As part of the v2-to-FHIR project we are mapping commonly used fields in key v2 messages to FHIR resources so that messages can be transformed into bundle of FHIR resources. NTE-4 is the Comment Type field but there is no cognate existing data element in FHIR. We suggest that a standard extension to Annotation data type be created to allow exchange of this concept. 

We suggest a CodeableConcept value possibly using value set http://terminology.hl7.org/CodeSystem/v2-0364 with a binding other than Required (as table 0364 is user defined and the v2 values are suggestions only).