Stomach issues 1 1/2 years after anterior spinal fusion

My husband had an anterior spinal fusion (L4-L5) in September 2007. He developed postoperative ileus following the surgery because he was given food to soon. His stomach became extremely distended, and he was in intense pain for approximately 36-48 hours. When his bowels got to moving again, they moved very quick, since the doctor had given him a medley of laxatives. Things still didn't even get moving for a good 12 hours after they had given him an enema, so his digestive system seemed to have been at a stand still.

What I am wanting to know is if this type of instance can have lingering effects on a person's digestive system. Since he has had the surgery, he is having gas issues and constipation on a regular basis. His stomach will get distended and will be very painful, making it hard for him to breath. He is an athlete, actually a wheelchair racer, and this is having a very significant impact on his racing, for obvious reasons. I don't know for sure that this is related but he did have one incident in a race where he vomited up a small amount of a very very dark bile-like substance. He did not consume anything before the race because of the issues he had been having.

He has been a T6-T7 incomplete paraplegic for 23 yrs, since he was 10 yrs old, but he has never had problems like this.