Description of event

The continued perpetration of suicide bombings by terrorists throughout the world requires that knowledge of the topic be continually updated. Global news services and electronic social networking allow terrorists with fundamentalist ideologies to broadcast their extremist views to an international audience. To achieve their heinous goals of killing and maiming as many civilians as possible, they choose to target high-visibility places where the public is concentrated. Hence, they disproportionately attack urban areas such as buses, malls, and restaurants.

Differences have been noted between bombs prepared by terrorists and those used in traditional warfare. Operating on more limited budgets, terrorists have discovered methods of packing bombs with nails, bolts, and other metal objects so as to inflict maximum injury. These bombs are created to be easily transportable, usually strapped to the terrorist’s body. Unfortunately, the ongoing conflicts in places such as Afghanistan, Iraq, and Syria have increased terrorist access to large munitions and resulted in a rapid evolution of suicide bomber tactics, techniques, and procedures (TTPs), such as the use of vehicle-borne improvised explosive devices (VBIEDs) and layered attacks.

Pre-incident actions

Suicide bombing attacks present complex planning and response challenges. Pre-incident actions include planning and preparedness activities generally aimed at threat and consequence mitigation. Social policies addressing the roots of terrorism and the psychological profiling of terrorists are critical components to any full-spectrum policy; however, these topics are beyond the scope of this chapter. This section focuses on two main areas: infrastructure hardening and training.

There are multiple strategies to prevent and mitigate the consequences of suicide bombers. Hardening strategies such as security checks and concrete barriers are now common techniques for limiting suicide bomber access to critical facilities such as airports and government institutions. Barriers erected in vehicle approach lanes and around buildings are designed to prevent detonation in close proximity to critical infrastructure. Hardening of structures may work for many pedestrian or vehicle-borne suicide bombings, but not for all bombings; take, for example, the case of the World Trade Center Bombings on September 11, 2001, by which, due to the combination of a large explosive force and building collapse, most of the victims were killed immediately. In addition, terrorists have adapted TTPs, now deploying teams of suicide bombers to attack barriers in waves (e.g., “layered attacks”).

Training is essential for improved situational awareness and effective response. Planning activities should include yearly drills so that staffs understand their roles in multicasualty incidents, especially those associated with blast injuries. Command, control, and communication need to be emphasized: the Incident Command System (ICS) should be utilized during response. Training should be interagency, including prehospital staff, law enforcement, emergency management, hospital administrators, and relevant clinical/support departments. Anticipating surge capacity in the emergency department, operating room, and intensive care units is essential. All local hospitals need to be included in contingency plans because the number of severely injured patients may be overwhelming, even for a Level 1 Trauma Center.

Post-incident actions

Security is essential at the scene of the event, as well as at the hospital. There have been numerous instances of secondary bombings where an additional intentional device or bomber detonated after prehospital providers entered the scene. This resulted in rescuers then becoming victims. Rescue teams of emergency medical service(s) (EMS) and fire department personnel will naturally assume higher risk than daily operations, but they must work closely with police or security services to ensure appropriate levels of “scene safety” before they enter a scene and begin resuscitation and rescue efforts. Hospitals are vulnerable targets, and staff must remain vigilant after a suicide bombing. Health care facilities are notorious “soft” targets, often lacking armed security and proper blast hardening or mechanisms to effectively limit bomber access.

Blast injury patterns have classically been described based on wartime injuries, with a limited number of survivors requiring medical care. In contrast, urban bomb explosions result in many patients arriving alive at the hospital but with devastating injuries. Terrorists know that maximum death and injury can be accomplished by bringing the explosives to closed spaces. There is a direct correlation between the location of the blast and survivability. Open, closed, and sealed spaces result in differential injury patterns based on the standard categories of blast injury. ^, Mortality is the highest in ultraconfined spaces such as buses. In general there is a higher injury-severity score for those presenting to the hospital following terrorist attacks than those presenting because of other trauma. Surgical interventions are higher in these patients as well.

The classification of blast injuries is discussed in length in other sections of this text ( Box 72-1 ). Given the suicide bomber TTP of seeking close proximity to victims, there are some issues particularly relevant to suicide bombings. Virtually all patients exposed directly to the blast front will incur primary blast injury. The immediate blast front is dissipated from the center of the explosion based on forces of spalling, acceleration, and implosion mechanisms, as well as pressure differences. Air-containing structures such as the lungs, bowels, and tympanic membranes are often affected. More than 50% of patients exposed to a blast of greater than 15 to 50 psi will suffer tympanic membrane perforation. This can be a marker of coincident injuries such as a blast lung injury (BLI) that may not be readily apparent (BLI often requires higher pressures of 50 to 100 psi). Primary blast head injury appears to have a higher mortality compared with other conventional head injuries, most probably because of the tremendous force of the initial exposure. Air emboli in the pulmonary and coronary vessels may also be a cause of death.

Secondary blast effect results from flying shards of metal, glass, and other explosive objects that inflict injuries similar to those from classic penetrating patterns. Given some limitations in the volume of explosives that suicide bombers can carry, they have historically utilized high volumes of adulterants such as metal bolts, nails, and pellets. As a result, benign appearing skin wounds may signal severe underlying injury. Suicide bombing also significantly increases the risk of biologic foreign body implantation secondary to flying bone fragments from the suicide bomber, other victims, or the patient.

Infiltrates on chest x-ray often present a clinical challenge because it may be difficult to differentiate between BLI and lacerated lung caused by secondary blast mechanisms. Both may present as a pneumothorax, but a hemothorax is less common in classic blast injury. Both may also develop significant respiratory difficulties, with persistent air leaks requiring creative ventilator techniques. However, in the early phase of injury, fluid management is different because blast lung requires restrictive management and is nonoperative, whereas lacerated lungs need fluid resuscitation and often surgical repair. ^,

Tertiary blast effects, causing the victim’s body to be thrown, are accentuated in closed and ultraconfined spaces because the victim’s body may be propelled against stationary objects by a supercharged blast front. Immediate amputation or death can occur. Quaternary blast injuries are burns caused by the explosion itself or surrounding flammable area. These may include all types of classical burn injuries, including inhalation, chemical, and contact burns.

Often the patient suffers from a combination of blast injury effects including blunt injury, penetrating trauma, and burns. This is known as the multidimensional injury pattern and is unique to bomb explosions. ^, Particularly challenging are visceral blast injuries that may occur from multiple wounding mechanisms. Primary or tertiary blast injury may cause slow dissection along tissue planes, resulting in delayed peritonitis. In contrast, missile trajectory of secondary blast injury may parallel classic penetrating injury resulting from stab or gunshot wounds.