I am sorry to learn of your husband’s serious medical problems. There are many possible causes of such a cough in his circumstance, including pneumonia (despite the report of nurses not hearing “anything” in his lungs), heart failure, and abnormal swallowing with recurrent aspiration of food or liquid into his lungs, perhaps a result of his failing general health.
I suggest that you arrange a meeting with his doctor(s) to discuss these issues and, more importantly, to discuss end-of-life care, including but not limited to Hospice Care. You should arrange to be accompanied by a close friend or relative when you meet with his doctor and that you request that he/she speak with complete candor about your husband’s condition and his prognosis.
Good luck
Thank you for your response Doctor. It was very helpful. My husband has since had an x-ray and his lungs are clear with no visible fluid buildup. He drinks thickened liquids and I think some of it is too thick for him. Anyway he did cough up some phlegm on Sat. and was much better on sun. Then on mon. cough returned.