Evaluation of the Head-Mounted Display for Ultrasound-Guided Peripheral Nerve Blocks in Simulated Regional Anesthesia

Background and Objectives: Anesthesiologists performing peripheral nerve blocks under ultrasound guidance look frequently back and forth between the patient and the ultrasound screen during the procedure. These head movements add time and complexity to the procedure. The head-mounted display (HMD) device is a commercially available head-mounted video display that is connected to the ultrasound machine and projects the ultrasound image onto the HMD glasses, enabling the anesthesiologist to monitor the screen without ever needing to look away from the patient. We hypothesized that the use of the HMD device would decrease the total procedure time as well as operator head and ultrasound probe movements during a simulated nerve block. Methods: The Blue Phantom was used to simulate a nerve block target. After IRB approval, verbal consent was obtained. Twenty participants, at different levels of training/experience, were asked to perform a simulated nerve block under ultrasound guidance with and without the HMD. The number of ultrasound probe and head movements and the time required to place the needle with and without the HMD were recorded. Results were analyzed using a paired t-test and significance was accepted with P<0.05. Results: Participants were significantly faster (7.1 vs 10.9 seconds) performing the simulated block with the HMD than without. Additionally, the HMD significantly decreased the number of operator head and ultrasound probe movements. Conclusions: Use of a HMD improved efficiency and human factors during simulated nerve blocks. This suggests that a clinical study to see if this observation translates into a clinical setting is warranted.