If the patient has too much gastric pressure from a hiatal hernia, we have to repair that wall by performing a fundoplication. To do a fundoplication, we have to wrap around the entire stomach. Gastric bypass is considered an anti-reflux surgery. Instead of thinking about a fundoplication, you can think about a roux-en-y from the beginning instead of gastric sleeve surgery, which typically worsens acid reflux/GERD. When patients have a previous fundoplication, we have to undo the fundoplication in order to get the gastric sleeve done correctly before redoing the fundoplication.