Ballistic trauma

Overview
The term ballistic trauma (generally referred to by the type of weapon; gunshot wound, etc.) refers to a form of physical trauma sustained from the discharge of arms or munitions during conflict or otherwise. The most common forms of ballistic trauma are those which stem from small arms fire, namely semi-automatic pistols, light machine guns, sub-machine guns and assault rifles used in armed conflicts, civilian sporting and recreational pursuits and illegal activity.

In terms of public health, it is estimated that over 500,000 injuries are sustained annually from the use of firearms; 300,000 or more relating to those occurring in situations of armed conflict, with the remainder of 200,000 or more being sustained in non-conflict situations. According to reports from the World Health Organization in 2001, these injuries represent roughly a quarter of the estimated 2.3 million deaths which have occurred due to violence ; 42 % being suicides, 38 % homicides, and 26 % related to war and armed conflict.

Introduction
Although there are several causes for ballistic trauma depending upon the situation in which they occur, priorities for physicians lie in ascertaining the likelihood of survival for the patient based upon damage caused by the bullet on entry – whether a bullet strikes or shatters a bone, and if shattered bone or shrapnel has punctured vital organs or has damaged the spinal cord of the patient. Alongside estimation of the patient's survival, another key determinant is if the future health of the patient dependent upon the severity of the injury so that preventative measures can be approximated, due to the benefits of preventing death or injury outweighing those of a purely treatment-based approach.

Alongside physical and medical measures used to prevent injury and death, there are two main approaches of harm reduction and public health. The perspective of harm reduction operates under the premise that by their very nature, arms and munitions are entities which are used to kill, harm or threaten other beings which translates within most modern societies as the reduction of harm rather than their banning in entirety due to their utility within society. The latter public health perspective on firearms centers around scientific approaches to illustrating and examining issues and ultimately the causal factors of firearms injuries including other routes, such as psychological, criminological, economical and educational means.

Assessment of severity
When assessing the likely severity of gunshot wounds, there are numerous variables which include the following, considered either singly or in concert:


 * the particular type of weapon used; rifles are generally more destructive than handguns. For example, a close-range abdominal wound inflicted by a G3 rifle will be much more severe than one inflicted by a .38 revolver from the same distance.


 * the calibre of the weapon; e. g. a wound from a .22 handgun will generally be less severe than a wound inflicted by a .357 Magnum handgun.


 * the design of the bullet used and its propellant charge i. e. a standard velocity 9mm FMJ bullet is generally less destructive than a high velocity 9mm hollowpoint bullet.


 * the range at which the victim was shot; i. e. wounds inflicted by 7.62x39mm bullets fired from a distance of 5 metres will invariably be more severe than those fired from a range of 500 metres. The velocity of a bullet (and therefore its destructive potential) gradually reduces as it travels from the muzzle of a firearm.


 * the site of injury. For example, though serious, a gunshot wound to the buttocks is unlikely to be fatal, unless the femoral artery is severed. This is in marked contrast to a gunshot wound to the side of the head which penetrates both cerebral hemispheres: such a wound is almost invariably fatal.


 * the number of wounds inflicted. Frequently, gunshot wound victims have been hit multiple times. For example, while a .22 calibre bullet is one of the less destructive bullets used, it is an entirely different matter if someone were to suffer ten separate abdominal wounds inflicted by this particular calibre. In much the same way, an individual shotgun pellet is comparatively small, though since victims are usually hit by large numbers of pellets simultaneously, the degree of injury is severe, particularly when the wound is inflicted at close range.

It is important to emphasize that non-fatal gunshot wounds often have severe and long-lasting effects, even after the victim has made a successful recovery. Typically, the consequences involve some form of major disfigurement and/or permanent disability. As a rule, all gunshot wounds are medical emergencies which require immediate hospital treatment.

Destructive effects
The immediate damaging effects of the bullet are typically a loss of blood, and with it, the potential for hypovolemic shock, an inadequate amount of blood in the circulatory system. More immediate effects can result when a bullet strikes a critical organ such as the heart or damages a component of the central nervous system such as the spine or brain. Common causes of death following gunshot injury include exsanguination, hypoxia caused by pneumothorax, heart failure and brain damage. Non-fatal gunshot wounds can result in serious disability.

Gunshot injuries can vary widely from case to case since the location of the injury can be in any part of the body, with wide variations in entry point. Also, the path and possible fragmentation of the bullet within the body is unpredictable. The study of the dynamics of bullets in gunshot injuries is called terminal ballistics.