Despite the increase of IED attacks in present zones of conflict, rockets and mortar fire also remain common mechanisms of injury. In the author’s experience, injuries due to these weapons most often result in superficial injuries that in most cases require only wound debridement and local care. Many of these types of injuries appear horrific on initial review, with multiple fragmentation injuries covering the entire side of a body. Although appropriate vigilance demands comprehensive evaluation in all of these cases, we have found that in most instances, those who survived to reach treatment had injuries confined to the soft tissues and most often did not penetrate a body cavity. The evaluation and treatment of these injuries should, however, be based on careful examination of each and every single fragmentation injury. The use of radiographs can be used to identify the multiple foreign bodies (Fig. 71.3). Determining intracorporeal penetration remains a challenge, and in the battlefield scenario, body cavities often have to be surgically explored. On occasion, fragmentation injuries are also accompanied by burn wounds. Fortunately, in most instances, these burns were relatively minor. Despite our experience, we continue to recommend that a high index of suspicion be exercised in all cases of fragmentation injury (Fig. 71.4). Fragments can be of all types (Fig. 71.5), and this includes dirt, rocks, and bone from other casualties.

Tertiary blast injuries occur when the casualty is thrown by the blast wind. This can cause superficial wounds and fractures. Amputation from tertiary blast is not common. Solid organ injuries can occur but were rarely seen in the authors’ experience.

Quaternary blast injuries include flash burns. Although temperatures from explosions can reach up to 3,000 °C, the rise in temperature is rapid and so is the decline in temperature as the fuel is quickly expended. A common example of this type of injury is a propane explosion in a trailer home. These types of flash burn more commonly affect the exposed skin. A classic scenario is of a male patient who is minimally clothed in jeans or shorts attempting to light the propane stove after the pilot light has extinguished. Since propane is heavier than air, an enclosed room can fill with propane. If the smell of the accumulating gas is not detected when a match or lighter is ignited, disaster is likely to ensue. In contrast to propane, natural gas is lighter than air and will rise. Subsequently, in a flash explosion of natural gas, curtains or furniture may catch on fire and contribute to the creation of toxic fumes. Inhalation injury occurs if the casualty is in a closed space and there is a concomitant fire. Any fire on clothing or surrounding structures such as parts of a vehicle may result in significant partial or full thickness burns.

Quaternary blast inhalational injuries may also exacerbate underlying asthma or chronic obstructive pulmonary disease. The classic dangers of quaternary injury are from falling debris, from buildings, for example. Such debris can cause direct crush injury and cause compartment syndrome and myoglobinemia. These types of injuries may prove common after terrorist attacks on buildings with VBIEDs.

The mortality from bombings is classically triphasic. Immediate mortality from disruption of bodies, chest injuries, head injuries, or rapid exsanguination is the most common. Some immediate deaths will have no external signs of injury, succumbing instead to catastrophic air emboli or fatal cardiac dysrhythmias. The mortality among casualties surviving to reach treatment is lower. It is also important to consider the environment in which the explosion occurs since it may significantly affect the cause of mortality. Explosions in open space tend to produce more secondary blast injuries, whereas those occurring in enclosed spaces are more likely to produce primary, tertiary, and quaternary injuries. This rationale likely explains the reason for the injury patterns observed in Iraq and Afghanistan, which are largely penetrating secondary blast injuries that occur in open spaces. Similar patterns have been observed in recent civilian terrorist events.