If you intend to repaint the kitchen you may choose an easier route than scratching off the old paint. You will need to create a surface which adheres to both the gloss and the your new covering. To do this, use PVA, usually 5:1, that is 5 parts water to 1 part PVA, however, if you feel a stronger mix is called for don't be afraid to do that, however the 5:1 mix should be fine for most applications. In the event you aren't familiar with PVA, it is a general purpose adhesive/sealer used extensively in the builder industry. You can get this from most DIY centres or shops. If you look on the instructions on the back of the tin it should give you instructions for your type of application.
If there are lifted areas of the old gloss, seal the paint as previously suggested, then apply a filler. There are a wide range of these now-a-days, some you apply with a roller then remove the excess with a wide scrapper to leave an almost perfect wall.