The current study demonstrated that penetrating injuries were more common (82%) among the assault cases in the prehospital setting, and most assaults occurred from sunset to sunrise, especially in the middle of the night. The type of assault and the request-to-contact interval were significant independent risk factors to predict the problem group.
Regarding the type of assault, sharp instruments, such as kitchen knives, were frequently used as means of perpetration, unlike in other countries where firearms and explosives were more frequent [2, 11, 12]. Approximately 20% of victims were injured in the face and back. Based on our experience, it is difficult to imagine that the face is injured in a self-inflicted case even with strong suicidal thought. Similarly, injuring the patient’s back on their own is supposed to be difficult from the position of the hands and back, therefore, they are considered unique features of assault cases. Furthermore, there was more proportion of blunt injuries or fire cases in the problem group. This was presumably because the number of assault cases was only approximately 1% of all dispatches, which meant few opportunities to experience assaults, and voluntarily recognizing blunt trauma as an assault case was difficult because penetrating injuries accounted for > 80% of all assault cases. In fact, except for the world-famous Tokyo subway sarin attack [13], the most common means of recent terrorism in Japan, especially in terms of mass-casualty incidents, were sharp instruments [14, 15].
Moreover, many problem cases occurred with a short request-to-contact interval. Particularly, there is little information about the assault case or the activities of EMTs, police, and other related agencies in case request-to-contact interval is short. Furthermore, such cases mean that time is also running out for these agencies. Especially, the perpetrators may not have been secured, the warning and safety zones have not been established, or even the police have not yet arrived at the scene [2]. This study determined some cases in which the police did not arrive at the scene of the assault. The rush to save lives can lead to a neglect of safety in the medical treatment of such patients with little time to spare, which should be the highest priority [16]. Of the 10 cases in the problem group, seven were treated at the scene while activities at the scene and the rendezvous zone accounted for approximately half the cases. All 14 cases in which the request-to-contact interval was 10 min or less were also treated at the scene of the assault. In some cases, medical care was withheld until the police secured the perpetrator at the scene. Conversely, five of the six problematic cases in which medical personnel approached or had contact with uncaptured perpetrators were handled at the scene. The results suggest that the physician is inevitably more likely to be onsite when the request-to-contact interval is short, and problems due to miscommunication are also more likely to occur. Therefore, a safety declaration by the police does not necessarily guarantee absolute safety; thus, efforts must be made to minimize onsite medical treatment. Cases in which the perpetrator is present as a cooperator who provides patient information are possible, same as in Case 8, 9. Additionally, perpetrators who have committed self-inflicted injury may be mixed in with the other victims, like in Case 1, 2. Sharing advance information from the emergency services and the police regarding the number of perpetrators and whether a weapon has been secured or not, as well as always considering safety, is necessary.
As for future issues, establishing a system in advance with fire and police agencies regarding safety aspects would be desirable. There are organizations that oversees and provides feedback on prehospital emergency care, including EMTs, physician-staffed medical services, not only in the region to which we belong, but also in each medical district. We should constructively discuss the outline of activities for dangerous cases and reach a consensus in the regional organizations. Since 2017, the Kobe City Fire Department has made direct hospital transport the first choice without a request for dispatch of a physician-staffed medical service, when the case is already recognized as an inter-gang case. Regardless of whether conflict or not, discussing and preparing in advance in the region concerned the protocols for information sharing, victim transportation, and security of medical personnel in assault cases is required.
Limitations
This study had several limitations. The first limitation is its retrospective case-control design performed at a single institution in Japan, which is not a gun society. Due to the peculiarities of the case, the sample size was extremely small, even though it was set for a long study period. Furthermore, this study has a small number of cases and missing data. Traffic accidents, crashes, drowning cases, and fire cases may hide cases caused by perpetrated acts. A request for physician dispatch may not have been made in the case of an apparent death that can be determined by EMTs or police. Another major bias is the author’s creation of inclusion criteria for problem cases.