What Causes Nausea, Vomiting And Indigestion With History Of Horner's Syndrome?

MY HUSBAND HAD NECK SURGERY 4 YEARS AGO HAD HORNERS SNDRONE POST OP WHICH HE HAS REGAINED SENSATION PAST 3 YEARS HAS HAD PROBLEMS WITH NAUSEA AND VOMITING VOMITING UNDIGESTED FOOD THAT HE HAS EATEN 24-48 HOURS AGO HAD GALLBLADDER REMOVED 2 YEARS AGO ONE DR SAID HE PROBABLY HAS PROBEM WITH HIS NERVE GASTRIC PARESSIS COULD THERE BE SOMETHING ELSE GOING ON