Review of: Werman HA, White LJ, Herron H, et al: "Clinical Clearance of Spinal Immobilization in the Air Medical Environment: A Feasibility Study." Journal of Trauma. 64(6):1539-1542, 2008.
The researchers decided to use this flight program in Akron, Ohio to examine the feasibility of using what they term a "spinal clearance" protocol to determine if they could either remove the patients from spinal immobilization prior to transport or avoid spinal immobilization. They did not actually change their practice for this study. They transported 329 patients who were immobilized and performed the clearance assessment while en route to the trauma center.
They utilized the most common set of what I call "selective spinal" immobilization criteria that includes the absence of all of the following clinical findings: (1) abnormal level of consciousness; (2) evidence of intoxication; (3) distracting painful injury; (4) spinal tenderness or pain or (5) abnormal neurologic examination.
Only 40 of their patients met the criteria for non-immobilization. However, four of these were found to have spinal fractures. One of these four was unstable. Of the patients who didn't qualify for non-immobilization, 49 (15%) had spinal fractures with 12 being considered unstable.
The authors concluded spinal clearance wasn't appropriate for air medical services.
Selective spinal immobilization continues to be a controversial issue. Although the emergency department data strongly supports it, only a handful of prehospital studies examine its safety in the hands of EMS. The problem for EMS studies is that the incidence of spinal injury is relatively low; and therefore these studies require large numbers of participants to determine the specificity (few false negative) and sensitivity (few false positives). Of the two, specificity is the most clinically important as the consequences of missing a spinal injury could be significant.
A further analysis of the patients transported by this air medical service reveals almost half of their patients had a Glasgow Coma Scale less than 15 (not alert), and 38% were hypotensive. Although the majority of their patients who met the criteria for not being immobilized didn't have what you and I would consider being significant distracting injuries, they did have a high incidence of thoracic and abdominal trauma. The average Injury Severity Score (ISS) was 12.6 where 16 is major trauma.
Therefore, the take-home message, at least from this study, is that patients who meet your service's criteria for air medical evacuation should have spinal immobilization since this group of patients may have occult injuries that disqualify them from routine use of selective spinal immobilization protocols.