Pyloric spasms

My son has been diagnosed with both severe GERD and pyloric spasms.  I am having a hard time finding information about pyloric spasms, however, and I'm wondering if anyone else can relate to this?  My son is 7 1/2 months old, and we are having a terrible time with him vomiting all the time.  His vomiting is not only affecting our "laundry" situation, but he sleeps poorly due to his having to wake up and vomit all the time, and his motor skills are starting to become delayed because it hurts for him to sit up or roll on the floor.  Food allergies have been ruled out, though he could have sensitivities....he seems to vomit everything, though, including solids.  He's had an Upper GI and endoscopy.  We've tried all the "simple" GERD solutions (e.g., elevation, adding rice cereal to milk, etc.), none of which really help. Is anyone dealing with this or has dealt with this before?  
Thanks!