Trauma is a major cause of death and social problem.1 In low and middle income countries, which make up 85% of the world, 11% of all disability-adjusted life years are due to trauma.2 In these countries, trauma-related mortality before 70 years of age is more frequent than in high income countries, and the life expectancy projections are very low.3 Also, according to the Annual Report of Emergency Medicine in Korea, the proportion of trauma patients have steadily grown, and the overall mortality of trauma patients in emergency centers have gradually increased from 1.87% in 2007 to 2.71% in 2011.4 For these reasons, major attention is given to improving treatment of trauma patients, preventing trauma itself, and developing various emergency medical services to reduce preventable trauma death. Particularly, understanding the epidemiology of trauma helps to analyze risk factors, to develop treatment strategy, to reduce disability, to prevent mortality, and to construct a precise intervention system. However, the lack of trauma epidemiology data limits the growth of these trauma management systems.5,6

The purpose of this study is to examine the epidemiology of trauma within a local community in Korea through data gained from one emergency center and to analyze trauma patients in order to find the predictors that led to the deaths of trauma patients.

All data were based on patients registered on the trauma registry at the emergency center of Wonju Severance Christian Hospital, located in Wonju city, Gangwon province, Korea. The aforementioned center is run on national funds and is composed of emergency physicians, trauma surgeons, trained nurses, and clinical research coordinators. When patients are admitted to the emergency center, patient information such as age, gender, address, and method of admission is gathered; additionally, clinical information such as mechanisms of injury, the time of injury, revised trauma score (RTS), injury severity score (ISS), major injury site, history of hospitalization and surgery, transfer history, and death on arrival (DOA) is composed in detail. The major injury site is determined by the highest abbreviated injury score (AIS) among the measured areas or the area that led to death or admission. It is divided into subgroups: craniocerebral, thoracic, abdominopelvic, and extremity. The information was constantly updated in order to assess each patient's progress. To ensure the accuracy of the data, confirmation by the trauma surgeon and senior doctors took place before they were entered into Excel (Microsoft, 2005).

The trauma registry data had been collected since January 1, 2010, and 21697 patients were registered from that time until Dec 31, 2012. Cases relating to poisoning, burns, drowning, and suicide were excluded, leaving 17007 selected patients, who were examined retrospectively and approved by the Institutional Review Board of Wonju Severance Christian Hospital (YWMR 14-5-001).

All statistical calculations were performed using SPSS version 20.0 (SPSS Inc., Chicago, IL, USA). The frequencies for variables were identified using descriptive statistics. Student's t-tests, or non-parametric tests when necessary, were employed for quantitative variable analysis, and Pearson chi-square tests were used for categorical variable analysis between survivors and non-survivors. Multivariate analysis and identification of the independent factors associated with trauma mortality was achieved through the adjustment of a logistic regression model. Only the variables associated with mortality that yielded p values lower than 0.5 in the initial analysis were input into the logistic regression analysis. Odds ratios and 95% confidence intervals were used to estimate the associations with non-survivors.

Mortality and morbidity rates for diseases in Korea have gradually decreased due to the development of medical technology, national interest in healthcare, and the enhancement of antibiotics and surgery techniques. However, the development of faster transportation and expansion of leisure activities in Korea have caused a sharp increase in the number of trauma cases. Moreover, Korea's rapid industrialization has led to an increase in injuries caused by people falling or by objects crushing or penetrating the body at industrial sites.7

In considering other studies, motor vehicle accidents and injuries from falling seem to occur more often with men than with women, as stated by WHO3 and Moshiro, et al.8 Such can be inferred by the more prominent social activities of men in comparison to those of women, and as a result, men are more prone to vehicle and work related accidents. Fig. 1 shows the three-point-peak progress for those of ages 10 or younger, 21-50, and 61 or older. It can be presumed that trauma under the age of 10 is dominated by the carelessness of children, whereas trauma between the ages of 21 to 50 is dominated by an increasing number of motor vehicle accidents or work related accidents. It can also be inferred that the increasing trauma after the age of 61 is due to the weakening of the body and lack of attentiveness. The distribution of trauma according to age shown in this study is similar with that of other studies.9,10

Of the total number of patients who visited the emergency center, 56.0% of patients were discharged by the emergency physician after primary treatment. This phenomenon may be attributable to the well-developed health insurance system in Korea, which allows for visits to easily accessible emergency centers at a relatively low cost; thus, our trauma registry contained more minor trauma injuries than other data.11 Although some trauma patients required hospitalization at the emergency center, 15.6% of these patients opted to transfer, as they lived in different region or wanted to move to more renowned hospital. Such cases are due to the distinct features of the region in which our hospital is located, given the surrounding area is ideal for holiday trips and leisure activities; there are also few general hospitals and university-affiliated hospitals in the province. Therefore, when accidents occur, regardless of where the patients originally came from, the primary care is carried out by our emergency center. Furthermore, there is an unusual behavior common to many Koreans to tend to transfer to famous general hospitals in the metropolitan region.

Most of the trauma mechanisms in our data were classified as blunt trauma, slip-and-fall-down injuries, and vehicle related accidents (90.8%). Similarly, slip-and-fall-down injuries and vehicle associated injuries tend to be dominant, as stated by Bulut, et al.12 and Lallier, et al.13 Motor vehicle accidents are among the highest leading causes of death and disability and are a major cause of trauma patients in public health. Drunk driving, drowsy driving, and careless driving are several examples of the causes of motor vehicle accidents, and all of them are prominent in young men and women in general.14,15 Slip-and-fall-down injuries are also among the highest leading causes of blunt trauma; these types of injuries are caused by carelessness or suicidal intentions.16,17 The injury mechanisms mentioned above are health problems that can definitely be prevented by safety education by promoting a safe environment and continuing health education.

Globally, trauma is one of the major causes of death and is especially prominent at a young age.18,19 The first research on death by trauma is a paper written by Baker, et al.20 in 1980 on the epidemiology of death by trauma in San Francisco. According to the results presented in more recent papers, an annual 5.8 million deaths are caused by trauma, and in 2020, this figure is expected to rise up to 8.4 million deaths annually.21 When looking at WHO data from 2007, deaths caused by trauma constitute 9% of total annual deaths.22 Excluding in-hospital deaths in our data, early trauma mortality was 3.0% (146 of 4815 patients). Additionally, overall mortality was 5.6% (268 of 4815) among admitted patients. The results are similar to those of Sogut, et al.23 (4%) and Sanddal, et al.24 (7%). When the data from our hospital was organized by major cause of death, craniocerebral injury accounted for 42.2% of deaths, thoracic injury accounted for 33.6%, and abdominopelvic injury accounted for 24.2%. This is similar to data collected from trauma patients who expired after hospitalization; Sogut, et al.23 stated that 84% of total patients had craniocerebral injuries (p<0.01) as accompanying damage, and 43.5% died of thoracic injury (p<0.01). However, that study involved multiple response data, while our data checked only the most severe single injury that led to death.

Also, in our data collected from non-survivors, we found that the highest ISS for thoracic injury was 27.3±10.1. This score compared thoracic injury to other injuries and was statistically high in non-survivors. However, in contrast to the high ISS score for thoracic injury, Table 3 shows that major thoracic injury was the least common injury. In most accidents, patients were vulnerable to head trauma, increasing the possibility of craniocerebral injuries and severe outcomes. Moreover, although there was a high rate of abdominal injuries due to the soft abdominal wall and the susceptibility of solid organs to undergo sudden acceleration and deceleration, the development of damage control surgery, advanced resuscitation, swift angiography, and less invasive techniques have lowered the mortality rate of abdominal injury. Generally, craniocerebral injury does rank highest among causes of death by trauma; however, thoracic injury also ranks high with 25% mortality and constitutes 50% of fatalities of all traffic accidents,25 thus holding significance and requiring a high degree of attention in patients with major thoracic injuries. However, excluding trauma deaths, many thoracic injuries are of moderate severity due to the stiffness of the thoracic cage and few solid organs. Additionally, most thoracic trauma is treated conservatively with tube thoracostomy and rarely requires surgical intervention.26 This explanation reveals why the number of major thoracic injury patients were small in our data. In the past, trauma in Korea was merely a part of a wide range of surgical fields; however, many general surgeons have recently specialized in trauma and have made efforts to increase survival with prompt life-saving surgery, such as damage control surgery. Yet due to high craniocerebral and thoracic trauma mortality rates, neurosurgeons, thoracic and cardiovascular surgeons, and even orthopedic surgeons must concentrate on trauma dominantly, and these certified trauma surgeons are essential in supporting a multi-disciplinary trauma team approach in the emergency center to decrease trauma mortality rates.

Tan, et al.27 revealed that increasing age was a risk factor for mortality after trauma, and Agalar, et al.28 states that trauma mortality has significant relations with age, ISS, and revised trauma score. In our study, ages ≥55, ISS ≥16, major craniocerebral injury, CPR at arrival, and Ps <25% from TRISS were independent risk factors for trauma mortality. Old age, ISS above 15, and severe craniocerebral injury have already been established as predictors of mortality.23,26,27 Furthermore, CPR at arrival and Ps from TRISS lower than 25% can be easily predictable factors for trauma mortality. According to Ps values calculated from TRISS, our center showed 27.6% mortality in those with a survival probability of more than 75%. This finding may be explained by the fact that about half of deaths occurred in-hospital, and although most died due to the trauma, some suffered trauma-related complications such as septic shock, pneumonia, or acute respiratory distress syndrome in the treatment period, which may have contributed to the increase in mortality despite the high probability of survival. Unusually, the interval from accident to arrival at the emergency center was longer in survivors than non-survivors, differing from the results of other data.23 Most life-threatening patients were transported to our emergency center directly; however, some vital-stable patients were transported to our emergency center from other local hospitals after physical examinations, laboratory tests, and image studies. Although some critical patients were originally taken to local hospitals, after image or laboratory studies, they were transported to our emergency center for further definitive treatment. This delay in arrival is the result of a lack of education in patient triage when at an accident location. Continuous education of proper transportation for emergency transport systems will shorten this delay.

The authors intend to improve treatment and prevent of trauma death by analyzing the results of treatments and causes of trauma-related deaths. In order to enhance the quality of treatment for severe trauma patients, regional trauma centers have been designated and are currently being built in Korea. However, in addition to the need for the development of such trauma centers, software is also required to improve rapid transport, rapid sequence management, effective trauma team approaches (involving general surgeons, thoracic and cardiovascular surgeons, neurosurgeons and orthopedic surgeons), and constant education. Additionally, a shared trauma registry system for epidemiology is required, which will improve the quality of trauma centers; however, the data collection must be standardized, valid, and reliable.

One of the limitations of this study is that the study was not carried out in multiple centers but was limited to one regional emergency center for 3 years; thus, the sample and term were somewhat limited. Also, patients who were dead on arrival and those who expired during CPR should have been considered for major trauma outcome studies taking into consideration autopsy results, operation opinions, and radiation diagnoses; however, autopsy in Korea is very confined, and though limited, causes of deaths have been revealed by doctors of emergency departments and trauma surgeons in discussion. One final limit is the fact that deaths outside of the emergency center such as discharge against advice have not been accounted for in this study.

In conclusion, our results show that injuries of trauma patients are caused mainly by blunt force, falls, and motor vehicle accidents. Major injury sites were on the extremities of most trauma patients. Additionally, the most common cause of trauma mortality was craniocerebral injury. However, the mean ISS of trauma death for thoracic injury ranked high. Finally, ages ≥55, ISS ≥16, severe craniocerebral injury, CPR at arrival, and low Ps (<25%) from TRISS were associated with trauma-related death and require careful surveillance in order to identify patients who are vulnerable to death. Finally, rapid transport, rapid sequence management, effective trauma team approaches, constant education, and a standardized trauma registry may decrease trauma-related deaths.