Kaiser is a Medicare Advantage plan. This is different than just having original medicare. Kaiser has HMO and PPO and will have their own requirements for weight loss surgery. I have regular medicare and a blue cross supplement. You can determine what guidelines Medicare have for national and local. Just go under medicare centers for disease. Go under coverage determinations. Select advanced searh and enter the information and it will tell you what they will approved and under what circumstances.
I would advise you to contact Kasier directly and get their coverage quidelines.