Feasibility of the head-mounted display for ultrasound-guided nerve blocks: a pilot simulator study

The head-mounted display (HMD) has the potential to improve the quality of ultrasound-guided procedures. The aim of this non-clinical crossover designed study is to evaluate the feasibility of the HMD for ultrasound-guided nerve block. Eight experienced anesthesiologists performed ultrasound-guided peripheral nerve blocks on a training simulator with a standard approach and with an upside-down approach. Each approach was performed with a control conventional method and with an HMD. The ultrasound image and operating field were recorded by video camera. The procedure time and fractional percentage of time with the needle visible on the ultrasound image were determined. The needle insertion times were 10.4 ± 7.2 s with the control method and 6.8 ± 5.3 s with the HMD method for the standard approach (p = 0.03), and 18.1 ± 10.1 with the control method and 11.8 ± 9.5 s with the HMD method for the upside-down approach (p = 0.002). The fractional percentages of time with the needle visible on the ultrasound image were 34.1 ± 20.9 with the control method and 56.5 ± 13.6% with the HMD method for the standard approach (p < 0.001), and 20.1 ± 13.4 with the control method and 38.2 ± 21.2% with the HMD method for the upside-down approach (p = 0.001). In conclusion, this pilot study using a simulation model indicated that the use of an HMD shortened the procedure time and improved the needle visibility on ultrasound.