“In The Right Back”

Most gunshot scenes are quite bloody. Some scenes show evidence of considerable bleeding; some essentially none. In the latter case, hemorrhaging is internal (into the chest or abdominal cavities) or is prevented by clothing. The only observable blood may be a dime-shaped area of bleeding on the clothing overlying the entrance site. Minimal bleeding around an entrance site usually involves small-caliber. Clothing may act as a pressure bandage. When the deceased is wearing multiple layers of clothing, blood from the wound may be absorbed by the internal layers of clothing so that there is no evidence of bleeding on the outer clothing. Gunshot wounds of the head usually bleed freely. This is not invariable, however. The author had a case in which there was a contact gunshot wound of the back of the head from a .22-caliber rimfire weapon whose entrance was sealed by the hot gases. There was no blood at the scene or visible on the body. The entrance was concealed by a bushy haircut and was found only when the head was opened as part of a routine autopsy on an apparent natural death. The quantity of bleeding, however, is very variable. When the oxygen in the brain is consumed, unconsciousness occurs. Experiments have shown that an individual can remain conscious for at least 10 to 15 sec. after complete occlusion of the carotid arteries. Thus, if no blood is pumped to the brain because of a massive gunshot wound of the heart, an individual can remain conscious and function, e.g., run, for at least 10 sec before collapsing. Sudden blood loss causes interference with activity when it exceeds 20 to 25% of the total blood supply. Loss over 40% is life threatening. The rate of bleeding, the amount of blood loss, the nature of the injury, and the body’s physiological response determines the time from injury to incapacitation and death. This can vary from seconds to hours. As blood is lost, there is impaired perfusion of the tissue by blood with resultant cellular dysfunction (shock). The individual becomes anxious, weak, disoriented and restless. The pulse becomes weak, blood pressure falls, and breathing becomes rapid. The body initiates defensive mechanisms to counteract this loss of blood. Blood pressure (and thus tissue perfusion) is directly related to cardiac output and systemic vascular resistance (primarily the vasomotor tone of the blood vessels in the peripheral vascular system). As blood pressure falls, there is activation of the systemic nervous system. Epinephrine (adrenalin) and norepinephrine are released from the adrenals and sympathetic nerve endings. B1 receptors in the heart respond by increasing the heart rate and force of contraction. This results in an increase in cardiac output. Stimulation of A1 receptors in the peripheral vasculature causes selective vasoconstriction reducing the blood flow to the skin, gastrointestinal tract and kidneys, thus maintaining adequate perfusion of the heart and brain. The decease in arterial pressure also causes a decrease in the capillary hydrostatic pressure. As this falls, fluid from the interstitial space is drawn into the vasculature replacing the volume of the lost blood. Once the blood loss exceeds the ability of the body to compensate, there is confusion, disorientation and loss of consciousness. Numerous individuals have survived perforating gunshot wounds of the frontal lobes though there may be associated personality changes and/or blindness. In documented cases of suicide, individuals have fired a bullet through the frontal lobes, to be followed by a second, fatal gunshot wound, of the basal ganglia.

In one case, an elderly individual shot himself in the temple with a .32-caliber revolver. The bullet perforated both cerebral hemispheres injuring the tips of the caudate lobes. Following this, he was conscious for at least two hours during which time he spoke to his wife, a visiting nurse, and EMS personnel.

Gunshot wounds of the brainstem produce instant incapacitation, though death may not occur immediately. One individual who had a gunshot wound of the pons survived approximately one week, although in a totally vegetative state. Emergency room physicians often miss head wounds because of long hair and back wounds because they fail to look at the patient’s back. They also confuse entrances with exits. The failures involved errors in interpreting the number of projectiles as well as differentiating exits and entrance. One must approach medical records with a degree of caution in trying to determine how many times a person has been shot as well as whether a wound is an entrance or exit. A gunshot wound may be described only as “in the right back” without any other localizing information. Occasionally, such information may be found in the nurse’s notes. One must also realize that soot may have been present initially, but that the nurse who saw the patient before the physician may have wiped it off. These factors again point out the importance of retention of clothing, as the wounds in question may have been due to bullets that went through the clothing. The ambulance crews, emergency rooms, and hospitals should be instructed never to discard clothing in cases of gunshot wounds. In gunshot wounds of the chest, the surgeon may insert a chest tube into the wound or make his thoracotomy incision through it. In gunshot wounds of the head, it is usual for the surgeon to obliterate the entrance wound in the scalp and bone when performing a craniectomy. Unfortunately, it is not uncommon for a surgeon to inscribe their initials on the side of a recovered bullet rather than the nose or base, thus obliterating its rifling characteristics. In shotgun wound cases, one should also inform the surgeons that the wadding and representative pellets should be retained for evidentiary purposes. Advanced decomposition may also conceal a gunshot wound. The use of x-rays on select decomposed bodies will prevent missing such cases. Skin differs from other tissue in that a relatively high initial velocity is necessary for a bullet to effect perforation. Knowledge of this velocity is important to the forensic pathologist in cases of assault, attempted homicide, or homicide with airguns as well as in determining the maximum range out to which a bullet is capable of penetrating the body. The increased loss of velocity in passing through the skin compared with the solid lead bullets is consistent with the increased loss sustained while passing through muscle. Vascular embolization of a bullet is an uncommon occurrence. When it does occur, it usually involves the arterial system. The most common sites of entrance for a bullet into the arterial system are the aorta and the heart. Bullet emboli are usually associated with small caliber, low-velocity missiles. If an x-ray is not taken before autopsy, a bullet embolus secondary to a gunshot wound of the aorta may not be suspected because of the presence of both an entrance and an exit in this vessel. In such a case, the almost spent bullet, after exiting the aorta, strikes the vertebral column and rebounds back through the exit into the lumen of the aorta, where it is swept away to a lower extremity. A variant of the bullet embolus not involving vascular embolization is occasionally encountered. One such case involved an individual shot in the right back. The bullet traveled upward into the oral cavity, where it subsequently was coughed or vomited up by the victim. The bullet was found on the ground a number of feet away from the deceased in a pool of vomitus and blood. In another case, an individual incurred a gunshot wound of the chest. On admission to the hospital, the bullet was seen on x-ray apparently lodged in the parenchyma of the right lung. The individual survived a number of days in the hospital. At autopsy, the bullet was found in the bronchus of the left lung. Apparently the bullet entered the bronchial tree on the right side and subsequently was coughed up and aspirated into the left bronchial tree. Gunshot wounds of the brain constitute approximately one-third of all fatal gunshot wounds. Wounds of the brain from centerfire rifles and shotguns are extremely devastating. When a bullet strikes the head, it “punches out” a circular to oval wound of entrance in the skull, driving fragments of bone into the brain. The bone chips generally follow along the main bullet track, contributing to its irregular configuration. Sometimes the bone chips create secondary tracks that deviate from the main path. These chips are detectable on digital palpation in approximately one-third of gunshot wound cases of the brain. As the bullet perforates the brain, it produces a temporary cavity that undergoes a series of pulsations before disappearing. The pressure waves in thebrain in the case of high-velocity missiles may produce massive fragmentation of the skull. In the case of handgun bullets, the pressure waves are considerably less but still may cause fractures. Linear fractures of the orbital plate are the most common because of the paper-thin nature of the bone. Fracture lines may radiate from the entrance or exit hole or even be randomly distributed in the vault or base of the skull. No matter what the caliber, secondary fractures are more common with contact wounds, where the pressure waves from the temporary cavity are augmented by pressure from the expanding gas. Distant wounds are more likely to produce penetrating wounds rather than perforating wounds; contact wounds, perforating rather than penetrating. A bullet entering the skull through the thick occipital bone is less likely to exit than a bullet entering through the thin temporal bone.

Examination of the brain in gunshot wounds reveals contusions around the entrance site in about half the cases. These are probably due to inbending of the bone against the brain at the moment of perforation. Contusions are equally frequent at the exit, although they do not necessarily occur in the same cases as entry contusions. Contusions can also be seen on the inferior surface of the frontal lobe. The brain will show signs of increased intracranial pressure. These signs consist of grooves of the uncal gyri from the tentorium as well as cone-shaped molding of the cerebellar tonsils at the foramen magnum. These findings may help explain death in some cases. Examination of gunshot-wounded brains reveals many cases in which the vital centers were not directly in the path of the bullet and in which the volume of the permanent cavity was relatively small (less than many spontaneous hematomas), i.e., the volume of grossly involved brain is trivial when compared with the brain itself. In such cases, deformation of the brain toward the foramen magnum still occurs. Pressure on the brainstem secondary to this deformation may be the fatal mechanism in these cases. Gunshot wounds of the pregnant uterus are relatively uncommon. Maternal death in such cases is rare. The gunshot injury to the fetus or placenta usually results in intrauterine death or premature delivery with or without evidence of injury to the child. The most significant question arising from fetal deaths due to gunshot wounds of the pregnant uterus concerns the ruling of the manner of death.

“…If the child dies in utero, no matter how advanced the state of development, there is no criminal culpability for the child’s death attached to the person who did the shooting. Legally the child is not considered an individual until it is born alive….”

If, however, the child is born alive and then dies, even if the time of survival is a matter of only a few minutes, the death is considered a homicide, even if the bullet did not strike the child but just induced premature labor. In the latter case, one could rule the cause of death as “Prematurity secondary to gunshot wound of uterus — Homicide.”

Smokeless powder is used in all modern cartridges. When it is ignited in a gun, heat, and gas are produced, both of which are confined initially to the chamber. As the pressure of the gas builds up, the chemical processes of combustion are speeded up so that the rate of burning becomes relatively instantaneous, and an “explosion” is produced. This explosion, however, occurs only when smokeless powder is ignited in a confined space such as the chamber of a gun. Outside of a gun, the powder will only burn with a quick hot flame. Black powder is a different matter. It burns faster than smokeless powder and may actually produce an explosion. Black powder is not loaded in modern ammunition. After a minute of heating, the can exploded with a heavy dull thud, producing a dense cloud of smoke but no flames. The can was hurled approximately 35 ft. It had been opened up and flattened by the explosion.

Occasionally one hears that an individual has been “wounded” when a cartridge was accidentally dropped into a fire and detonated. Investigation of such incidents usually reveals that the victim was really injured when they or another individual was playing with a gun. When small-arms ammunition is placed in a fire, the cartridge case may burst into a number of fragments and the bullet may then be propelled forward out of the case. In centerfire cartridges, the primer may blowout. None of these missiles, however, is dangerous to life under ordinary circumstances. The bullet in fact is probably the most harmless of all these missiles because with its relatively great mass it will have very little velocity. Fragments of brass and the primer are the only components of an exploding round that have sufficient velocity to cause injury. Occasionally a firearm will be used not only to shoot a person but to beat that individual. Thus, individuals will be seen with evidence of “pistol whipping.” This usually takes the form of semicircular or triangular lacerations of the scalp or forehead produced by the butt of the gun.

Acknowledgements:

The Police Department;

www.politie.nl and a Chief Inspector – Mr. Erik Akerboom     ©

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