@marciakeren , welcome. I actually gasped out loud when I read that you got an obstruction on a transcontinental flight...I'm almost afraid to travel any more, for fear that that could happen (and I used to be a travel writer!).
How long have you been having the obstructions, and do you know what causes them? Do you have a gastroenterologist? My obstructions are caused by adhesions from several abdominal surgeries (I also think that gluten MIGHT aggravate the situation by causing inflammation, so I've been gluten-free for years). I finally figured out that the problem is really a mechanical one--my sbo's are NOT triggered by what I eat (I still get them even though I'm gluten-free)...it's just that sometimes the adhesions get stuck together or something so that nothing can pass through. So far I have not been able to get answers about what makes this suddenly happen, but the bottom line is that, for me at least, the priority is eating healthy food that will be digested quickly and easily--reducing the chances of anything getting stuck behind the place of obstruction. I've posted a lot here about how and what I eat these days to try to avoid trouble, or at least make obstructions SOMEWHAT more manageable. I think I've had some success. I really don't think it matters if you're vegan or anything else--if there is food in your digestive tract--especially larger, harder to digest pieces--it's going to cause problems if you get an obstruction.
But, again, you need to know what's causing your obstructions. I strongly suggest that you go to an ER if you have one again (if you don't already do that--I know it would be hard if you're traveling!). They can be very dangerous, and a CT scan or something might help determine where the problem is.