Two ways to come close, but not true sentiment. Frist you can use the transcription notification topic to listen to specific words or phrases using a web service and the Notifications API. This could trigger a notice to the supervisor through an API call.
Second, you could use CoPilot NLU to look for phrases and pop a script that could activate a notification to the supervisor.
The notifications would be either an SMS or Email that could contain a link to the conversation. I don't know of an API that could generate a desktop alert, but 3rd-party apps could do that.