In Australia (self pay too) it may be different than where you are but,
1. Standard blood tests to establish base points and any comorbities (not that I probably needed comorbities my weight was high enough), also need a test for H-pylori (negative for me), if positive would have needed a course of antibiotics.
2. General anesthesia
3. Yes, but this really depends on the doctor. Some doctors do it to ensure a pattern of compliance, if someone can't do two weeks pre -op liquid/shake diet how will someone be able to manage the post-op liquid diet??
4. None for me.
Some people for various reasons have lost restriction. Tests have revealed that the sutures have become lose or undone. Reason may include non-compliance with post op guidelines, doctor inexperienced with ESG and suture placement, some people who have had a gastric balloon prior to ESG have a higher failure rate, some people with severe vomiting (due to other illnesses) which has caused sutures to loosen...and then there are the people for some inexplicable reasons the ESG has failed even though they have followed all the insructions and they have experienced doctors etc.
Some points to bear in mind for ESG: weight loss will likely be slower and lower than the surgical options (average weight loss is 20% of excess weight, some people have lost a lot more, some people have lost less), adherance to post op guidelines is vital - it will help the suture anchor points heal which will help the restriction hold tight. Like the surgical options there is a weight loss sweet spot, for the ESG it is probably the first six months to 12 months. It's tool, we need to make it work to ensure the best weight loss, this means a compliance with post op guidelines for diet and exercise, will need to change all those not so healthy eating habits particularly emotional eating.
Generally the ESG is not reversible, and it has been said that for those who choose to have a revision (where the ESG has failed) that a VSG is not a safe option (though I have seen research where such revision has been successful) - i think it may be a chase of the suture anchor points may get in the way of a VSG. Bypass seems to be the surgeons' choice for ESG revision to surgical option. Another ESG is also a viable revision.