General
- Major causes of death in spinal cord injury (SCI) are
- Aspiration
- Shock.
- Trauma patients are triaged as follows
- No history of significant trauma, completely alert, oriented, and free of drug or alcohol intoxication, with no complaints referable to the spine
- Most may be cleared clinically without the need for C-spine X-rays
- Significant trauma, but no strong evidence of spine or spinal cord injury
- The emphasis here is in ruling out a bony lesion and preventing injury
- Patients with neurologic deficit
- Aim
- Define the skeletal injury
- Prevent further cord injury and loss of function
- Minimize or reverse the present deficit.
- The pros and cons of the high-dose methylprednisolone protocol should be weighed if a neurologic deficit is identified
Management in the field (ATLS guidelines)
- General
- Any of the following patients should be treated as having an SCI until proven otherwise
- All victims of significant trauma
- Trauma patients with loss of consciousness
- Minor trauma victims with complaints referable to the
- Spine (neck or back pain or tenderness)
- Spinal cord (numbness or tingling in an extremity, weakness, paralysis)
- Associated findings suggestive of SCI include
- Abdominal breathing
- Priapism (autonomic dysfunction)
- Some 25% of prehospital fatalities are aggravated after the initial event
- ABC → brief neurologic exam.
- NB: other injuries (e.g. abdominal injuries) may be masked below the level of SCI.
- Spine immobilization prior to and during extrication from vehicle and transport
- Aim
- To prevent active or passive movements of the spine.
- The Kendrick extrication device,
- 3 point spinal stabilization
- Sandbags on both sides of the head
- 3 inch strip of adhesive tape from one side of the back-board to the other across the forehead
- Rigid cervical collar
- Allows movement of the jaw and access to the airway
- Cervical spine immobilization must be maintained by stabilizing both the torso and the head during transfer to the nearest trauma centre
- Maintain oxygenation (adequate FIO2 and adequate ventilation)
- If no indication for intubation: use NC or face mask
- Intubation
- May be required for airway compromise or for hypopnea.
- In SCI, hypopnea may be due to
- Paralyzed intercostal muscles,
- Paralysis of diaphragm (phrenic nerve = C3, 4 & 5).
- LOC in TBI caution with intubation with uncleared C-spine
- Use chin lift (not jaw thrust) without neck extension
- Nasotracheal intubation may avoid movement of C-spine but patient must have spontaneous respirations
- Avoided tracheostomy or cricothyroidotomy if possible (may compromise later anterior cervical spine surgical approaches)
- Maintain blood pressure, see below under Hypotension
- Systolic blood pressure
- Give vasopressors to keep MAP above 90 mmHg ACS
- Pressors treat the underlying problem
- As SCI is essentially a traumatic sympathectomy
- Dopamine is the agent of choice, and is preferred over fluids (except as necessary to replace losses)
- Avoid phenylephrine (see below)
- Fluids as necessary to replace losses
- Military anti-shock trousers (MAST): immobilizes lower spine, compensates for lost muscle tone in cord injuries (prevents venous pooling)
- Brief motor exam to identify possible deficits (also to document delayed deterioration); ask patient to
- Move arms
- Move hands
- Move legs
- Move toes
Management in the hospital
- Hospital phase and secondary survey
- A rigid spinal board should be removed soon after the patient arrives in the emergency department to prevent pressure ulcers.
- Respiratory status must be monitored, since one- third of patients will require intubation in the first 24 hours.
- High cervical injuries paralyse the diaphragm and intercostal muscles,
- Paradoxical abdominal movement with respirations is often observed in patients with spinal cord injury above C5.
- Lower cervical injuries affect the intercostal muscles only.
- Intubation is recommended in patient with vital capacity < 1L
- During the secondary survey, an entire evaluation of the spine is required since many injuries may not be obvious while the patient is kept in the supine position.
- Immobilization
- Backboard/head-strap
- Keep on to facilitate transfers to CT table, etc. Log-roll patient to turn.
- Once studies are completed, remove patient from backboard ASAP
- Early removal from board reduces risk of pressure sores
- Cervical collars
- Should be removed as soon as it can be determined that it is safe to do so. Because
- Reduce skin breakdown
- Fewer days of mechanical ventilation
- Shorter ICU stays
- Reduction of ICP
- Guidelines for “clearing“ the cervical spine
- A cervical collar is not needed in trauma patients who meet these criteria
- Asymptomatic patients: radiographic evaluation in asymptomatic trauma patients: those who are alert, without neurologic deficit or distracting injury who have no neck pain or tenderness and full range of motion (ROM) of the cervical spine.
- Penetrating brain trauma: unless the trajectory suggests direct cervical spine injury.
- Level II & level III: patients who are awake with neck pain/tenderness and normal cervical CT scan after either (these testes are performed in the absence of an identifiable # or obviously unstable dislocation to rule out ligamentous or other soft-tissue injury that might be occult and unstable)
- Normal and adequate dynamic flexion-extension C-spine X-rays.
- Or a normal cervical MRI is obtained. Note: AANS/CNS guidelines from 2002 recommended obtaining the MRI within 48 hours. MRI is usually employed in this setting when the patient cannot cooperate for flexion-extension X-rays); see MRI findings and issues related to timing.
- In obtunded patients with normal cervical CT scan and gross movement of all four extremities
- ❌ Flexion-extension C-spine X-rays should not be performed (Level II).
- Options
- Maintain cervical collar until a clinical exam can be performed.
- Remove the collar on the basis of the normal CT scan alone (the incidence of ligamentous injury with negative CT is <5%, and the incidence of clinically significant injury is unknown but is much < 1%).
- Obtain cervical MRI (AANS/CNS guidelines from 2002 recommended getting the MRI within 48 hours)
- Level III: the risk and benefit of cervical MRI in addition to CT is unclear, and must be individualized.
- Level II: if the MRI is normal, the collar may be safely removed.
- ASIA assessment
- Imaging
- The unconscious or uncooperative patient in the trauma setting should be assumed to have a spinal injury until proven otherwise.
- CT
- Can identify 99.3% of all fractures of the cervical, thoracic, and lumbar spine
- Those injuries missed by helical CT required minimal or no treatment
- MRI
- Indicated
- CT results do not explain the neurological status
- Seen in the neurologically impaired victim with an unremarkable CT.
- To exclude the presence of an associated extruded disc before or after a reduction manoeuvre in patients with cervical facet subluxations or dislocations.
- Cervical traction
- Halo application has been advocated in polytrauma patients given, its ability to facilitate further necessary diagnostic evaluations and emergent surgical treatment of associated injuries in the polytrauma patient.
- The benefit of closed cervical reduction and traction is controversial.
- Cervical traction can be used with a reported 80% success rate and 80% rate of improved neurological function
- Worsening neurologic status from disc herniation after cervical traction may also occur.
- It is emphasized that such a strategy is not universally employed.
- Hypotension (Neurogenic shock)
- NG tube to suction
- Prevents vomiting and aspiration, and decompresses abdomen which can interfere with respirations if distended (paralytic ileus is common, and usually lasts several days)
- Indwelling (Foley) urinary catheter
- To monitor In and output
- To prevent distension from urinary retention
- DVT prophylaxis
- Sanjay 2013
- Numbers
- Incidence of DVT may be as high as 100% when 125I-fibrinogen is used.
- 40% develop in 1st two weeks
- Overall mortality from DVT is 9% in SCI patients.
- Prophylaxis
- A study of 75 patients found titrating dose of SQ heparin q 12 hrs to a PTT of 1.5 times control resulted in lower incidence of thromboembolic events (DVT, PE) than “mini-dose” heparin (5000U SQ q 12 hrs) (7% vs. 31%).
- Heparin can cause thrombosis, thrombocytopenia and chronic therapy may produce osteoporosis
- Level I
- Prophylactic treatment of venous thromboembolism (VTE) in patients with severe motor deficits resulting from SCI. Choices include
- LMW heparin, rotating beds, adjusted dose heparin, or some combination of these measures.
- Or, low-dose heparin + pneumatic compression stockings or electrical stimulation.
- Level II
- Early administration of VTE prophylaxis (within 72 hours).
- Treat for 3 months.
- Low-dose heparin should not be used as a standalone treatment.
- Oral anticoagulation should not be used as a standalone treatment.
- Level III
- Vena cava interruption filters are not recommended for routine prophylaxis; they may be used for select patients who fail anticoagulation or are not candidates for anticoagulation.
- Diagnosis
- Level III
- Duplex Doppler ultrasound
- Impedance plethysmography
- Venography
- Clinical examination
- Low molecular- weight heparin,
- Rotating beds,
- Adjusted dose heparin,
- Pneumatic compression stockings
- Oral anticoagulation alone does not appear to be as effective as these other measures used for prophylaxis.
- When to start
- Start mechanical and chemical prophylaxis upon admission after SCI
- Start chemical prophylaxis
- 1 day prior AND
- 1 day following surgical intervention.
- When to stop
- 12 weeks following spinal cord injury.
- Class II medical evidence indicates that the majority of thromboembolic events occur in the first 3 months following acute SCI and very few occur thereafter.
- The incidence of thromboembolic events appears to decrease over time
- Unless the patient is at high risk for a future VTE event (previous thromboembolic events, obesity, advanced age).
- The prolonged use of anticoagulant therapy is associated with a definite incidence of bleeding complications.
- It is reasonable to discontinue therapy earlier in patients with retained lower extremity motor function after spinal cord injury, as the incidence of thromboembolic events in these patients is substantially lower than among those patients with motor complete injuries.
- IVC (Caval) filters
- Indication
- SCI patients who have suffered thromboembolic events despite anticoagulation
- Before using IVC filters try and look for cause of repeated thromboembolic events
- Poor adherence to clexane etc
- SCI patients with contraindications to anticoagulation and/or the use of pneumatic compression devices.
- Complications
- Post-thrombotic syndrome(PTS)
- Oedema was 42.9 %
- Chronic skin changes (including venous ulcers) was 12 %.
- IVCF misplacement
- Pneumothorax,
- Local hematoma,
- Air embolism,
- Carotid artery puncture
- Arteriovenous (AV) fistula formation.
- Temperature regulation
- Vasomotor paralysis may produce poikilothermy (loss of temperature control), this should be treated as needed with cooling blankets
- Electrolytes
- Hypovolemia and hypotension cause increased plasma aldosterone which may lead to hypokalemia
- More detailed neuro evaluation
- Patients may be stratified using the ASIA impairment scale
- Focused history
- Mechanism of injury (hyperflexion, extension, axial loading…)
- History suggestive of loss of consciousness
- History of weakness in the arms or legs following the trauma
- Occurrence of numbness or tingling at any time following the injury
- Examination
- Palpation of the spine for point tenderness, a “step-off,” or widened interspinous space
- Motor level assessment
- Skeletal muscle exam (can localize dermatome)
- Rectal exam for voluntary anal sphincter contraction
- Sensory level assessment
- Sensation to pinprick
- Tests spinothalamic tract, can localize dermatome
- Be sure to test sensation in face also
- Spinal trigeminal tract can sometimes descend as low as ≈ C4
- Light (crude) touch
- Tests anterior cord (anterior spinothalamic tract)
- Proprioception/joint position sense
- (Tests posterior columns)
- Evaluation of reflexes
- Muscle stretch reflexes
- Usually absent initially in cord injury
- Abdominal cutaneous reflexes
- Cremasteric reflex
- Sacral
- Bulbocavernosus
- Anal-cutaneous reflex
- Examine for signs of autonomic dysfunction
- Altered patterns of perspiration (abdominal skin may have low coefficient of friction above lesion, and may seem rough below due to lack of perspiration)
- Bowel or bladder incontinence
- Priapism: persistent penile erection
Medical management specific to spinal cord injury that should not be done
- Methylprednisolone (MP)
- MP is not FDA approved for use in treating acute SCI.
- There is no Class I or II evidence of benefit supporting this use of MP.
- Class III data had been used to advocate its use, but the benefits were likely due to random chance and/or selection bias.
- Class I, II and III level evidence shows that high dose steroids are associated with harmful side effects and even death.
- Use of high-dose MP among spine surgeons has shown a steady decline;
- However, it was still used by as many as 56% of respondents to one survey.
- Methylprednisolone sodium succinate (MPSS) was extensively studied in five human SCI trials.
- Three multicenter, randomized, double- blinded National Acute Spinal Cord Injury Studies (NASCIS) → do not use
- What is the proposed mechanism of action of steroid treatment in blunt spinal cord injury?
- Have effects on local blood flow, inhibition of immunologic injury, and free radical-mediated lipid peroxidation and neuronal damage.
- Experimental/investigational drugs
- None of these agents shown to have unequivocal benefit in man
- Naloxone,
- DMSO, Lazaroid®
- Tirilazad mesylate (Freedox®) was less beneficial than methylprednisolone
- Hypothermia for spinal cord injury
- The position statement of the joint sections of the AANS and the CNS is that there is not enough evidence to recommend for or against local or systemic hypothermia for acute SCI,
- Systemic hypothermia is associated with medical complications in TBI.
Timing of surgery following spinal cord injury
- Cautions and contraindications
- ❌ Caution: laminectomy in the face of acute spinal cord injury has been associated with neurologic deterioration in some cases.
- When emergency decompression is indicated, it is usually combined with a stabilization procedure.
- Contraindications to emergent operation
- Complete spinal cord injury ≥ 24 hrs (no motor or sensory function below level of lesion) in the absence of spinal shock (i.e., the deficit is attributable to a complete spinal cord injury and not a temporary condition due to spinal shock). Bulbocavernosus reflex is generally used as a guide to the presence of spinal shock (see Bulbocavernosus reflex)
- Medically unstable patient
- Central cord syndrome: controversial
- Evidence that early surgery is not superior to late surgery
Modified recommendations of Schneider
- Complete spinal cord lesions, no study has demonstrated improvement in neurologic outcome with either open decompression or closed reduction.
- Surgery is reserved for incomplete lesions with extrinsic compression following maximal possible reduction of subluxation,
- Possibly excluding central cord syndrome show
- Progression of neurologic signs
- Complete subarachnoid block by Queckenstedt test or radiographically (on myelography or MRI)
- Compression of spinal cord (on CT/myelogram, CT, or MRI) e.g. by bone fragments or soft tissue elements (e.g. traumatic disc herniation)
- Necessity for decompression of a vital cervical root
- Compound fracture or penetrating trauma of the spine
- Acute anterior spinal cord syndrome
- Non-reducible fracture-dislocations from locked facets causing spinal cord compression
Q&A
- What is the purpose of awake fiberoptic intubation in a patient with cervical spine injury?
- The awake fiberoptic intubation is to confirm that no new neurologic deficit has been incurred during the intubation process.