Comparison of three prehospital cervical spine protocols for missed injuries.

INTRODUCTION: We wanted to compare 3 existing emergency medical services (EMS) immobilization protocols: the Prehospital Trauma Life Support (PHTLS, mechanism-based); the Domeier protocol (parallels the National Emergency X-Radiography Utilization Study [NEXUS] criteria); and the Hankins' criteria (immobilization for patients <12 or >65 years, those with altered consciousness, focal neurologic deficit, distracting injury, or midline or paraspinal tenderness).To determine the proportion of patients who would require cervical immobilization per protocol and the number of missed cervical spine injuries, had each protocol been followed with 100% compliance.

METHODS: This was a cross-sectional study of patients ≥18 years transported by EMS post-traumatic mechanism to an inner city emergency department. Demographic and clinical/historical data obtained by physicians were recorded prior to radiologic imaging. Medical record review ascertained cervical spine injuries. Both physicians and EMS were blinded to the objective of the study.

RESULTS: Of 498 participants, 58% were male and mean age was 48 years. The following participants would have required cervical spine immobilization based on the respective protocol: PHTLS, 95.4% (95% CI: 93.1-96.9%); Domeier, 68.7% (95% CI: 64.5-72.6%); Hankins, 81.5% (95% CI: 77.9-84.7%). There were 18 cervical spine injuries: 12 vertebral fractures, 2 subluxations/dislocations and 4 spinal cord injuries. Compliance with each of the 3 protocols would have led to appropriate cervical spine immobilization of all injured patients. In practice, 2 injuries were missed when the PHTLS criteria were mis-applied.

CONCLUSION: Although physician-determined presence of cervical spine immobilization criteria cannot be generalized to the findings obtained by EMS personnel, our findings suggest that the mechanism-based PHTLS criteria may result in unnecessary cervical spine immobilization without apparent benefit to injured patients. PHTLS criteria may also be more difficult to implement due to the subjective interpretation of the severity of the mechanism, leading to non-compliance and missed injury.