Talk to Pulmonologist / Lung on Bed Bound Patient White Sputum

My mother is 75 years old she is bed bound since one year she has been admitted for one day in icu due to low saturation and chest congestion her chest is clear but still since very long she has this problem of spitting white sputum very thick and clear after or due to eating she is taking meds for acid reflux but still the problem is there she even sits for half or one hour after eating