  We present the design of a mixed reality (MR) telehealth training system that
aims to close the gap between in-person and distance training and re-training
for medical procedures. Our system uses real-time volumetric capture as a means
for communicating and relating spatial information between the non-colocated
trainee and instructor. The system's design is based on a requirements
elicitation study performed in situ, at a medical school simulation training
center. The focus is on the lightweight real-time transmission of volumetric
data - meaning the use of consumer hardware, easy and quick deployment, and
low-demand computations. We evaluate the MR system design by analyzing the
workload for the users during medical training. We compare in-person, video,
and MR training workloads. The results indicate that the overall workload for
central line placement training with MR does not increase significantly
compared to video communication. Our work shows that, when designed
strategically together with domain experts, an MR communication system can be
used effectively for complex medical procedural training without increasing the
overall workload for users significantly. Moreover, MR systems offer new
opportunities for teaching due to spatial information, hand tracking, and
augmented communication.
