It depends on what you are using from the LOINC release. Some of the descriptions such as the LOINC Long Name may be updated with each release. There have been technical changes from time to time too which are in the release notes.
We use the Canadianized version of LOINC – pCLOCD and do have a process that compares the new version and latest version, the basics would be the same for LOINC. The process produces 3 reports: 1) identifies net new terms and will overwrite our local codes if one has been created and included in the newest version 2) identifies terms that are not in the new version that were not in the last version (this should ideally not happen, but has on occasion). 3) identifies changes to term attritubutes for terms that are mapped to our local LIS codes. We use a locally developed tool for our mapping and have this process as a separate function within, we used to do this on spreadsheets which was very laborious. Saskatchewan uses approx 4500 LOINC codes and on average need to review about a dozen terms per version update.