Central nervous system injury can be divided into two major categories, head injury
(HI) and spine/ spinal cord injury (S/SCI). Steps taken by medical personnel in the first
hours after injury are critical in maximizing neurologic recovery.
Head Injury (HI)
HI and its variations can best be categorized, diagnosed, and treated by
first considering the layers and tissue types which protect the brain. The scalp consists
of five layers and these can be remembered by the phrase SCALP:
Sub Cutaneous tissue
Loose connective tissue
Pericranium (the periosteum of the skull)
The galea is the layer that provides the greatest strength to the scalp. When the
galea is cut, the scalp readily slides apart because of the underlying loose connective
tissue. In a scalp wound, the appearance of a gap between the edges of a laceration
signifies that the galea has been interrupted; similarly, avulsed or partially avulsed
scalp flaps also signify galeal disruption. Some scalp lacerations are impressive, with
large areas of avulsion/flap; in children especially, such lacerations may be a source of
shock-producing, life-threatening hemorrhage.
Scalp wound evaluation
Once a scalp laceration is identified, ascertain whether deeper layers
have been affected (skull, brain). Observation and palpation easily accomplish the
evaluation. A depression in the skull may be palpated, as may bone fragments. The
appearance of clear fluid indicates spinal fluid leakage, which further (logically) means
dural interruption. Brain tissue will look like thick plain yogurt - its appearance in the
wound also means dural laceration.
In traumatic vascular injuries to other parts of the body,
hemostats/clamps are not to be applied, since further injuries may be produced; in these
other regions, direct pressure is the recommended technique. With scalp lacerations,
however, bleeding vessels may be clamped. If the vessel cannot be clearly identified or if
the hemostat is not handy, and the skull underneath is intact, pressure with one or more
fingertips may be applied to compress the vessel between the finger and the skull.
Obviously, direct pressure must not be applied to any regions of skull depression or brain
tissue. Hemostats must not be applied to cerebral tissue.
Scalp lacerations may be associated with severe underlying brain
injuries. A patient with a severe injury or developing neurologic deficit must be rapidly
evaluated for treatment and transfer. Except in unusual circumstances, burr holes (holes
in the skull drilled to release blood clots) are not performed by GMOs, at least not
without special training or concurrence in specified cases or situations.
breathing, and circulation (ABCs)
Most GMOs have taken the Advanced Trauma Life Support (ATLS) course. While the
amount of information presented in ATLS may appear overwhelming, the basic principle of
first assessing the ABCs should be thoroughly understood and practiced by anyone dealing
with a trauma patient. Do not give into the temptation of palpating a scalp wound or
looking at the pupils until the patient has a secure airway, is breathing adequately, and
has a stabilized circulatory status. Nothing is more important than the ABCs. After the
ABCs, D (disability) and E (exposure) have been attended to, the secondary survey can be
performed to include a more detailed examination of the patient's neurologic status.
The hallmark of brain injury: alteration of
Evaluate what the patient responds to and what level of stimulation is
necessary to produce a given response. The
Glasgow Coma Scale (GCS) is used to grade the severity of injury. See the below table.
The numbers are not as important as understanding the basic principles and being able to
describe to someone what the patient can or cannot do at a given moment. Neurologic
improvement or deterioration must be assessed early and frequently. Using the GCS,
evaluate the patient according to the degree of stimulation required to produce a given
response. Responses to stimuli allow the physician to determine the patients basic
mental status. The initial exam will serve as a baseline with serial exams providing
information that can indicate the stability of the clinical status and the effectiveness
of treatments. Corpsmen, nurses, and doctors may have trouble remembering the GCS, but if
you understand the idea behind it, you can still examine the patient and convey the
Glasgow Coma Scale
oriented and converses
to voice command
localizes to pain
to pain stimuli
withdrawals from pain
V + M = 3 to 15
Recommended for age > 4 years
The GCS is intended to assess level of consciousness, not follow focal
Major Areas to Focus on with Patients that
Sustain a Head Injury:
Disability (D). The goal of assessing disability is to determine neurologic injury.
Key components of this evaluation are as follows:
Mental status (GCS).
Motor/sensory exam of the extremities.
Decline in neurologic status. This will be noted by performing serial
exams. It is fairly obvious that a patient who comes in talking and then stops talking and
is decerebrate to painful stimulus has deteriorated. However, what are some earlier signs?
Decrement in level of consciousness. A patient who was previously talking
to you but now has to be shaken gently or have a painful stimulus applied before he or she
talks to you, or other decline along the lines of the GCS.
A pupil which becomes less responsive to light and larger than the opposite one.
Pupils are best examined in a darkened room; otherwise the ambient light causes
stimulation and rest/response sizes are misgauged.
When neurologic decline occurs, additional treatment modalities need to be considered
and transfer must be implemented.
Remember, the ABCs must be maintained. In addition, there are some specific therapeutic
interventions that can be implemented by the GMO to improve the head injury patient's
chances of recovery. These efforts are directed at lowering the intracranial pressure.
Elevate the head of the bed
Blood pressure stability/lability and the presence of shock will determine the extent at
which this maneuver is performed. Be careful if the patient is secured on a long spine
board and if a potential spinal injury exists.
Traditional belief has mandated hyperventilation as a standard treatment for elevated
intracranial pressure management. Hyperventilation lowers the pC02, which, in turn,
decreases cerebral blood flow (CBF) and some of the intracranial mass contributed by the
blood in the cerebral vessels. Unfortunately, the baseline CBF following head injury can
be as low as 50 percent of normal. Recent studies have demonstrated that hyperventilation
in the face of decreased CBF states results in ischemic injury to the brain. Thus, the
current recommendation is to avoid hyperventilation except in an acute herniation
syndrome. The optimum pC02 is 31-35 mm; below this, there is too much of a decrease in
cerebral blood flow, and brain metabolism is compromised.
Keeping in mind that the "C" of the ABCs must be supported. Patients with HI
should receive fluids necessary to perfuse all organs, including the brain. Again,
"C" is always supported without regard to head injury, since inadequate cerebral
perfusion is bad for the patient with HI. Avoid the use of hypotonic fluids. Maintain
serum osmolality between 285-300
These agents (urea or mannitol/lasix) may be administered in the event of neurologic
deterioration only on the advice of a neurosurgeon. If the patient has required volume
loading to treat shock, these agents will most likely cause shock again, and would
therefore not be advised.
Other Treatment Options
Barbiturates are sometimes used for cerebral protection in severe head injury. However,
their use requires careful monitoring of intracranial pressure since these medications can
negate neurologic exam results. Remember that assessing for changes in the neurologic exam
can provide the best way of determining if the patient needs to be treated and/or
Vital information for the neurosurgeon
Status of the ABCs.
The patient's level of consciousness (GCS or equivalent in plain language).
Has he or she changed under your care?
Scalp/head injuries that can be visualized.
Results of any x-rays/labs and other injuries.
Mechanism of injury, if known.
Spine/Spinal Cord Injury
Early evaluation and treatment of the patient with spine/spinal cord injury (S/SCI) is
not difficult, as long as some basic principles are remembered and followed.
Always suspect the presence of these types of injuries. Patients with head injuries
and/or unconsciousness, supraclavicular injuries, or those involved in high-speed
vehicular accidents are all suspect, as is the patient in whom there is an obvious
neurologic deficit which can be traced to the spinal cord.
The second principle is immobilization.
All patients who are suspected of having S/SCI should be completely immobilized on a
spine board with collar and sandbags. The ATLS course and skill stations provide a basis
for the techniques and equipment used in immobilization; common sense, and ingenuity may
be needed in situations where standard equipment is unavailable.
Concurrent with the suspicion and immobilization phases is the assessment of the ABCs.
The airway and breathing of the S/SCI patient may be compromised by:
Local neck trauma or
Impairment of diaphragmatic/accessory muscle function.
These patients may appear to have satisfactory respiratory function upon initial
evaluation, but they frequently tire; this is best prevented by early intubation with
(attention to immobilization), rather than waiting until the patient gets into serious
trouble during transfer.
The next factor to assess is "C." A spinal cord injury, especially one
that achieves complete physiologic or
physical transection of the spinal cord, causes a sympathectomy. This is manifested by
hypotension and bradycardia. The concurrence of SCI with hypotension and bradycardia is
known as neurogenic shock; it is crucial to the survival of the patient to diagnose and
treat any concomitant hypovolemic shock, since the SCI patient is unable to mount the
characteristic tachycardia of hypovolemic shock. The SCI patient's neurologic dysfunction
interferes with evaluation of the abdomen, pelvis, and legs, all places where significant
causes of hypovolemic shock may lurk. Since the sympathectomy effect has essentially
increased the volume of the intravascular tank, volume expansion may not have much of an
effect on the blood pressure (BP). A BP of 90 mmHg, however, is adequate for perfusion in
the supine position (which this patient will be in since he or she is properly
immobilized). A foley catheter should be inserted to prevent bladder distention and assess
renal function as an indicator of perfusion.
Neurologic assessment of the patient is necessary to determine his or her initial
status and to document
any improvement or decrement in function. While a formal neurologic exam is required,
impressions of the patient's neurologic function can be gained from his or her conduct
during the initial phases of evaluation and resuscitation; how does he or she respond to
the painful stimuli of IVs and blood drawing? Does the patients arms and legs move
in response to stimuli? Flaccidity of muscles and absence of reflexes are the rule in the
early hours and days following spinal cord injury; this symptom complex is known as spinal
shock, and it usually is replaced by the classic spasticity and hyperactive reflexes of
upper motor neuron lesions in several days to weeks following the injury. A critical
determination is the presence or absence of sacral sensation; its presence denotes an
incomplete spinal cord injury (some messages are getting past the injury), and signals a
much more hopeful prognosis for return of neurologic function than for the patient in whom
it is absent.
The primary job of the persons caring for a patient with a (potential) S/SCI is to
prevent worsening of the neurologic status. This includes proper immobilization and
continuous re-evaluation of the neurologic status. Definitive treatment is performed at a
center with neurosurgical or orthopedic spine expertise.
Controlled studies have demonstrated improved neurologic outcome in patients with
spinal cord injury who receive steroids early after the injury. Steroid administration is
indicated for non-penetrating spinal cord injury, but it must be given within 8 hours of
the injury. The dosing of methylprednisolone is 30 mg/kg IV bolus over 15 minutes.
Forty-five minutes after bolus completion, start methylprednisolone infusion at 5.4
mg/kg/hr for 23 hours.
Transfer planning and recommendations
Vital information for the accepting physician includes the patient's neurologic
status and course while under observation, the status of the ABCs, and any associated
injuries. Careful transfer of the patient must be carried out, and pretransfer thought
given to any untoward events which might be anticipated by the patient's status.
Pretransfer intubation may need to be considered, depending upon severity of injury,
distance, mode of transfer, and sophistication of personnel accompanying the patient.
Prevention is the best treatment for spinal cord injuries. The GMO can help prevent
spinal cord injuries by encouraging each patient to use seat belts, drive a car with an
airbag, and avoid driving while intoxicated. Also encourage patients to avoid traveling as
a passenger with an intoxicated driver. Diving represents another mechanism of injury,
particularly in locations where depth/obstacles may be unknown. The neurosurgical
community has encouraged the feet first, first time campaign to try to minimize the
occurrence of diving-related SCI. Prevention works best.
Reviewed and revised by CDR Robert Heim, MC, USN, Neurosurgery Specialty Leader
and Staff Neurosurgeon, National Naval Medical Center, Bethesda, MD. (1999).