| Reason for the Action |
Failure of the watchdog may cause the system to be in
an unknown state and therefore potentially prevent alarms from being generated or logged.
Following the initial system error which triggers the watchdog, staff may observe unexpected system behaviour while the watchdog attempts recovery. The observed behaviour depends on the underlying software problem and may include:
- Inability to interact with the PIC iX user interface. If real-time waveforms, numeric data, and alarms remain operational, there is no impact to bedside or central monitoring and alarming.
- The user will not recognise the device problem before the hazardous situation occurs if the observed behaviour is: Loss of central alarming, loss of, or frozen, waveforms/data display
- Bedside monitors and Telemetry devices could generate a ‘No Central Mon’ INOP.
The failure of the watchdog may cause the system to remain in an unknown state during which central monitoring and alarming may not occur. This may also be associated with a failure of connected telemetry devices to disconnect and provide local alarming. While this harm has not been demonstrated to date, there is evidence of events involving frozen data and absent alarming occurring which required manual intervention to resolve. |