Prehospital Management

Prehospital management has dramatically improved the neurologic status of patients on arrival to hospital and sets the stage for enhanced recovery, attributable to both improved emergency response infrastructure and prehospital training. Rigid spinal immobilization has become standard in any suspected spine or spinal cord injury. In children under 13, this is best accomplished by backboard, sandbags (or other lateral cervical spine stabilizers), and taping. Nevertheless, spinal immobilization should be removed at the earliest and safest time possible.

Early transfer to a specialized pediatric center has been associated with significant reductions in mortality and hospital length of stay, and increased neurologic recovery. Because cervical and even thoracic spinal cord injury can result in airway and pulmonary compromise, respiratory support resources should be available during transport.

Pharmacologic Intervention

Administration of the steroid methylprednisolone within 8 hours of adult SCI may improve motor and sensory scores in patients. In response to SCI, the spinal cord swells, and methylprednisolone is administered to reduce secondary injury in the hope of preventing further neural injury. The National Acute Spinal Cord Injury Studies are controversial because they failed to address potentially important recovery-influencing details regarding surgical intervention and rehabilitative therapies. Furthermore, later analysis revealed that these studies did not demonstrate an improvement in patients’ primary outcome measures, which indicates that the improved recovery could be due to random events. Because these studies are not entirely credible, evidence is lacking to decisively recommend the use of methylprednisolone following acute SCI. In addition, methylprednisolone was never studied in children, thus its use cannot be advocated.

Spectrum of Medical Complications

Every organ system can be affected by SCI, irrespective of whether the system is primarily injured in the traumatic event. To reduce the number and severity of overall medical complications, the patient should be transported to a pediatric level I or II trauma center with immediate access to a trauma team and imaging capabilities including computed tomography (CT) and magnetic resonance imaging (MRI). Once medically stable, and preferably within 24 hours of the injury, movement to a specialized pediatric SCI injury center with coordinated state-of-the-art care, if not a component of the level I or II trauma center, is advised. Thus, constant vigilance must be maintained to prevent these complications and to manage them as rapidly and as comprehensively as medically feasible when they do occur.

Because the incidence of pediatric SCI is quite low (< 1% of all new spinal cord injury cases per year), the incidence of medical complications in children is not well documented. However, with the exception of pulmonary embolism (PE), it should be anticipated that pediatric medical considerations are not dissimilar to those of adults.

Pulmonary Considerations

The respiratory system is uniquely susceptible to SCI because primary neurologic dysfunction profoundly affects respiratory physiology directly, as well as indirectly. Cervical injury is more commonly associated with pulmonary complications, as 84% of all respiratory complications are the result of C1-4 injuries. However, more than 60% of patients with lower-level injuries develop pulmonary problems, so these may also occur from thoracic-level injuries. Pulmonary complications are the single most common cause of morbidity and mortality after pediatric SCI.

The muscles of respiration include the abdominal, intercostal, diaphragm, and cervical accessory muscles. The abdominal muscles are the primary muscles of active expiration and account for over 50% of expiratory capacity. Thus, thoracic SCI with abdominal muscle paralysis may lead to ineffective expiration, excessive end-tidal volumes, and, subsequently, a diminished lung capacity.

The intercostal muscles play an important role in stabilizing the chest wall during inspiration. Their paralysis results in a functionally flail chest, in which the chest wall collapses during inspiration and expands during expiration, resulting in an overall loss of tidal volume.

The diaphragm muscles account for approximately 50% to 60% of the inspiratory force generated. When the other muscles of respiration are nonfunctional, however, the diaphragm assumes 100% of the workload and may rapidly fatigue.

Overall, generalized muscle weakness associated with midthoracic injury levels contributes to diminished contraction force for effective coughing and clearing of secretions. These muscle abnormalities, singly or in combination, may ultimately significantly decrease functional residual capacity, tidal volume, and inspiratory and expiratory volumes, while markedly increasing residual lung volumes. Nasotracheal suctioning is often insufficient to mobilize secretion, and consequently, expiratory aids such as mechanical insufflation-exsufflation or quad coughing are necessary.

Remember that the vital capacity and the tidal volume of the quadriplegic patient are greater in the supine position than in the upright position. In the supine position, the weight of the abdominal contents helps in forcing the diaphragm rostrally, which leads to a decrease in residual volumes.

Despite attention to these details, some children may require intubation for respiratory support. The two primary indications are the inability to ventilate effectively (partial pressure of carbon dioxide > 50 mm Hg) and the inability to oxygenate adequately (partial arterial oxygen pressure < 80 mm Hg). It is critical to monitor these blood oxygen and carbon dioxide levels via pulse oximetry or arterial blood gas measurement early during SCI management.

Endotracheal intubation is often required before the location of an injury can be determined, so it is essential to keep the cervical spine as stationary as possible while securing the airway in case of a cervical-level injury. Succinylcholine is the recommended neuromuscular blocking agent to use during intubation, but only within the first 48 hours after injury due to the risk of hyperkalemia.

Except for quadriplegics with injury at very high levels, most pediatric SCI patients can be weaned from ventilatory support during acute hospitalization.

Despite attention to these details, atelectasis and ventilator-associated pneumonia are still common in the SCI population, and, thus, constant vigilance is of utmost importance to diagnose and treat pneumonia rapidly. Preventative strategies that reduce the risk of ventilator-associated pneumonia include the maintenance of the child in a semirecumbent position, the assessment of the child’s readiness for accepted ventilator weaning protocols, and the use of an orotracheal route of intubation. The use of prophylactic antibiotics is not encouraged, even in children who require prolonged intubation or tracheotomy. Routine use may increase the occurrence of antibiotic-resistant infection.

Another potential pulmonary complication of SCI is sleep apnea. Spinal cord tracts that lie in the rostral cervical spinal cord regulate automatic respiration. If these pathways are significantly damaged, only voluntary respiration (which is dependent on consciousness) is possible, and breathing may cease during sleep. One should maintain a high index of suspicion of this syndrome in any patient with a high cervical SCI. An apnea monitor or pulse oximeter should be used on a continuous basis for 7 to 10 days after injury in such children.