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1150 PART 10: The Surgical Patient

or acute fracture-dislocations. This syndrome is characterized by dispro- There is now growing evidence to support cervical spine clearance
portionate weakness in the upper versus the lower extremities, most pro- in many unreliable patients on the basis of high-resolution CT alone.
found in the hands and forearms, and is often sacral-sparing, although In the vast majority of papers reporting “missed” C-spine injuries with
bladder, bowel, and sexual dysfunction can be seen in severe cases. CT imaging, retrospective review of these CT images revealed that these
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These patients may present with initially complete or near-complete injuries were, in fact, detectable on the original CT. Careful review of cer-
quadriplegia, often due to a spinal cord concussion (a reversible condi- vical spine CT images in the axial, coronal, and sagittal planes, including
tion similar to its cranial counterpart) with rapidly noted improvements all bone and soft tissue windows, approaches 100% sensitivity. 61,63,64 The
in motor function over the first 24 hours of injury. The severity of injury current literature indicates that MRI does not likely provide additional
can vary and can also be asymmetrical. Central cord syndrome patients clinical benefit in patients with truly negative CT imaging. Therefore, for
can continue to improve over several weeks to months without surgery, unreliable patients with no neurological deficit otherwise explained by a
though many experience a plateau in neurological recovery or may coexisting head injury, it is our current practice to remove cervical collars
experience delayed deterioration, possibly due to continued compression based upon carefully reviewed negative CT imaging. This review should
from their existing disease. 58,59 Treatment options include acute medical be conducted by an experienced radiologist and/or a spine surgery
management of the SCI with later rehabilitation and/or surgical decom- consultant. Trauma and critical care providers might also choose to
pression. Literature has shown that functional recovery is accelerated obtain a spine surgery consultation before considering collar removal
with surgical decompression, indicating superiority of surgery to conser- to verify clinical and radiographic findings. 65
vative management alone. There is controversy as to the timing of such
surgery, which usually entails either posterior or anterior decompression
and fusion, or both. Surgery can be performed early (within 24 hours) or NEUROPROTECTION
in a delayed fashion (>24 hours to >2 weeks). Delayed surgery allows The prevention of secondary injury or “neuroprotection” consists of
for reduction of spinal cord edema and natural improvements in spinal spine immobilization, timely surgical intervention, and early recogni-
cord function. In a recent literature review, central cord injury patients tion and treatment of hemodynamic instability, respiratory failure,
with ASIA C scores appeared to have greater functional improvement and hypoxemia. Potential pharmacotherapeutic neuroprotective agents
with early surgery, with patients with less severe examinations potentially studied thus far include steroids, opiate blockers (Naloxone), GM-1
benefitting from delayed decompression. 59 ganglioside (Sygen), thyrotropin-releasing hormone (TRH), erythropoi-
etin (EPO), aspartate receptor antagonists (gacyclidine), and free radical
scavengers (tirilazad). At this time there is no conclusive evidence that
CERVICAL SPINE CLEARANCE high-dose intravenous steroids or any other proposed neuroprotective
It is recommended to remove a spinal immobilization board as soon as agent improves functional recovery after spinal cord injury (SCI). 66-69
possible in the emergency department to avoid decubitus ulcers, espe- Ongoing and future investigations will consider nerve-growth factors,
cially in paralyzed patients. Collars need to be kept in place in patients induced pluripotent stem cells, olfactory ensheathing glia, mesenchymal
who are not able to reliably report neck pain. These patients include any stromal cells, and activated autologous macrophages. 7,70,71
person with impaired consciousness or with a significant distracting Methylprednisolone, the most widely used agent in acute SCI, became
injury. A distracting injury is defined as any injury (eg, extremity, espe- the standard of care for the treatment of acute SCI in the early 1990s
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cially proximal to the spine) causing significant enough pain to mask subsequent to the NASCIS (National Acute Spinal Cord Injury Study) I
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or reduce pain perception from another site. However, in such patients, and II. 73,74 The NASCIS II and later NASCIS III trials reported benefit
prolonged hard cervical collars usage can be associated with significant in neurological outcome at 6 weeks, 6 months, and 1 year in patients
complications such as decubitus ulcers, less effective nursing care, pneu- with both complete and incomplete injuries.
monia, and more difficult respiratory support. If the patient is expected However, more recent reviews have been very critical of the statistical
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to regain full consciousness within 24 to 48 hours, full spinal precautions analysis and interpretation of these trials. 66,76,77 A critical analysis of nine
are continued until the patient is fully conscious and can cooperate studies (including the NASCIS trials) evaluating the role of steroids in
with clinical exam. In the absence of radiographic abnormalities, such nonpenetrating spinal cord injury, five class I clinical trials, and four
patients with good cervical range of motion and no significant neck pain class II studies, pointed out the lack of benefit of steroid administration
do not require cervical collars. The conundrum lies in the clearance of in any a priori hypotheses testing. Only in post hoc defined subgroups
cervical spines in unreliable patients because premature collar removal were statistically significant or interesting benefits found, but no con-
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in an unstable spine can result in devastating neurological deficits. sistent significant treatment effects were demonstrated. Acute steroid
Plain radiographs, as previously mentioned, are not sufficient to administration is associated with increased complication rates of hyper-
detect all fractures. MDCT scans with reconstructed images in the axial, glycemia, infection, and sepsis.
coronal, and sagittal planes are far superior in detecting fractures and Despite published data and the known risk of potential complications,
can also demonstrate soft tissue injuries such as prevertebral swelling some spine surgeons continue to employ intravenous steroids after acute
and some disc herniations, especially at the superior levels of the cervi- SCI using the NASCIS III protocol. The recommended regimen is a
cal spine (the shoulders tend to create streak artifacts through the lower loading dose of 30 mg/kg intravenous methylprednisolone over 1 hour,
cervical spinal canal obscuring disc visualization). CT, however, cannot followed by a continuous infusion of 5.4 mg/kg per hour over 23 hours
exclude ligamentous instability. Dynamic flexion/extension fluoroscopic started within 3 hours of the acute SCI or continued for 48 hours if it is
imaging has been suggested in the past for clearance of unreliable started within 3 to 8 hours of the acute SCI. In neurologically normal
patients, but passive movement of a potentially unstable cervical spine patients, and those in whom neurological symptoms have resolved,
can place the patient at high risk for neurological compromise. MRI, steroids may be discontinued to reduce deleterious side effects. 5
being superior to CT for identifying ligamentous, disc, or other soft
tissue injuries, may show such injuries in approximately 25% of patients TEMPERATURE REGULATION AND HYPOTHERMIA
with negative CT imaging. However, there is a well-known false
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positive rate for clinically significant MRI findings as not all ligamentous Temperature should be monitored and regulated, avoiding extreme
injuries, especially those involving only one spinal column, indicate a hypothermia.
need for spinal stabilization. There are also significant risks in taking Hypothermia and hyperthermia may be encountered due to auto-
severely injured, mechanically ventilated patients to the MRI suite, such nomic dysregulation. Systemic hypothermia in the treatment of severe
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as ICP elevations, hemodynamic instability, or respiratory complica- cervical spinal cord injury is being evaluated in an early phase I clinical
tions, all with the potential for further secondary brain injury. 62 trial and appears to be safe; however, continued trials will be needed to

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