Falls from heights had become a leading cause of traumatic deaths (1). This study investigated the outcomes of patients with free falls in three level-I trauma centers in 10 years. Although the overall mortality rate was 35%, 98% of patients with OHCA were declared death after aggressive resuscitation. By contrast, only 11% of non-OHCA patients died in the hospital. Disparities occurred in the prognostic predictors in patients with and without cardiac arrests. The falling height was associated with OHCAs; a higher ISS was associated with mortality in patients without OHCAs and serious head and chest injuries have a significant impact.
Patients with OHCAs were usually excluded in the previous studies regarding free-fall trauma and little is known about the prognostic factors and injury patterns. The mortality rate would be underestimated with the exclusion of these patients. Hence, the inclusion of the patients with OHCA was essential to better understand the predictors and outcomes among fall-related deaths.
A previous study reported that more than half of the traumatic deaths after falls occurred out-of-hospital (13). In a Taiwanese study, 80% of the fall-related OHCAs failed to survive, whether they were transferred to teaching hospitals or not (14). The survival rates of traumatic OHCAs were significantly lower than those of medical cardiac arrests, although the trauma patients were younger (15). Although the outcomes were better in severely injured patients in level-I trauma center (16), death after aggressive resuscitation was declared for 98% of the patients with OHCAs in this study. It implied that free-fall patients with cardiac arrests did have a grave prognosis, even in trauma centers.
Falls from height is a common major trauma in EDs. The emergency medical services (EMS) system plays an essential role in obtaining important pre-hospital information, such as falling height, place, and cause. Also, because fall-related OHCAs had dismal outcomes, trauma bypass allocating this kind of patient to the level I trauma center should be reconsidered. However, falls often occur in public spaces (15). Obtaining death claims on the scene without transferring to the hospital would be difficult in Chinese society.
Evidence regarding the prognostic factors for free-fall trauma is still controversial. Previous studies have shown that fatal falls were associated with multiple factors, such as older age, falling from a height of more than 6 m, head injury, and higher ISS(2, 5, 6, 9, 17). The results in our study showed that the falling height was significantly related to OHCAs after adjusting for other confounders. The average falling height of cardiac arrests was 22 meters, approximately 6-story height. On the contrary, there was no significant impact of falling height on the outcomes of patients without OHCA.
The ISS was introduced in 1974 (18). It is calculated until all injuries are known, being the gold standard for evaluating trauma patients and a strong predictor of mortality, morbidity, and hospitalization time after trauma (19). Our study demonstrated that ISS was significantly higher among deaths than survivors in non-OHCA patients. To investigate the relationship between patterns of injury and mortality, body regions were included for analysis. Regardless of falling heights, serious head and chest injuries with AIS ≧ 3 were independent predictive factors of mortality. The results implied that low-height falls could cause serious head and chest injuries and even death.
Notably, 16 deaths (52%) occurred in the working place. In a study by Kim et al., those wearing safety helmets were less likely to have intracranial injuries in work-related falls (18). Head injury had a substantial effect on mortality among non-OHCA patients in this study, so helmets were a potentially effective prevention method against work-related traumatic brain injury (18, 19).
Despite these contributions, there were limitations in this study. First, because our study was a retrospective design, some data was missing, such as body position on impact. Second, CT was not performed in patients with OHCAs that patterns of injury could not be elucidated. Third, our results may not reflect the epidemiological profile of the entire population of the whole country. Our hospital and its affiliated hospitals were teaching hospitals where the disease pattern would be more severe and complicated. The mortality rate might be overestimated in this study.