Following negative cervical spine imaging in intoxicated patients with no other injuries, some physicians recommend to keep these patients in the ED until the effects of the drugs or alcohol wear off in order to be able to "clinically clear" the spine prior to discharge. The need to retain these patients after ruling out all other injuries contributes to ED overcrowding, increased costs, and increased burden on treating physicians.65 This practice is generally not necessary as CT imaging of the cervical spine is availabl in most facilities and has been shown to be sensitive in the detection of cervical spine injury, including indirect evidence of ligamentous injury. CT is not flawless in detecting injury of course, so when in doubt, obtain an MRI or examine the patient when sober.
The ideal method for clearing the cervical spine in trauma patients who do not have a normal mental status and are in the ICU is controversial. Two opinions predominate: CT is adequate to clear the cervical spine or CT coupled with MRI is necessary to clear the cervical spine in this patient population. The literature contains multiple studies supporting both opinions. For example, Tomycz et al reviewed the records of 690 patients who had both cervical spine MRI and CT after blunt trauma. Of these patients, 180 had a GCS of 13 or greater and had no neurological deficit. All CTs were read as normal. The average time between CT and MRI was 4.6 days. Among these 180 patients, MRI identified 38 patients (21.1%) with acute traumatic findings in the cervical spine. None of these patients had a missed unstable injury and no patient required surgery or developed evidence of delayed instability.128 Conversely, Stassen et al recommended both CT and MRI for obtunded trauma patients, noting that 30% of patients in their prospective study with a negative cervical spine CT had positive findings on MRI for ligamentous injury.129 More research is needed to settle this controversy.
Vertebral and carotid artery dissection can occur with blunt cervical trauma. Blunt cerebrovascular injury is uncommon, with a reported incidence between 1% and 3%; 130-133 37% to 58% of these patients have a permanent neurologic deficit on discharge.130,131,134 The classic presentation of a carotid injury is that of a neurologically intact victim of a motor vehicle collision who subsequently develops hemiparesis.135 Patients included in most studies who are considered to be at risk are those with facial fractures, cervical fractures, low GCS, or signs of vascular or neurologic injury. Mechanisms associated with high risk of blunt carotid and vertebral injury include direct blows to the neck and deceleration injuries producing high shearing forces from a stretching or twisting motion of the neck, such as motor vehicle collisions or falls.101,121,138 Symptoms may be immediate or delayed for days. Almost half of the patients with vascular injury have a normal initial neurologic examination. 136 A retrospective review of the National Trauma Database of >700,000 patients demonstrated that the presence of a cervical fracture produces an odds ratio (OR) for carotid or vertebral artery injury of 8.4 (95% CI, 6.8-10.3), an OR for carotid injury of 2.6 (95% CI, 1.9-3.6), and an OR for vertebral artery injury of 30.6 (95% CI, 21.8-42.8). The presence of a transverse process fracture alone has an OR for vertebral artery injury of 19.5% (95% CI, 12-30.5).137
Cothren et al determined that 3 injury patterns were associated with an increased risk of cervical vascular injury: subluxations, C1 to C3 body fractures, and fractures with extension through the transverse foramen.139 MR angiography has shown promise as an imaging modality for evaluation of vascular injury. It will detect mural hematoma and dissection, pseudoaneurysms, and arteriovenous fistulae. Digital subtraction angiography remains the gold standard to make the diagnosis of cerebrovascular injury. However, multislice CT angiography is often more readily available than angiography but may not be as sensitive. In a prospective study of 216 patients, the combination of CT and MR angiography was directly compared to standard angiography. CT angiography was 47% sensitive for CAI and 53% sensitive for VAI. MR angiography was 50% sensitive for CAI and 47% sensitive for VAI.134 Figure 14 shows a CT of the neck and discusses the findings on the follow-up CT angiogram. CT angiography may lack sensitivity secondary to the associated scatter from bone, especially near the carotid canal, which is an area with high prevalence of injury.135
lists indications for screening for vascular injury.
Pharmacotherapy For Acute Spinal Cord Injury
A number of agents have been studied in an attempt to improve neurologic outcome following spinal cord injury, including naloxone, glucocorticoids, nimodipine, tirilazad mesylate, and GM1 ganglioside. The National Acute Spinal Cord Injury Studies (NASCIS) suggested an outcome benefit of high dose methylprednisolone therapy when given within 8 hours of spinal cord injury.140 The recommendation was the result of a secondary analysis of the data and the overall methodology of the trials have received considerable criticism.141 A randomized trial in France using an identical treatment protocol failed to show a benefit of corticosteroid therapy.142The American Academy of Neurologic Surgeons performed a critical analysis of the trials on steroids in spinal trauma and questioned the benefit of treatment. 143 Currently, steroids in spinal trauma are a treatment option and the negligible potential benefit must be carefully weighed against the potential for harm, ie, increased risk of infection.