomes for trauma patients transported via the domestic 119 service

In Korea, which still lacks a well-established trauma care system, the inability to transport patients to adequate treatment sites in a timely manner is a cause of low trauma patient survival. As such, this study was conducted to serve as a basis for the establishment of a future trauma transport system. We performed a comparative analysis of the transport time, and treatment outcomes between trauma victims transported by ground ambulance (GAMB) and those transported via the helicopter emergency medical service (HEMS) through the National Emergency Management Agency's 119 reporting system, which is similar to the 911 system of the United States, from March 2011 to May 2014. The HEMS-transported patients received treatment instructions, by remote communication, from our trauma specialists from the time of accident reporting; in certain instances, members of the trauma medical staff provided treatment at the scene. A total of 1,626 patients were included in the study; the GAMB and HEMS groups had 1,547 and 79 patients, respectively. The median transport time was different between 2 groups (HEMS, 60 min vs. GAMB, 47 min, P<0.001) but for all patients was 49 min (less than the golden hour). Outcomes were significantly better in the HEMS compared to the GAMB, using the trauma and injury severity score (survival rate, 94.9% vs. 90.5%; Z score, 2.83 vs. -1.96; W score, 6.7 vs. -0.8). A unified 119 service transport system, which includes helicopter transport, and the adoption of a trauma care system that allows active initial involvement of trauma medical personnel, could improve the treatment outcome of trauma patients.

Ten years of helicopter emergency medical services in Germany: do we still need the helicopter rescue in multiple traumatised patients?

BACKGROUND

Helicopter emergency medical service (HEMS) has been established in the preclinical treatment of multiple traumatised patients despite an ongoing controversy towards the potential benefit. Celebrating the 20th anniversary of TraumaRegister DGU(®) of the German Trauma Society (DGU) the presented study intended to provide an overview of HEMS rescue in Germany over the last 10 years analysing the potential beneficial impact of a nationwide helicopter rescue in multiple traumatised patients.

PATIENTS AND METHODS

We analysed TraumaRegister DGU(®) including multiple traumatised patients (ISS ≥ 16) between 2002 and 2012. In-hospital mortality was defined as main outcome. An adjusted, multivariate regression with 13 confounders was performed to evaluate the potential survival benefit.

RESULTS

42,788 patients were included in the present study. 14,275 (33.4%) patients were rescued by HEMS and 28,513 (66.6%) by GEMS. Overall, 66.8% (n=28,569) patients were transported to a level I trauma centre and 28.2% (n=12,052) to a level II trauma centre. Patients rescued by HEMS sustained a higher injury severity compared to GEMS (ISS HEMS: 29.5 ± 12.6 vs.

ISS GEMS

27.5 ± 11.8). Helicopter rescue teams performed more on-scene interventions, and mission times were increased in HEMS rescue (HEMS: 77.2 ± 28.7 min. vs. GEMS: 60.9 ± 26.9 min.). Linear regression analysis revealed that the frequency of HEMS rescue has decreased significantly between 2002 and 2012. In case of transportation to level I trauma centres a decrease of 1.7% per year was noted (p<0.001) while a decline of 1.6% per year (p<0.001) was measured for level II trauma centre admissions. According to multivariate logistic regression HEMS was proven a positive independent survival predictor between 2002 and 2012 (OR 0.863; 95%-CI 0.800-0.930; Nagelkerkes-R(2) 0.539) with only little differences between each year.

CONCLUSIONS

This study was able to prove an independent survival benefit of HEMS in multiple traumatised patients during the last 10 years. Despite this fact, a constant decline of HEMS rescue missions was found in multiple trauma patients due to unknown reasons. We concluded that HEMS should be used more often in case of trauma in order to guarantee the proven benefit for multiple traumatised patients.

When birds can't fly: an analysis of interfacility ground transport using advanced life support when helicopter emergency medical service is unavailable

BACKGROUND

Helicopter emergency medical service (HEMS) transport of trauma patients is costly and of unproven benefit. Recent retrospective studies fail to control for crew expertise and therefore compare highly trained advance life support with less-trained basic life support crews. The purpose of our study was to compare HEMS with ground, interfacility transport while controlling for crew training. We hypothesized that patients transported by HEMS would experience shorter interhospital transport time and reduced mortality.

METHODS

Our National Trauma Registry of the American College of Surgeons database was retrospectively queried to identify consecutive interfacility, hospital transfers (January 1, 2008, to November 1, 2012) to our Level I trauma center. Transfers were stratified by transportation vehicle (i.e., HEMS vs. ground transport). Cohorts were compared across standard demographic and clinical variables using univariate analysis. Multivariate logistic regression was performed to determine the association of these variables with mortality.

RESULTS

The HEMS (n = 2,190) and ground (n = 223) cohorts were well matched overall, with no significant differences for demographics, injury severity, physiology, hospital length of stay, or complications. Median (interquartile range) time to definitive care was significantly lower for HEMS (150 [114] minutes vs. 255 [157] minutes, p < 0.001), without change in mortality (9.0% vs. 8.1%, p = 0.71). Multivariate logistic regression did not identify an association between transport mode and mortality.

CONCLUSION

Despite faster interfacility transport times, HEMS offered no mortality benefit compared with ground when crew expertise was controlled for, contradicting recent large, retrospective National Trauma Data Bank studies. Our study may represent the best approximation of a prospective study by focusing on patients deemed worthy of HEMS by referring providers. Although HEMS may seem intuitively beneficial for time-dependent injuries, larger studies with a similar methodology are warranted to justify the cost and risk of HEMS and identify subsets of patients who may benefit.

LEVEL OF EVIDENCE

Prognostic/epidemiologic study, level III.

Clinical manifestations of tension pneumothorax: protocol for a systematic review and meta-analysis

BACKGROUND

Although health care providers utilize classically described signs and symptoms to diagnose tension pneumothorax, available literature sources differ in their descriptions of its clinical manifestations. Moreover, while the clinical manifestations of tension pneumothorax have been suggested to differ among subjects of varying respiratory status, it remains unknown if these differences are supported by clinical evidence. Thus, the primary objective of this study is to systematically describe and contrast the clinical manifestations of tension pneumothorax among patients receiving positive pressure ventilation versus those who are breathing unassisted.

METHODS/DESIGN

We will search electronic bibliographic databases (MEDLINE, PubMed, EMBASE, and the Cochrane Database of Systematic Reviews) and clinical trial registries from their first available date as well as personal files, identified review articles, and included article bibliographies. Two investigators will independently screen identified article titles and abstracts and select observational (cohort, case-control, and cross-sectional) studies and case reports and series that report original data on clinical manifestations of tension pneumothorax. These investigators will also independently assess risk of bias and extract data. Identified data on the clinical manifestations of tension pneumothorax will be stratified according to whether adult or pediatric study patients were receiving positive pressure ventilation or were breathing unassisted, as well as whether the two investigators independently agreed that the clinical condition of the study patient(s) aligned with a previously published tension pneumothorax working definition. These data will then be summarized using a formal narrative synthesis alongside a meta-analysis of observational studies and then case reports and series where possible. Pooled or combined estimates of the occurrence rate of clinical manifestations will be calculated using random effects models (for observational studies) and generalized estimating equations adjusted for reported potential confounding factors (for case reports and series).

DISCUSSION

This study will compile the world literature on tension pneumothorax and provide the first systematic description of the clinical manifestations of the disorder according to presenting patient respiratory status. It will also demonstrate a series of methods that may be used to address difficulties likely to be encountered during the conduct of a meta-analysis of data contained in published case reports and series. PROSPERO registration number: CRD42013005826.

Role of Air-Medical Evacuation in Mass-Casualty Incidents—A Train Collision Experience

Background:

On 21 June 2005, a passenger train collided with a truck near Revadim, Israel.The collision resulted in a multiple-scene mass-casualty incident in an area characterized by difficult access and a relatively long distance from trauma centers. A major disaster response was initiated by civilian and military medical forces including the Israeli Air Force (IAF) Search and Rescue teams. The air-medical evacuation from the accident site to the trauma centers, the activities of the airborne medical teams, and the lessons learned from this event are described in this report.

Methods:

A retrospective analysis of data gathered from relevant elements that participated in management, treatment, and evacuation from the accident site was conducted.

Results:

The accident resulted in 289 injured passengers and seven of the injured were killed. Six helicopters (performing nine sorties) participated. Helicopters evacuated trauma victims and aided in transporting air-medical teams to the site of the collision.Overall, 35 trauma victims (10 urgent) were evacuated by air to trauma centers. The length of time between the first helicopter landing and completion of the air evacuation was 83 minutes. The airmedical evacuation operation was controlled by the commander of the IAF Search and Rescue. Different crew compositions were set in real time.

Conclusions:

Air-medical evacuation during this unique event enabled prompt transportation of casualties from the scene to trauma centers and provided reasonable distribution of patients between various centers in the region.This operation highlighted the necessity for flexibility in medical decision-making and the need for non-conventional solutions regarding crew compositions during management of an airborne evacuation in similar settings. Air-medical evacuation should be considered as a part of responses to mass-casualty incidents, especially when the site is remote or characterized by accessibility difficulties.

Do mannequin chests provide an accurate representation of a human chest for simulated decompression of tension pneumothoraxes?

BACKGROUND

Tension pneumothorax (TPX) is an uncommon but life-threatening condition. It is important that this uncommon presentation, managed by needle decompression, is practised by paramedics using a range of educationally sound and realistic mannequins. The objective of this study is to identify if the chest wall thickness (CWT) of training mannequins used for chest decompression is an anatomically accurate representation of a human chest.

METHODS

This is a two-part study. A review of the literature was conducted to identify chest wall thickness in humans and measurement of chest wall thickness on two commonly used mannequins. The literature search was conducted using the Cochrane Central Register of Controlled Trials, MEDLINE, CINAHL, and EMBASE databases from their beginning until the end of May 2012. Key words included chest wall thickness, tension pneumothorax, pneumothorax, thoracostomy, needle thoracostomy, decompression, and needle test. Studies were included if they reported chest wall thickness.

RESULTS

For the literature review, 4 461 articles were located with 9 meeting the inclusion criteria. Chest wall thickness in adults varied between 1.3 cm and 9.3 cm at the area of the second intercostal space mid clavicular line. The Laerdal(®) manikin in the area of the second intercostal space mid clavicular line, right side of the chest was 1.1 cm thick with the left 1.5 cm. The MPL manikin in the same area or on the right side of the chest was 1.4 cm thick but on the left 1.0 cm.

CONCLUSION

Mannequin chests are not an accurate representation of the human chest when used for decompressing a tension pneumothorax and therefore may not provide a realistic experience.

Incidence and outcome of tube thoracostomy positioning in trauma patients

OBJECTIVES

To evaluate the frequency of use, placement site, success and misplacement rates, and need for intervention for tube thoracostomies (TTs), and the complications with endotracheal intubation associated with TT in the prehospital setting.

METHODS

We performed a five-year, retrospective study using the records of 1,065 patients who were admitted to the trauma emergency room at a university hospital and who had received chest radiographs or computed tomography (CT) scans within 30 minutes after admission.

RESULTS

Seven percent of all patients received a TT (5% unilateral, 2% bilateral). Ninety-seven percent of all patients with a TT were endotracheally intubated. The success rate for correctly placed chest tubes was 78%. Twenty-two percent of the chest tubes were misplaced (i.e., too far in the chest, twisted, or bent); half of those had to be corrected, with one needing to be replaced. There were no statistical differences in the frequency of Monaldi or Bülau positions, or the frequency of left or right chest TT. In addition, the two positions did not differ in misplacement rates or the need for intervention. Helicopter emergency medical services physicians used the Monaldi position significantly more frequently than the Bülau position. In-hospital physicians performing interhospital transfer used the Bülau position significantly more frequently, whereas ground emergency medical physicians had a more balanced relationship between the two positions. Tube thoracostomy had no influence on endotracheal tube misplacement rates, and vice versa.

CONCLUSION

Tube thoracostomy positioning mostly depends on the discretion of the physician on scene. The Monaldi and Bülau positions do not differ in misplacement or complication rates.

Lives saved by helicopter emergency medical services: an overview of literature

INTRODUCTION

The objective of this review is to give an overview of literature on the survival benefits of Helicopter Emergency Medical Services (HEMS). The included studies were assessed by study design and statistical methodology.

METHODS

A literature search was performed in the National Library of Medicine's Medline database, extending from 1985 until April 2007. Manuscripts had to be written in English and describe effects of HEMS on survival expressed in number of lives saved. Moreover, analysis had to be performed using adequate adjustment for differences in case-mix.

RESULTS

Sixteen publications met the inclusion criteria. All indicated that HEMS assistance contributed to increased survival: Between 1.1 and 12.1 additional survivors were recorded for every 100 HEMS uses. A combination of four reliable studies shows overall mortality reduction of 2.7 additional lives saved per 100 HEMS deployments.

CONCLUSION

Literature shows a clear positive effect on survival associated with HEMS assistance. Efforts should be made to promote consistent methodology, including uniform outcome parameters, in order to provide sufficient scientific evidence to conclude the ongoing debate about the beneficial effects of HEMS.

The Safety andEfficacy of Prehospital Needle andTube Thoracostomy by Aeromedical Personnel

BACKGROUND

Aeromedical crews routinely use needle thoracostomy (NT) and tube thoracostomy (TT) to treat major trauma victims (MTVs) with potential tension pneumothorax; however, the efficacy of prehospital NT and TT is unclear.

OBJECTIVES

To explore the efficacy of aeromedical NT and TT in MTVs.

METHODS

A retrospective chart review was performed using prehospital medical records and the county trauma registry over a seven-year period. All MTVs undergoing placement of NT or TT by aeromedical personnel were included; patients with incomplete data were excluded. Descriptive statistics were used to report the incidence of air release, clinical improvement (improved breath sounds or compliance if intubated, decreased dyspnea if nonintubated), and vital signs improvements (systolic blood pressure [SBP] increase to =90 mm Hg or increase by 5 mm Hg if < 90 mm Hg; heart rate improvement to 60-100 beats/min, increase by 10 beats/min if < 60 BPM, or decrease by 10 beats/min if > 100 beats/min; oxygen saturation increase if < 95%) for both NT and TT as documented in prehospital medical records. Survival and improvement in SBP based on trauma registry data were recorded for patients stratified by initial SBP.

RESULTS

A total of 136 procedures (89 NTs and 47 TTs) in 81 patients were identified using prehospital medical records over a four-year period. Response rates to NT (60% overall, 32% vital signs) and TT (75% overall, 60% vital signs) were high. Vital signs improvements were observed more often in patients with a pulse and in nonintubated patients. A total of 168 patients were identified in the trauma registry over the seven-year study period. Normalization of SBP was observed in two-thirds of patients with a field SBP = 90 mm Hg and one-third of patients in whom field SBP could not be obtained. A small but significant proportion of patients undergoing prehospital NT and TT, including some with prehospital hypotension and high injury severity, survived to hospital discharge. The incidence of complications was low.

CONCLUSIONS

Aeromedical crews appear to appropriately select MTVs to undergo field NT or TT. A low incidence of complications and a small but significant group of unexpected survivors support continued use of this procedure by aeromedical personnel.

Helicopter Scene Transport of Trauma Patients with Nonlife-Threatening Injuries: A Meta-Analysis

BACKGROUND

Helicopters have become a major part of the modern trauma care system and are frequently used to transport patients from the scene of their injury to a trauma center. While early studies reported decreased mortality for trauma patients transported by helicopters when compared with those transported by ground ambulances, more recent research has questioned the benefit of helicopter transport of trauma patients. The purpose of this study was to determine the percentage of patients transported by helicopter who have nonlife-threatening injuries.

METHODS

A meta-analysis was performed on peer-review research on helicopter utilization. The inclusion criteria were all studies that evaluated trauma patients transported by helicopter from the scene of their injury to a trauma center with baseline parameters defined by Injury Severity Score (ISS), Trauma Score (TS), Revised Trauma Score (RTS), and the likelihood of survival as determined via Trauma Score-Injury Severity Score (TRISS) methodology.

RESULTS

There were 22 studies comprising 37,350 patients that met the inclusion criteria. According to the ISS, 60.0% [99% confidence interval (CI): 54.5-64.8] of patients had minor injuries, According to the TS, 61.4% (99% CI: 60.8-62.0) of patients had minor injuries. According to TRISS methodology, 69.3% (99% CI: 58.5-80.2) of patients had a greater than 90% chance of survival and thus nonlife-threatening injuries. There were 25.8% (99% CI: -1.0-52.6) of patients discharged within 24 hours after arrival at the trauma center.

CONCLUSIONS

The majority of trauma patients transported from the scene by helicopter have nonlife-threatening injuries. Efforts to more accurately identify those patients who would benefit most from helicopter transport from the accident scene to the trauma center are needed to reduce helicopter overutilization.

Prevalence of Tension Pneumothorax in Fatally Wounded Combat Casualties

BACKGROUND

Tension pneumothorax is a potential cause of death in victims of penetrating chest trauma, but little is known about its actual prevalence.

METHODS

Data that are part of the Vietnam Wound Data and Munitions Effectiveness Team study were analyzed to address this question. Radiographs of 978 casualties were examined for evidence of tension pneumothorax using standard radiologic criteria such as pleural separation, displacement of the mediastinum and diaphragm, trachea deviation, and compression of the contralateral lung.

RESULTS

Some or all of the radiographic changes were found in 198 casualties. Autopsy evidence indicated that 79 of these casualties died solely due to a chest wound. The fatal chest injury involved only the lungs in 55 casualties and caused a tension pneumothorax in 26. Fifteen of the 26 lived long enough to receive first aid from a medic or corpsman.

CONCLUSION

Tension pneumothorax was the cause of death in 3 to 4% of fatally wounded combat casualties. Some may be temporarily helped by battlefield thoracentesis.

The Impact of Aeromedical Response to Patients With Moderate to Severe Traumatic Brain Injury

STUDY OBJECTIVE

Aeromedical crews offer an advanced level of practice and rapid transport to definitive care; however, their efficacy remains unproven. Previous studies have used relatively small sample sizes or have been unable to adequately control for the effect of other potentially influential variables. Here we explore the impact of aeromedical response in patients with moderate to severe traumatic brain injury.

METHODS

This was a retrospective analysis using our county trauma registry. All patients with head Abbreviated Injury Score of 3 or greater were included; interfacility transfers were excluded. The impact of aeromedical response was determined using logistic regression, adjusting for age, sex, mechanism, preadmission Glasgow Coma Scale score, head Abbreviated Injury Score, Injury Severity Score, and the presence of preadmission hypotension. Propensity scores were used to account for variability in selection of patients to undergo air versus ground transport. Patients with moderate and severe traumatic brain injury, as defined by head Abbreviated Injury Score and Glasgow Coma Scale score, were compared. Finally, aeromedical patients undergoing field intubation were compared with ground patients undergoing emergency department (ED) intubation.

RESULTS

A total of 10,314 patients meeting all inclusion and exclusion criteria and with complete data sets were identified and included 3,017 transported by aeromedical crews. Overall mortality was 25% in the air- and ground-transported cohorts, but outcomes were significantly better for the aeromedical patients when adjusted for age, sex, mechanism of injury, hypotension, Glasgow Coma Scale score, head Abbreviated Injury Score, and Injury Severity Score (adjusted odds ratio [OR] 1.90; 95% confidence interval [CI] 1.60 to 2.25; P<.0001). Good outcomes (discharge to home, jail, psychiatric facility, rehabilitation, or leaving against medical advice) were also higher in aeromedical patients (adjusted OR 1.36; 95% CI 1.18 to 1.58; P<.0001). The primary benefit appeared to be in more severely injured patients, as reflected by head Abbreviated Injury Score and Glasgow Coma Scale score. Improved survival was also observed for air-transported patients intubated in the field versus ground-transported patients given emergency intubation in the ED (adjusted OR 1.42; 95% CI 1.13 to 1.78; P<.001).

CONCLUSION

Here we analyze a large database of patients with moderate to severe traumatic brain injury. Aeromedical response appears to result in improved outcomes after adjustment for multiple influential factors in patients with moderate to severe traumatic brain injury. In addition, out-of-hospital intubation among air-transported patients resulted in better outcomes than ED intubation among ground-transported patients. Patients with more severe injuries appeared to derive the greatest benefit from aeromedical transport.

Helicopter primary retrieval: Tasking who should do it?

BACKGROUND

Cairns Base Hospital utilizes a helicopter retrieval system, which until 2001 had been tasked and staffed by emergency physicians. Since 2001, the ambulance service has assumed the role of both tasking and staffing the helicopter with intensive care paramedics. The present study examines whether the change has resulted in different activation patterns and patient outcomes.

METHOD

A retrospective chart review over 4 consecutive years, comparing the two groups, was carried out examining 30 day mortality, length of in-hospital stay, transfer rates, the Revised Trauma Score where appropriate and rates of discharge directly from the ED.

RESULTS

A total of 374 patients were retrieved (211 patients in the emergency physician group from 1 April 1999 to 31 March 2001 and 163 in the ambulance group from 1 April 2001 to 31 March 2003) over the 4 year period. The demographics of the two groups were similar. Fifty-four patients in the ambulance group (33.1%) were discharged from the ED without admission while 31 (14.7%) were discharged from the physician group. This was statistically significant (P = 0.0001). There were no other significant differences between the two groups. The subgroup of patients admitted also did not show any significant difference in outcomes.

CONCLUSION

The similarities in outcomes for admitted patients support the view that both groups have similar tasking criteria for high-acuity patients and suggest that paramedics are as efficacious as physicians in delivering prehospital care in this group of patients. However, for lower-acuity patients, there is a statistically significant higher rate of clinically unnecessary taskings by the ambulance group. Given the recent fatal aeromedical accidents in Queensland (Thursday Island 1998, Rockhampton 1999 and Mackay 2003), it would seem prudent to reduce clinically unnecessary retrievals through clinical coordination with appropriately qualified emergency physicians.

Tension pneumothorax--time for a re-think?

This review examines the present understanding of tension pneumothorax and produces recommendations for improving the diagnostic and treatment decision process.

Appropriate use of helicopters to transport trauma patients from incident scene to hospital in the United Kingdom: an algorithm

A simple algorithm has been produced to assist front line ground ambulance personnel, air ambulance crews, and immediate care doctors attending trauma patients in selecting the most appropriate mode of transport from the incident scene to hospital.

Paramedic versus nurse crews in the helicopter transport of trauma patients

INTRODUCTION

A wide variety of opinions exist about using paramedics on flight teams, most of which have not been substantiated by research findings. This study was conducted to explore the outcomes of patients transported by helicopter crews that consisted of either two nurses or a nurse and a paramedic.

METHODS

Using data from the New York State Trauma Registry and prehospital care reports, a retrospective comparison was made between the outcomes of 1193 air medical patients transported either by crews consisting of two nurses (N/N) or a nurse and a paramedic (N/P). The sample included blunt and penetrating trauma patients with an Injury Severity Score greater than or equal to 9 and who were older than 16 years.

RESULTS

The findings indicate the percentages of patients who lived, died, or were discharged home or to rehabilitation were similar for N/P and N/N groups. Using TRISS methodology and the Z statistic, no statistically significant difference was found in observed versus predicted mortality for both groups (P <.05).

CONCLUSION

No significant difference existed in patient outcomes between N/P and N/N crews.

Helicopter transport and blunt trauma mortality: a multicenter trial

BACKGROUND

Despite many studies addressing potential impact of helicopter transport on trauma mortality, debate as to the efficacy of air transport continues.

METHODS

This retrospective study combined trauma registry data from five urban Level I adult and pediatric centers. Logistic regression assessed effect of helicopter transport on mortality while adjusting for age, sex, transport year, receiving hospital, prehospital level of care (Advanced Life Support vs. Basic Life Support), ISS, and mission type (scene vs. interfacility).

RESULTS

The study database comprised 16,699 patients. Crude mortality for Air (9.4%) was 3.4 times (95% CI, 2.9-4.0, p < 0.001) that of Ground (3.0%) patients. In adjusted analysis, helicopter transport was found to be associated with a significant mortality reduction (odds ratio, 0.76; 95% CI, 0.59-0.98; p = 0.031).

CONCLUSION

The results of this study are consistent with an association between helicopter transport mode and increased survival in blunt trauma patients.

Ambulance times of Ankara emergency aid and rescue services' ambulance system

The aim of this study was to determine various times related to the ambulance activities of Ankara Emergency Aid and Rescue Services (EARS) and if necessary contribute to the improvement of them. A descriptive study was planned to determine various times related to the ambulance activities of Ankara EARS. The data was collected by one of the researchers. The study was conducted between 1 October 1995 and 30 September 1996. The variables of the study were: delay time, response time, time at the scene (scene time), round trip time, transport time and total run time of Ankara EARS ambulance activities. Ankara EARS Emergency Call Registry Forms (5638 forms) were evaluated for the above stated variables. The computer program EPI-INFO 5.0 was used in the study. The median response time of Ankara EARS was found to be 9 minutes. In the research year, the median delay time was 2 minutes. Median arrival to patient contact time of Ankara EARS was 2 minutes. Median time at the scene was 7 minutes. Median round trip time of the system was 44 minutes. The median time to arrive at the scene from the ambulance station was 8 minutes. The median transport time was 10 minutes. The median total run time was 30 minutes. As the median response time was found to be 9 minutes it is concluded that there should be more ambulance vehicles to improve this time of Ankara EARS. Due to financial problems, times were recorded manually by the ambulance crew and dispatchers of Ankara EARS. If digital and electronic recording systems are used, these times might be more precise.

Use of an ambulance-based helicopter retrieval service

BACKGROUND

John Hunter Hospital is the major trauma centre for a region covering more than 25,000 square kilometres. The helicopter primary retrieval service for trauma is paramedic staffed and protocol driven. The aim of the present study was to assess the overtriage rate created by such protocols, and to assess the benefit to patient outcomes that may be attributable to the service.

METHODS

The John Hunter Hospital trauma database was used to identify all cases arriving by helicopter in 1996, as well as their demographic details, injury severity score, details of the accident and outcome. An expert panel reviewed the medical records for the 184 primary retrievals. Using a consensus model, estimates of time delay or saving were calculated and likelihood of benefit, no benefit or harm was assessed.

RESULTS

A total of 3087 trauma patients were assessed at John Hunter Hospital in 1996, of which 8% arrived by helicopter. Of the primary retrievals, 67.6% had an injury severity score of 9 or less, with only 17.9% having a score of 16 or greater. Twelve patients were discharged from Emergency and 36% were discharged within 48 h. The overall mortality was 5.0%. Twenty-five per cent of patients were retrieved within 35 km of John Hunter Hospital with minimal attributable benefit. Overall 1.7% of patients were felt to have been potentially harmed, 17.3% to have benefited and 81.0% to have had no attributable benefit related to the helicopter use.

CONCLUSIONS

Although the majority of retrievals are for minor injuries, the service provides benefit for the region. There is potential for harm, however, where base hospitals are overflown in situations where patients have airway compromise, and where patient transfer is delayed due to helicopter activation. Primary helicopter tasking to trauma cases within 35 km of the major trauma centre is seldom beneficial.

Addition of physicians to paramedic helicopter services decreases blunt trauma mortality

BACKGROUND

The authors hypothesized that the addition of critical care physicians to the flight crew of paramedic helicopter services would decrease mortality in blunt trauma, and that this would be due to the greater procedural capability and clinical judgement of the physician.

METHODS

Retrospective comparison was undertaken of patients flown directly from the accident scene over a 28-month period by the paramedic-staffed Westpac Hunter region helicopter to John Hunter Hospital, and the physician-staffed NRMA CareFlight helicopter to Westmead or Nepean Hospitals. Inclusion criteria were blunt trauma and an Injury Severity Score of > 10. Mortality was compared by trauma score-injury severity score (TRISS) methodology.

RESULTS

There were 140 patients in the paramedic treatment group and 67 in the physician group. There were no significant differences between the groups in age, mechanism of injury, distance transported, response, scene or transport times. Physicians intubated a greater proportion of patients (51 vs 10%; P < 0.001) including all patients with a Glasgow Coma Score of < 9. Physicians gave significantly greater volumes of fluids to hypotensive patients (median: 5035 vs 1475 mL: P < 0.001) and performed thoracic decompressions on a larger proportion of patients (12 vs 1%; P < 0.01). The Z statistic for the physician treatment group was 2.72 (P < 0.01 ) compared with -1.16 (P = 0.25) in the paramedic group. The adjusted W statistic was 13.44 (95% CI: 7.80-19.08) suggesting that there would be between eight and 19 extra survivors per 100 patients treated in the physician group compared with the paramedic group.

CONCLUSIONS

Physicians perform a greater number of procedures at accident scenes without increasing scene time. This results in significantly lower mortality. Critical care physicians should be added to paramedic helicopter services for scene response to blunt trauma.

Needle thoracostomy in the prehospital setting

OBJECTIVES

To determine the effect of needle thoracostomy (NT) in the prehospital setting, its frequency of use, and its complication rate.

METHODS

This was a prospective case series from January 1, 1995, to December 31, 1996. Inclusion criteria were all patients who met trauma center criteria, were transported by paramedics to Los Angeles County/University of Southern California Medical Center (a large, urban, level I trauma center), and had placement of a prehospital NT.

RESULTS

Out of 6,241 major trauma patients transported by paramedics over the study period, 108 (1.7%) underwent 114 NTs. Sixty-four patients (59%) sustained gunshot wounds, 32 (30%) sustained stab wounds, eight (7%) were involved in motor vehicle accidents, and the remainder had other types of blunt trauma. The mean injury severity score (ISS) was 22.3, and the overall mortality rate was 28%. Of the patients who received NTs, five (5%) showed objective improvement in field vital signs and seven (7%) had subjective improvement of their dyspnea. Two NTs were found to have not penetrated into the thorax with the catheter tip in the soft tissue. Two patients (2%) received NTs despite the absence of any chest injuries found upon operative intervention, resulting in two iatrogenic pneumothoraxes. No other complications, including vascular injury or infection, were found in any of the patients.

CONCLUSION

Prehospital NT is a procedure infrequently performed by paramedics, even in a busy urban area. While there is a risk of the procedure's being done without proper indication, NT may improve outcomes in a small subset of chest-injured patients.

Cost-effectiveness analysis of helicopter EMS for trauma patients

STUDY OBJECTIVE

To evaluate the cost-effectiveness of helicopter EMS for trauma patients.

METHODS

We applied a cost-effectiveness analysis from the service provider's perspective to cost and effectiveness estimates. The cost estimates comprise direct operating costs and additional survivors' hospital costs. The effectiveness estimates were calculated with the TRISS methodology from literature sources and data from a cohort of patients transported by helicopter during 1994 and 1995. Sensitivity analysis and discounting were used. Cost per life saved and discounted cost per year of life in 1995 US dollars were the main outcome measures.

RESULTS

The reported literature survival benefit ranges from 1 to 12 additional survivors per 100 patients flown. Transport costs were $2,214 per patient, and each additional survivor's hospitalization averaged $15,883. For the base case (5 additional survivors per 100 patients flown), cost per life was $60,163 and discounted cost per year of life $2,454. Sensitivity analysis revealed that discounted cost per year of life could be as high as $9,677 or as low as $1,400 and that it was most dependent on the surviving benefit. These results are comparable to a reported median discounted cost per year of life of %19,000 for other commonly used lifesaving medical interventions.

CONCLUSION

Assuming that helicopter air medical transport provides a substantial survival benefit for trauma patients, our findings suggest that this service is a cost-effective option for the treatment of trauma patients. The magnitude of the survival benefit is the most important factor determining cost-effectiveness.

Helicopter emergency medical services: their role in integrated trauma care

The role of helicopters in trauma management must be considered in the context of the provision of sophisticated, high-quality trauma care. The present review examines the evolution of systems of trauma care, the value of advanced life support (ALS), and the role of the Helicopter Emergency Medical Service (HEMS) in improving outcomes. Comparison is made of outcomes of patients managed by HEMS and road ambulances, and important aspects of HEMS including staffing and safety are discussed. There is a role for HEMS as part of a modern trauma system, in particular in bringing ALS skills and access to expert medical care to the rural accident scene or hospital at distances of up to 160 km. It is of greatest value when it is integrated into a well-organized ambulance service and emergency system with good triage and close medical supervision.

Prehospital emergency rapid sequence induction of anaesthesia

OBJECTIVE

To determine the number of and reasons for rapid sequence inductions done by accident and emergency (A&E) doctors out of hospital as part of the activities of the MEDIC 1 Flying Squad. "Rapid sequence induction" was defined as any attempted endotracheal intubation accompanied by use of drugs to assist intubation and ventilation, including opiates, benzodiazepines, intravenous and topical anaesthetics, and neuromuscular blocking drugs.

METHODS

Retrospective study of all MEDIC 1 and A&E records over the period 1 February 1993 to 28 February 1996 (37 months). The anaesthetic technique used, drugs used, complications, difficulties, reasons for induction out of hospital, and grade of doctor performing the technique were determined.

RESULTS

Various anaesthetic techniques were used to secure the airway definitively by endotracheal intubation. Several difficulties were encountered in the prehospital setting, all of which were dealt with successfully.

CONCLUSIONS

The lack of complications related to rapid sequence induction in prehospital care suggests that this technique is safe when done by A&E doctors on appropriate patients.

Field intubation of trauma patients: complications, indications, and outcomes

Neither the success nor the complication rate for field intubation of trauma patients is known with any certainty. A retrospective audit of 94 severely injured patients who required field intubation was undertaken. Fifty percent (13 of 26) of survivors and 67% (37 of 71) of nonsurvivors were successfully intubated in the field (not significant). Mechanism of injury was similar in both groups, but survivors were younger (27 v 60 years, P= .049) and less critically injured, as reflected by their Injury Severity Scale scores, their Trauma Scores, and their field Glasgow Coma Scale scores (22.1 v 30.8, P = .0035; 7.7 v 4.2, P < .0002; and 6.3 v 3.3, P < .0001). When compared with previously published studies of medical patients with cardiac arrest, the success rate was lower in our trauma patients. When compared with patients having similar injuries intubated at the trauma center, field intubation was three times more likely to be associated with the development of nosocomial pneumonia than was hospital intubation.

Air ambulance trauma transport: a quality review

OBJECTIVE

Provincial air ambulance transports of injured patients were quality reviewed prospectively to determine utilization and appropriateness of care.

METHODS

All trauma air ambulance transports over a 2-month span were reviewed prospectively. Revised Trauma Score, Injury Severity Score, probability of survival, prehospital time, distance of transport, procedures performed, and outcome were determined. Quality control questions were asked of the sending and receiving physicians.

RESULTS

The majority of air ambulance transports reviewed (N = 97) were indicated for mechanism and severity of injury. Economics and requirement for advanced medical care were indications in only 15%. Physicians tended to perform more advanced procedures, likely related to higher patient Injury Severity Score (23 vs. 15, p = NS). Four problems with air ambulance access were identified. The overtriage rate was 5%. Inappropriate patient care was documented in six (6%) cases; a physician was present for only one of these.

CONCLUSIONS

A low overtriage rate was documented, raising concerns that the undertriage rate may be too high. Injured patients air transported without physician accompaniment more often received inappropriate care, suggesting that physician accompaniment is beneficial.