This is the ValueSet that contains all the codes in Vital Signs Units (http://hl7.org/fhir/ValueSet/ucum-vitals-common) and eICR Processing Status Reason (eCR) (http://phinvads.cdc.gov/fhir/ValueSet/2.16.840.1.113883.10.20.15.2.5.7). E.g. what you have to deal with if you get resources containing codes in either of them