Sotera Wireless, Inc. is a San Diego, California based health technology company dedicated to detecting early signs of patient deterioration in any acute care setting. By helping nurses detect patient deterioration early enough, further complications can be avoided.

The ViSi Mobile system enables continuous surveillance monitoring of patients with minimal impact to clinical workflow.


Design the GUI components for the ViSi Mobile system:

  • ViSi Mobile Monitor
  • Central Station

ViSi Mobile Monitor

The ViSi Mobile monitor (PWD) is a body-worn vital sign monitor that measures a patient’s vital signs (e.g. blood pressure, SpO2, heart rate, respiratory rate, and temperature) while simultaneously characterizing their activity state (e.g. resting, walking, convulsing, falling) and posture (upright, supine).

Remove Viewing Device

The Remote Viewing Device (RVD) is a desktop computer that allows continuous surveillance of all patients being monitored from a single location.


The PWD is a low-resolution touchscreen device that has 12 fixed touch-zone areas (four across / three down). The screen is 160px x 128px with each touch-zone being 40px x 42px. Space on the screen is very limited.

Part of the top row is taken up with a banner area for information text, This reduces the size of buttons displayed in the top row. Icons on the buttons needed to be very simplistic but still recognizable.

Due to the international market, the use of words was restricted to essentials. Icons were used where possible.


Storyboard: Pause/Resume Monitoring
Storyboard: Care Unit Display

Start/Resume Monitoring

When the ViSi Mobile Monitor is connected to a patient and monitoring is initiated, the clinician selects the patient’s name from a list of patients. The list is populated from the facility’s ADT system and contains all patients who are assigned to the care unit and not in a current state of active monitoring.

Starting a new or resuming a paused monitoring session uses the same workflow to provide consistency for the clinician. Any paused monitoring session may be resumed on a different monitor to the one it was paused on.

Pause/Stop Monitoring

When all cables are disconnected from the ViSi Mobile Monitor, monitoring is paused or stopped and the monitor may be removed from the patient.The monitor may be taken off for numerous reasons: shower, physical therapy, patient being discharged, etc.

  • When the patient’s identity was assigned prior to the last cable being disconnected, the monitoring session is automatically paused.
  • When the patient’s identity was NOT assigned prior to the last cable being disconnected, the monitoring session is stopped. There is a short window of opportunity to reconnect the sensors and preserve the monitoring session.

A paused monitoring session may be resumed at any time. If the session is resumed within 10 minutes, this is classified as a “device swap” event and additional functionality occurs.

Original Implementation

At the time when “bumping” iPhones to transfer data was cool and novel we decided to leverage this “cool” factor and implement the same mechanism to pair two monitors in order to complete a “swap”.

The reliability of pairing two monitoring through a bump was dependent on the two monitors communicating with the server and recognize the request to bump simultaneously.

Whereas the iPhone can rely on a full cellular network to talk between phones, the ViSi Mobile monitors were reliant on already “overworked” hospital networks. Once in production, frequent network communication failures occurred and the clinicians became increasing frustrated with the user experience.

Design Elements

Colour Scheme

The choice of colours is restricted by the FDA and standard practices within the healthcare industry:

Vital Signs:

Heart Rate


(0, 255, 50)



(255, 0, 0)



(255, 255, 0)



(0, 255, 255)



(255, 255, 255)

Physical/Technical Alarms:



(0, 255, 50)



(255, 0, 0)



(255, 255, 0)

Alarms Paused


(255, 166, 0)

At Sotera we used flashing red/white to highlight the most critical alarms.