FYI Just posted medium on methods to shorten FHIR Messages. https://medium.com/care-connect-fhir/care-connect-fhir-shorthand-references-11c1503df99a
Personally I see FHIR working more as a RESTful API and don’t see FHIR Message taking over from existing ITK HL7v2 messaging within a hospital but we have areas with little standardisation in UK health or areas where introducing HL7v2 would be unsuitable (e.g. for handling documents the use of MDM^T02 Original Document Notification and Content isn’t huge). FHIR could be very useful in this gap (especially with services like eRS API, NRLS and GP Connect Send Document either live or coming soon).
However the size of FHIR messages can be a lot larger than equivalent HL7v2 messages, the blog looks of ways of solving this.
p.s. hopefully releasing blogs on handling documents (pdf, images and html) within a hospital, soon.