Spine trauma and spinal cord injury are a significant problem across the world. In the United States, 12 000 new spinal cord injuries occur per year, and it is estimated that 250 000 individuals are living with this condition. This injury is principally found in men, and the average is 30 years. Cervical spine fractures account for 20% to 30% of all spine fractures with 10% to 20% resulting in spinal cord injury. Approximately 16% of injuries involve the thoracic spine, and the rest include the thoracolumbar junctional segments and the lumbar spine.¹

Management of spinal injury in the intensive care unit (ICU) can improve the patient’s outcome and decrease morbidity and mortality. This chapter (1) provides guidelines for the initial stabilization and workup of patients with spine injuries, (2) presents the concepts of spine stability and the rationale for surgical management, and (3) explains management of ICU-related issues and how to avoid complications.

Initial Resuscitation

Although this patient has clear clinical evidence of a cervical spinal cord injury, the first step in the assessment of any trauma patient begins with the ABCs (airway, breathing, and circulation). Although this evaluation should begin in the emergency department (ED), all critical care specialists should be familiar with the initial resuscitation and should repeat the steps upon arrival to the ICU. Prior to definitive stabilization, the cervical spine should be immobilized in a rigid collar, and the patient should be maintained on a flat, firm surface.^2,3

Airway and circulation are essential in this patient population as hypoxia and hypotension may worsen secondary spinal cord injury,^4,5 and therefore any patient with a clear indication for intubation such as a low Glasgow Coma Scale (GCS) score, hypoxia, or failure of diaphragmatic function should be immediately intubated. The main predictors of intubation in a spine injury include high injury severity scale score, cervical spine injuries above the level of C5, and complete quadriplegia.⁶

Intubation in a patient with a cervical spine injury carries significant risk of worsening the neurologic deficit from excessive neck movement. In-line cervical stabilization with a traditional laryngoscope is an acceptable method, but other methods such as fiberoptic imaging and videolaryngoscopy should be available.^3,7 A surgical airway may also be necessary, and the equipment for this intervention should be immediately available. This patient had an isolated, incomplete spinal cord injury below the C5 level without respiratory compromise, and therefore, intubation was not indicated. However, close monitoring is necessary because delayed respiratory failure is common among spinal cord injury patients.

Simultaneous with the airway evaluation, the patient should be screened for circulatory failure. Neurogenic shock can complicate any injury to the cervical or upper thoracic spine and should be considered in patients with hypotension and bradycardia. This condition is present because of loss of sympathetic tone and inability to maintain an adequate mean arterial pressure (MAP). However, in the setting of trauma, multiple injuries can be present and may complicate the diagnosis. Nearly all forms of shock including cardiogenic, tension pneumothorax, and hemorrhagic shock can be masked by neurogenic shock, and therefore an appropriate resuscitation and workup should be performed.³ Our patient’s workup revealed no evidence of shock other than neurogenic.

The goal MAP in spinal cord injury is > 85 to 90 mm Hg.^4,8 After initial resuscitation, intravenous vasopressor agents should be utilized if this MAP goal cannot be maintained. These medications include dopamine, norepinephrine, epinephrine, and phenylephrine, but no consensus exists on the preferred agent.^2,9,10 Phenylephrine should be used cautiously given the risk of worsening bradycardia. In patients with severe, symptomatic bradycardia, cardiac pacing may be necessary. This patient required dopamine to maintain her MAP > 85 mm Hg.

After determining the ABCs, the patient’s neurologic status including strength, sensation, reflexes, and rectal tone should be assessed. Additionally, a head-to-toe secondary survey is necessary to evaluate for other injuries. Because patient’s motor and sensory system may be compromised by spinal injury, physical examination findings such as abdominal tenderness or guarding may be masked. During the secondary survey, the patient should be maintained in straight alignment and log-rolled and the spine gently palpated for point tenderness and “step-offs,” because 10% of spinal injuries can have an additional fracture at a different level.³

Initial Neurologic Assessment

The initial neurologic evaluation should begin with the GCS assessment. A GCS motor score of 1 (no movement) could reflect a severe traumatic brain injury (TBI) but also may be indicative of a complete spinal cord injury; as many as 5% of patients with TBI have a concomitant spinal injury.³ If the patient is able to cooperate, a complete neurologic examination is essential. The most commonly accepted examination system is from the American Spinal Injury Association (ASIA).¹¹ For the sensory examination, the dermatomes are tested with both light touch and pinprick and given a score of 0 to 2 (0, no sensation; 1, altered sensation; 2, normal sensation). For the myotomes, the score ranges from 0 to 5 (Table 27-1).¹¹

The patient is then assigned a sensory level and muscle level for each side of the body. This neurologic level is the caudal-most level with both full strength and sensation. The impairment scale includes A (complete), B to D (incomplete), and E (normal) (Table 27-1).¹¹ Our patient had a motor level at C5 (with preserved biceps and deltoid function) and no sensory level, and therefore her score is ASIA B at C5.

Because spinal cord and nerve injury may be variable, special consideration should be given to specific conditions. The Brown-Sequard syndrome, which affects half of the spinal cord and causes the ipsilateral motor and light touch dysfunction and loss of contralateral pain sensation, is rarely seen in clinical practice. However, central cord syndrome is a relatively frequent occurrence.

Central cord syndrome is a cervical spinal cord injury, usually in the presence of previous degenerative changes, with preferential weakness in the hands rather than the lower extremities. The central location of the hands within the spinal cord gives this condition its name.¹² However, the exact reason for the preferential weakness in the hands remains controversial, and many theories include central necrosis with hematomyelia or the over-representation of the hands within the corticospinal tracts. Although early decompression in the presence of fracture-dislocations is recommended, the timing of surgery for patients with degenerative spinal stenosis without fracture is controversial.¹³ Our practice is to decompress the injury as soon as the patient is medically stable.

Cauda equina and conus medullaris syndromes are also important entities. Compression of this area will result in bilateral lower extremity weakness with lower motor neuron signs (and some upper motor neurons when the conus is involved) with sensory loss in the saddle area or perianal area. Bowel and bladder incontinence are fairly common, especially when the conus is affected. In the traumatic setting, these conditions are surgical emergencies and require emergent decompressions.¹¹

After medical stabilization and a neurologic exam, imaging is indicated.

The choice of imaging in the trauma patient is dependent on the availabilities at the particular institution and the clinical suspicion of injury. In our patient, the high-energy mechanism of injury and obvious neurologic deficit necessitates multilevel imaging. The first imaging should include plain films of the chest because significant pulmonary contusions or hemopneumothorax should be treated prior to any further imaging.

Any patient who is altered or has a neurologic deficit, such as our patient, should receive computed tomography (CT) scans of the brain, cervical spine, and chest/abdomen/pelvis. Individualized CT scans of the thoracic, lumbar, and sacral spines are unnecessary if a CT scan of the chest/abdomen/pelvis is obtained because the imaging detail is generally adequate for surgical planning.¹⁴ We do not perform plain radiographs of the spine in patients with obvious pain, neurologic deficit, or suspicious mechanism of injury as these studies are superfluous in the presence of a CT scan. Spinal imaging in patients with no midline tenderness, a normal level of alertness, no distracting injuries, no neurologic deficits, and no evidence of intoxication is not needed by the NEXUS (National Emergency X-ray Utilization Study) criteria.¹⁵ The CT scan of the patient’s cervical spine is shown in Figure 27-1.

The use of magnetic resonance imaging (MRI) in acute spine trauma is controversial, case dependent, and institutional dependent. The principle benefit of MRI is to evaluate for soft tissue lesions such as traumatic spinal hematomas, ligamentous disruption, or herniated disc fragments.² In stable fractures without neurologic compromise such as transverse process fractures and spinous process fractures, MRI is not indicated. As a general guideline, if a spinal hematoma or traumatic disc herniation is suspected based on CT or neurologic deficit, an MRI is needed. Additionally, if the stability of the fracture is unclear based on the CT scan, then MRI may provide added detail. However, MRI may be too sensitive in certain cases and can confuse soft tissue edema and ligamentous injury.¹⁶

For our patient, an MRI of the cervical spine may determine if a traumatic, herniated disc is present. If this lesion is detected, the application of traction with fracture reduction may result in further disc herniation and additional spinal cord injury. If a traumatic disc is found, a ventral decompression prior to reduction should be performed. However, the true risk is unclear and this decompression remains controversial. Also if an MRI is difficult to obtain in a timely fashion, relief of spinal cord compression may outweigh the risk of further disc herniation.² As a general guideline, if the patient is neurologically intact, an MRI prior to application of traction would ensure the safest possible reduction. If a patient has a complete spinal cord injury, immediate reduction without further imaging would give the best chance for neurologic recovery. For incomplete patients with incomplete injury, such as our patient, if an emergent MRI is possible, then MRI prior to reduction is our preferred workup.

Cervical spine clearance in the comatose patient remains a controversial topic. Several options exist including clearance based on lack of acute findings on CT, cervical spine MRI, flexion extension radiographs, or continuing the collar for a specified period of time. In a large meta-analysis by Panczykowski et al, more than 14 000 patients were studied, and only 7 patients were found to have cervical spine injuries without CT evidence of instability.¹⁷ Our approach utilizes these data as well as clinical judgment.

Upon arrival at the hospital, all patients are placed in a cervical collar, and a CT scan is obtained. If the CT does not show acute findings or severe degenerative disease, and the patient does not have a neurologic deficit that is unexplained by the current imaging, the collar is removed. If the patient has severe degenerative disease and is at risk for a spinal cord contusion without spine fracture or has a neurologic deficit such as paraplegia that may localize to the spinal cord or nerves, then an MRI of the cervical spine is obtained prior to removal of the collar. If the patient is expected to regain consciousness in the near future, as would be expected with minor cranial injuries with alcohol or drug intoxication, the cervical collar remains in place for a few days to see if it may be clinically cleared as well.

The administration of neuroprotectants such as methylprednisolone has been a controversial topic in spinal cord injury. Four randomized, blinded trials have failed to show benefit with steroids, and multiple retrospective reviews had mixed results. Post-hoc analyses of the National Acute Spinal Cord Injury Study (NASCIS) II and III demonstrated improvement in both motor and sensory with persistent motor benefits at 1 year if steroids were administered within 8 hours of injury, but neither study was designed to test this finding.^18,19

The adverse effects of steroids in this population are significant. Infections including wound infections, pneumonia, urinary tract infections, and sepsis are increased with steroids. Additionally, hyperglycemia is relatively common, and gastrointestinal hemorrhage may occur. Finally, in the polytrauma patient, many conditions such as TBI have been associated with a worse outcome with steroids.²⁰ For this reason, the American Association of Neurologic Surgeons does not recommend the routine use of steroids in spinal cord injury.² Our patient did not receive steroids for the entirety of her hospitalization.

The determination of fracture stability is paramount for the immediate and long-term care of the patient. Stability is determined by a multitude of factors including the biomechanical properties of the spine after injury, the presence or absence of neurologic injury, and the changes over time that will occur with normal physiologic loading. In general, a fracture is considered unstable if normal physiologic loading will result in neurologic or structural decline or deficit including significant pain.²¹ Many different classification systems exist, but the multitude of fracture types makes any comprehensive system difficult.

The spine may be divided into dorsal and ventral elements. The ventral vertebral bodies and intravertebral discs are the primary load-bearing elements. The discs also absorb shock and allow for spinal movements. The dorsal elements, including the spinous processes, lamina, transverse processes, and facet joints allow for neural elements protection, for muscles attachment, and for the mobility limitations of the spine itself. The pedicles connect the ventral and dorsal elements and are a key structure for instrumented stabilization.²²