Evaluation of Mobile Intensive Care Unit

Issue
The Healthcare Human Factors Group was engaged in the evaluation of a mobile intensive care unit designed for use by military medics in helicopters. Although it was designed specifically for the military, the unit is also valuable to other emergency transport care services because of its mobility. The unit was designed such that medics interact with it via a small visual display and audio/visual outputs. Given that users are expected to effectively control and monitor this safety-critical system, it is paramount that the user interface be well-designed to facilitate correct actions and prevent or discourage actions that could result in errors.

Methods
Expert evaluation of an initial prototype of the mobile Intensive Care Unit (ICU) was performed to ensure that subsequent designs conformed to established usability principles. Subsequently, a helicopter simulation was constructed which replicated the exact dimensions of the army helicopter for which the mobile ICU was developed. Usability testing of the mobile ICU was conducted with realistic scenarios in a helicopter-simulated environment. Military medics were enlisted to participate in the usability tests. Specifically, while in the helicopter simulator, military medics interacted with the mobile ICU while “thinking aloud” and being observed by facilitators. Their actions and comments were analyzed.

Results
Based on the user testing results, the Healthcare Human Factors Group provided recommendations on how to optimize workflow to minimize the cognitive load placed on users when attempting to remember the different steps required to successfully interact with the device. Quantitative (e.g., # of errors) and qualitative (e.g., comments) feedback highlighting the major issues requiring design improvements were also provided.