Brief Answer:
As discussed in details below.

Detailed Answer:
Hi.
Thanks for your query.
Noted the history well and understood your concerns.
I can understand the concerns you have raised.
To answer your queries:
Gastric band is not known to cause hiatal hernia.
Obesity is one of the most important reason for hiatal hernia.
Repair depends upon the type and grade of hiatal hernia and usually done if medications fail to resolve the problems.
Surgery if needed is done under general anesthesia.
Both the procedures can be done in one sitting provided there is need and the on-the-table findings decide the exact course of surgical management as decided by your Surgeon.
Surgery has its own complications and benefit and should be weight against each other.
Recovery time: usually a few weeks.
But the timing depends upon a mix of many a factors.
You can search online, ask the patients who have undergone the surgery in your area or the groups of patients if any in your area. Search and let me know the names of the Surgeon or centers so that I can guide you better.
Medical information are always kept secretes so no worry on this aspect.
Surgeries are always done for the best effects hence the outcome is usually always positive.
So go ahead.
Reduce the anxiety and stress.

I hope this answers your queries.
Please feel free to ask for further relevant queries if you feel that there is a gap of communication.

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