A critical value
A few results, very far from the reference range, may call for a quick medical decision. The laboratory calls them critical values. Their list and thresholds are set by the biologists.
Who calls whom
The biologist calls the prescribing doctor. If they can't be reached, the biologist calls the patient, then the doctor on call. The person reached reads the value back, and the call is recorded with its time.
Why never in a message
A result like this is discussed with a person, not in a notification. Neither the laboratory's messages nor Dalil, the AI assistant, announce a critical value.