Head Injury

Introduction:

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-
rhage causes blood to accumulate within the area below the arachnoid mater and
above the pia mater. The cerebrospinal fluid is found in this area. An intracerebral
bleed is an accumulation of blood within the tissues of the brain. This may be due
to a shearing force on the brain tissue from a twisting motion between the upper
part of the brain (cerebrum) and the brain stem or tearing of small vessels within
the brain. There will be associated edema and elevation of intracranial pressure.
Simple skull fractures are displaced and do not require specific intervention.
Depressed skull fractures have bone fragments that have been broken off from the
skull and pressed down toward the brain tissue. These fractures need to be cor-
rected surgically. A basilar skull fracture has classic signs that include periorbital
bruising (raccoon sign), blood behind the ear drum (Battle’s sign), and leaking of
cerebrospinal fluid from the nose or ear (check for glucose content to distinguish
from a runny nose).

PROGNOSIS
The prognosis following head injury varies greatly depending on the location of
the injury, the severity of the damage that occurred, and the treatment that was
received. Patients with loss of consciousness over 2 minutes have a more severe
injury and therefore worse prognosis. Patients who have loss of memory, either
about the incident or the events immediately following, also have a more severe
injury and worse prognosis. Some patients develop hemorrhage as a late effect of
head injury, occurring hours, or in some cases, days after the initial injury. Post-
traumatic seizure disorder can also occur as a late effect of head injury.

SIGNS AND SYMPTOMS

• Headache due to direct trauma and/or increasing intracranial pressure
• Disorientation or cognitive changes
• Changes in speech
• Changes in motor movements
• Nausea and vomiting due to increased intracranial pressure
• Unequal pupil size—important to determine if due to neurologic change or
if patient has always had unequal pupil size (small percentage of population
has unequal pupil size)
• Diminished or absent pupil reaction due to neurologic compromise
• Decreased level of consciousness or loss of consciousness
• Amnesia


TREATMENT

• Surgical interventions may be necessary (craniotomy):
• Removal of hematoma
• Ligation of bleeding vessel
• Burr holes (drilling holes) for decompression
• Debridement of foreign material and dead cells
• Administer antibiotics for open head injuries to prevent infection.
• Ventilatory assist if needed—intubation and mechanical ventilation.
• Administer low-dose opioids for restlessness, agitation, and pain in ventilator-
dependent patients:
• morphine sulfate or fentanyl citrate
• Administer osmotic diuretics to reduce cerebral edema:
• mannitol
• Administer loop diuretics to decrease edema and circulating blood volume:
• furosemide
• Administer analgesics:
• acetaminophen (Tylenol)
• High-protein, high-calorie, high-vitamin diet.
• Platelet and packed RBC transfusions—if blood counts warrant transfusion.

NURSING DIAGNOSES
• Risk for injury
• Ineffective tissue perfusion
• Decreased intracranial adaptive capacity
• Risk for disturbed thought processes


NURSING INTERVENTION
• Monitor intake and output.
• Monitor urine specific gravity, serum, and urine osmolarity.
• Collaborate with dietician for appropriate diet, if any swallowing or oral sen-
sory concerns.
• Seizure precautions per institution policy.
• Explain to the patient and family:
• Any dietary restrictions.
• Any activity restrictions.
• Medication actions, side effects, interactions.
• Avoid discussing the patient’s condition in the presence of the patient—
remember the patient can still hear you even though he or she is not con-
scious, and may recall the conversations after they regain consciousness.
• Monitor vital signs for stability—increased blood pressure with widening
pulse pressure and slow pulse, suggestive of increased intracranial pressure.
• Monitor neurologic status for changes—typically use Glasgow Coma Scale
or similar tool to grade response to stimuli (highest score 15):
• Eye-opening response spontaneous 4
to sound 3
to pain 2
none 1
• Motor responses obeys commands 6
localizes pain 5
withdrawal (normal) 4
abnormal flexion 3
extension 2
none 1
• Verbal responses oriented 5
confused conversation 4
inappropriate words 3
incomprehensible sounds 2
none 1

• What to do in case of a seizure, how to protect the patient from further
injury, time the seizure, monitor for breathing, when to call the doctor or
EMS.
• Call your physician at any signs of change in the level of consciousness—
drowsiness, lethargy, change in personality.