(^212) Medical-Surgical Nursing Demystified
Just the Facts
Head Injury
WHAT WENT WRONG?
The patient experiences a trauma to the head. The resulting injury may be a minor
scalp laceration or a major internal injury with or without a skull fracture. There
may be internal hemorrhage or cerebral edema resulting in hypoxia and a decrease
in cognitive and functional capabilities. There are a variety of injuries that may be
sustained. Open head injuries are typical of projectile wounds from gunshots or
knifes. Closed head injuries are typical of trauma from falls, motor vehicle acci-
dents, sports, or fights.
Concussion involves a blow to the head where there is a bruising-type injury as
the brain is thrust against the inside of skull. The point of injury where the brain
makes impact against the skull is referred to as a coup injury. There is also a con-
trecoup injury as the head recoils away from the point of impact and the brain is
thrust against the inside of the skull at the opposite point of the head, resulting in
injury there as well. Patients with concussion may experience a transient loss of
consciousness associated with bradycardia, or slowing of the heartrate; low blood
pressure; slow, shallow breathing; amnesia of the injury and the events immedi-
ately following the injury; headache; and temporary loss of mental focus. Cerebral
contusion is a more serious injury than concussion. Greater damage is done to the
brain; cerebral edema or hemorrhage may occur and lead to necrosis. Patients typ-
ically have longer loss of consciousness with a cerebral contusion.
Hemorrhages can occur at a variety of levels, between the skull and the outer
coverings (dura) of the brain, within the layers covering the brain, or within the
brain tissue. The bleeding may occur acutely, at the time of injury, or hours to weeks
later. An epidural hematoma happens at the time of injury from an arterial site. The
blood accumulates between the skull and the dura mater, or the outermost layer
covering the brain. The site is often in the temporal area. The patient is typically
awake and talking immediately after the blow to the head. Within a short time, the
patient becomes unstable and then unconscious. Emergency neurosurgery is neces-
sary to relieve the pressure and stop the bleeding. Subdural hematoma is typically
bleeding from a venous source into the area below the dura mater and above the
arachnoid mater. This may occur acutely in some patients, but can also occur as
a slow, chronic bleed, especially in the elderly patient. The elderly patient with a
chronic bleed may have a significant amount of blood accumulate before symptoms
occur due to age-related changes in volume of brain tissue. A subarachnoid hemor-1