A7 - Anesthesia System (Electronic Fresh Gas Control)
Mindray Biomedical
Role: Design Director ID/UI, Research, Concept
Background
The A7 Anesthesia System is the first in the Mindray line to employ electronic fresh gas control through the use of digital encoders and a touch-screen interface. Traditional systems require the operator to calculate settings for desired ratios using of gas mixtures which are then set using analog knobs geared to valves and indicated by rotameters.
A system with electronic fresh gas control allows the clinician to deliver anesthesia more precisely and in more sophisticated or difficult procedures in which “low flow anesthesia” is required.
The Challenge
Without “Electronic Fresh Gas Control” Mindray could not compete against market leaders such as GE and Drager in operating rooms where “Low Flow Anesthesia” was being performed. However, all competitors used a similar workflow to set the desired gas flow and ratio which involved 6 actions using a combination of "selector buttons” and a “multi function” digital encoder. As an upstart competitor Mindray’s marketing team did not believe they could compete with a device that operated in a similar fashion.
The use of multi-function knobs, a vestige of non-touch interfaces, is still clung to despite the inefficiency of the workflows associated with them.
The image above indicates the "touches" necessary to adjust the flow rate and oxygen percentage on the GE Avance. These are among the most high frequency adjustments made on an Anesthesia Machine.
Theory of operation pitched to the product team
The Concept
Breaking away from the conventions of the market leaders, I proposed an alternate means of controlling the fresh gas flow reducing the number of actions necessary to set the ratio from 6 to 2 and making the operation far more intuitive.
Formative Testing
With a novel approach to delivering fresh gas it was critical to put the concept in front of anesthesiologists as early in the development process as possible. Changing the way in which clinicians interact with devices from long established conventions can be tricky. I’ve found that older, more experienced clinicians often resist change that younger clinicians readily accept. It’s essential to ensure that any change makes a meaningful improvement to workflow.
My team collaborated with software engineers to build a software / hardware prototype of the interface for user testing. At this point I delegated the detailed design of the Fresh Gas interface and its associated sub menus and settings to a member of my UX team.
Testing at Emory University
Addressing Risk
Moving our system from an analog control to a digital control required that we find a way for the anesthesiologist to continue to supply a patient with fresh gas (oxygen/air/nitrogen) even in the event of electronic failures or power loss. Selling the overall system concept hinged on ensuring the anesthesiologist would be confident that they could keep their patients breathing even in the event of a catastrophic failure.
I proposed a design for a backup analog system that could be both automatically or manually deployed.
Backup Fresh Gas Control Prototype
