Vascular access: comparison of US guidance with the sonic flashlight and conventional US in phantoms.

PURPOSE

To prospectively evaluate whether ultrasonography (US)-guided vascular access can be learned and performed faster with the sonic flashlight than with conventional US and to demonstrate sonic flashlight-guided vascular access in a cadaver.

MATERIALS AND METHODS

Institutional review board approval and oral and written informed consent were obtained. The sonic flashlight replaces the standard US monitor with a real-time US image that appears to float beneath the skin and is displayed where it is scanned. In studies 1 and 2, participants performed sonic flashlight-guided needle insertion tasks in vascular phantoms. In study 1, 16 participants (nine women, seven men) with no US experience performed 60 simulated vascular access trials with sonic flashlight or conventional US guidance. With analysis of variance (ANOVA) and power-curve fitting, improvement with practice rate and mean differences between techniques and tasks were examined. In study 2, 14 female nurses (mean age, 50.1 years) proficient with conventional US performed simulated vascular access trials on three tasks with the sonic flashlight and conventional US. With random assignment, half the participants used the sonic flashlight first and half used conventional US first. Mean performance with each technique and that with each task were compared by using ANOVA. In study 3, feasibility of sonic flashlight guidance for access to internal jugular and basilic veins was demonstrated in a cadaver.

RESULTS

For study 1, learning rates (ie, decrease in access time over trials) did not differ for vascular access with sonic flashlight and conventional US. Overall, participants achieved faster vascular access times with sonic flashlight guidance (P < .007). In study 2, participants performed procedures faster overall with the sonic flashlight (P < .02) and found the sonic flashlight easier to use. In study 3, sonic flashlight-guided vascular access was gained in the cadaver.

CONCLUSION

Learning and performance of vascular access were significantly faster with the sonic flashlight than with conventional US, and vascular access could be gained in a cadaver; the sonic flashlight is ready for clinical trials.