I dont think this is only related to database changes.
If you are not the Senior Architect or Database Programmer in your team, any changes you make to design & implementation of code or SQL or DB tables or any other artifacts, should be reviewed and approved by other team members - either peers or seniors.
Are you hesitant to do this? Is there no formal review process already in place?
Update:
In your case, it depends on what impact the changes have. Are you making a small change like the length of a single VARCHAR2 column or adding new columns to the table which need buy-in from the front-end developers too? In any case, I'd say discussion is better than not doing so - and regretting later