Suggest Treatment For Shortness Of Breath, Weakness And Depression

My husband has been experiencing shortness of breath frequently over the last three weeks. He hasn t been able to eat a full meal because every time he takes a couple of bites, he feels bloated and hard to breathe. He s been asthmatic all his life but that has been largely under control and never affected him in this way. We ve been to the ER, his primary doctor and a GI specialist all in the past three weeks and so far no one has been able to help. His GI test came back with a diagnose of GERD and he s been on medication but that hasn t helped. He s lost 12 lbs in three weeks due to the lack of eating. He s feeling extremely weak and depressed. Any help would be so appreciated.