Ultrasound-Guided Regional Anesthesia Using a Head-Mounted Video Display: A Randomized Clinical Study.

BACKGROUND

Ultrasonography is increasingly being used in every field of medicine, especially regional anesthesia. To successfully perform the procedure, a knowledge of anatomy and ultrasonoanatomy as well as technical 3D hand-eye coordination skills are required. Medical practitioners who use ultrasound devices to perform regional blocks have to correlate the position of the ultrasound probe on the patient, needle position, and ultrasound picture. To achieve that, the practitioner has to intermittently look between the patient and the ultrasonography screen. This requires extra head rotations, increasing the time and complexity of the procedure. Newer technologies are available that can alleviate the need for these extra head movements, such as head-mounted displays (HMDs), which are connected to the ultrasonography machine and project the ultrasonography picture onto the HMD goggles so that the provider can see the monitor without unnecessary head rotations.

OBJECTIVE

Our theory was that the use of the HMD goggles would decrease the overall procedure duration as well as provider head rotations.

STUDY DESIGN

This was a randomized clinical study.

SETTING

The research was conducted at an academic medical center at the University of Texas Medical Branch, Galveston, TX.

METHODS

We secured Institutional Review Board (IRB) approval to perform the study. We chose an HMD, which can be mounted on the head like regular goggles. By connecting the HMD with the ultrasonography machine, the ultrasound picture can be projected directly in front of the physician's eyes. Twenty-four patients were randomized to receive a regional anesthetic performed by anesthesiology residents using a conventional ultrasound-guided approach or using the HMD in addition. We measured the number of attempts, head rotations, and time needed to obtain a satisfactory nerve stimulation in addition to outcomes and adverse effects. Our data were interpreted by our statistician with P < .05 indicating statistical significance.

RESULTS

Regional anesthetics performed with the HMD were significantly faster (59.08 vs 175.08 seconds) with significantly fewer head movements (0.83 vs 4.75) and attempts (1 vs 1.42). There were no significant differences in patient demographics, type of regional anesthetic, level of resident training, or outcomes. No complications were noted.

LIMITATIONS

A limitation of our research is that neither observers nor providers were blinded to the way blocks were performed. This would have been practically impossible because participants had to wear an HMD.

CONCLUSIONS

The HMD could provide advantages in regional anesthesia by decreasing the time and attempts and improving ergonomics. These findings can be easily translated into other ultrasound- or optic/camera-guided procedures outside of regional anesthesia, such as vascular access or laparoscopic surgery.IRB: UTMB IRB #12-143.