What is the evidence for pre-hospital spinal immobilization of trauma patients?

Dr. Reisman presents today’s Morning Report!

What is the evidence for pre-hospital spinal immobilization of trauma patients?

Routine spinal immobilization in trauma patients: What are the advantages and disadvantages? S. Abram, C. Bulstrode The surgeon: journal of the Royal Colleges of Surgeons of Edinburgh and Ireland 1 August 2010 (volume 8 issue 4 Pages 218-222 DOI: 10.1016/j.surge.2010.01.002)

Review: Benefits are theoretical. NNT estimated 150-392 by different authors (however, these numbers are really just prevalence of spinal injury in various cohorts, as there is no evidence for improved patient outcomes with immobilization). Possible harm to patient from immobilization include causing neurological deficits in patient with ankylosing spondylitis, raising intracranial pressure in head-injured patients, difficulty in airway management, and delayed resuscitation.

Conclusion: “Routine spinal immobilization in trauma patients has become established largely without an evidence base. The number needed to treat is unknown but large. There is a growing body of evidence documenting the risks and complications of this practice. There is a possibility that immobilization could be contributing to mortality and morbidity in some patients and this warrants further investigation.”

Kwan I, Bunn F, Roberts IG. Spinal immobilisation for trauma patients. Cochrane Database of Systematic Reviews 2001, Issue 2. Art. No.: CD002803. DOI: 10.1002/14651858.CD002803.

Cochrane review: No randomized trials of spinal immobilization in trauma patients. No evidence that pre-hospital immobilization affects patient outcome. Studies in healthy volunteers suggest that immobilization may actually cause more movement of the spine due to pain and discomfort.

Conclusion: “We did not find any randomised controlled trials that met the inclusion criteria. . . . Because airway obstruction is a major cause of preventable death in trauma patients, and spinal immobilisation, particularly of the cervical spine, can contribute to airway compromise, the possibility that immobilisation may increase mortality and morbidity cannot be excluded. . . . Randomised controlled trials in trauma patients are required . . . “

Hauswald M. Ong G. Tandberg D. Omar Z. Out-of-hospital spinal immobilization: its effect on neurologic injury. Acad. Emerg. Med. 1998;5:214–219

Hauswald compared trauma patients in Malaysia where immobilization is never performed to patients in New Mexico where immobilization is routinely performed. 454 patients total; similar characteristics except for more MVCs in patients from New Mexico. Patients who were immobilized had statistically significant higher rate of neurological deficits. Author notes that it takes 2,000-6,000 Newtons to damage the spinal cord; hanging a head unsupported only generated 40N.

Conclusion: “Comparison of spine injury patients from 2 study populations, one with out-of-hospital spinal immobilization and the other without, showed a higher rate of neurologic injury in the immobilized group. Acute spinal immobilization may not have significant benefit for the prevention of neurologic deterioration from unstable spinal fractures.”

Do current extrication techniques even prevent movement of the spine?

Shafer J, Naunheim R. Cervical Spine Motion During Extrication. West J Emerg Med. 2009; 10(2): 74-78

Shafer constructed a mock-up of a damaged vehicle and had experienced paramedics perform extrication while using motion-capture technology to measure movement of the spine. Extrication caused significantly more movement of the cervical spine than applying a collar and telling the person to get out of the vehicle without moving their neck.

Conclusion: “In those ambulatory subjects who do not complain of back pain, the least motion of the cervical spine may occur when the subject is allowed to exit the car in a c-collar without backboard immobilization. This may have implications for decreasing extrication time in the pre-hospital setting and reducing complications of long spine board use.”