I had the same thing in the beginning, following endoscopy, just before starting immunotherapy. Couldnt swallow. Secretions piled up. I coughed & aspirated upon falling asleep. Caused pneumonia twice. It was suggested that the trauma from the endoscopy/biopsy created additional inflammation and associated secretion buildup. It improved over time and now 7 mos into it, I can sleep with up so much buildup. I do intentionally regurgitate couple time daily when I feel it building up. Facing the toilet, I just bend over & employ almost a vomiting maneuver. That really helps relieve the esophageal pressure. I recently started on a pump, which allows a days worth of feeding gradually overnight. I use it for water too. Has been a positive experience. I still have complete blockage, but immunotherapy is a slower process. Just gotta be patient. Hope your wife feels improvement soon & does well with her regimen