The usability failure mode

Recommended protection

Validation

Improper connection to patient

The system might generate excessive false alarms due to improper connection to the patient.

Distinguished connection sensing

The alarm system should distinguish between connection problems and low sensor values, and provide different indications for the two types of signals.

Functional testing:

Test the alarm signals when the sensors are detached from the patient.

Excessive details

Too many details in normal monitoring might result in the user disregarding important details about the patient situation.

Patient overview

Normal monitoring should provide an overview of the data, enabling data significant to emergency situations to be salient.

Risk indication

The manufacturer should provide a visual display of a risk score. The risk score should be based on the risks of all the individual sensor risks. For example, it can be the maximal risk over all the sensors. The overview should indicate the trend, namely, how is the risk changing over time.

Usability testing:

1. Assign a patient to the system
2. Connect the patient
3. Let the user capture the patient situation, by the Overview mode
4. Let the user drill-down to capture the sensor trends.

Disturbing information signals

Information signals are used to provide indication of the sensor measurements, primarily as an active indication that there no alarm conditions exist. However they are disturbing in certain situations during normal supervision.

Avoid information signals

To avoid disturbing normal supervision, information signals should be avoided. This can be achieved if the user can trust the alarm, namely, if the alarming is reliable.

Functional testing