Efficacy of an inflatable spine-board padding device in relieving pain during simulated spinal immobilization

Abstract

Study objectives: Rigid spine boards, along with other devices, are commonly used for spinal immobilization by emergency medical services. Research indicates that victims spend an average of 60 minutes immobilized, resulting in prolonged discomfort, which may prompt unnecessary radiographs. Padding devices have been shown to decrease pain in immobilized volunteers. The use of a verbal analog scale to rate pain has been validated. This study investigated the efficacy of a commercially available inflatable spine-board padding device (IPD) in reducing pain caused by spinal immobilization in healthy volunteers. Methods: This was a prospective, randomized, crossover study in a nonclinical, laboratory setting. Twenty-five healthy adult volunteers without acute or chronic back pain and not having used analgesics in the preceding 24 hours were recruited to participate. Two trials were performed on each subject, with and without the IPD (BackRaft, MedicTech, Inc.). Volunteers were immobilized using rigid cervical collars, spine boards, head immobilizers, and straps. Immobilization was performed by experienced paramedics, along with the investigators, using standardized methods and the manufacturer's instructions for inflation of the IPD. The order of the 2 interventions was randomized and timed at least 48 hours apart. Volunteers were immobilized for 60 minutes. A pain assessment was obtained immediately preimmobilization and every 15 minutes until 15 minutes after immobilization was discontinued. A verbal analog scale was used to assess pain, with subjects asked to rate their pain on a scale of 0 to 10, with 10 being most severe. The difference between pain ratings with and without the IPD was calculated for each participant at each interval. The mean difference for each time interval was then compared with zero using a paired 2-tailed t test. Results were considered statistically significant at a P value less than .05. Research suggests that a difference of greater than 1.3 units indicates clinical significance. Mean differences with lower 95% confidence intervals greater than 1.3 were thus considered clinically significant. Subjects were examined for physical injury 15 minutes after immobilization was discontinued. Results: After 60 minutes of immobilization, volunteers reported mean level of discomfort on the 0 to 10 verbal analog scale of 1.52, with the IPD versus 4.88 for the control session. Mean reduction in pain scores increased steadily from −0.04 at zero minutes to 3.36 at 60 minutes. Reduction in pain was statistically significant at all intervals from 15 minutes through 60 minutes. Using the criterion of greater than 1.3 for the lower 95% confidence interval, pain reduction at 45 and 60 minutes was also clinically significant. There were no physical injuries in any volunteer. Conclusion: Healthy volunteers reported statistically significant reduction in pain at 15 through 60 minutes when an IPD was used during spinal immobilization. Using a criterion of greater than 1.3 units, reduction in pain at 45 and 60 minutes was also clinically significant. The IPD was effective in decreasing discomfort during spinal immobilization in healthy volunteers. Clinical studies in immobilized trauma victims are indicated.