I’m working on an example of this at the moment.
My thoughts I would create a master Encounter (say emergency episode)
This would have child encounters such as:
- Triage Encounter
- Ambulance assessment encounter
- Ambulance transport encounter
- Ambulance handover encounter
These sub encounters would use Encounter.partOf to reference the master Encounter.
For a hospital, following this approach I would have:
Hospital Episode Encounter which consists of a number of speciality (e.g. Emergency, Inpatient, etc) Encounters (episode?) and these break down into other Encounters which detail the admission, transfer, discharge and other interactions with the patient. (These would correspond partly to ADT^A01, ADT^02, ADT^A03, ADT^A04 etc)
However I believe the top level Encounters (for both Ambulance and Hospital) should really be FHIR EpisodeOfCare.