Damage to the diaphragm is not likely the cause of your symptoms. Inhaling toxic fumes can cause damage to the airways, the airsacs, the area in between the airsacs and the blood vessels, or a combination of these.
You should not undergo anesthesia until you see a lung and a diagnosis is made. You should have a complete evaluation of your lungs by a lung specialist. This may include pulmonary function tests, chest x-ray and a CT scan. A bronchoscopy and/or a lung biopsy may be required to make the specific diagnosis. Lung biopsy is a procedure where a tube called a bronchoscope is passed through your nose into your windpipe to see into your lungs. With the bronchoscope tiny pieces of lung tissue can be taken for further testing. This is called a lung biopsy. It is done to be certain about the diagnosis. Biopsy provides the specific answer that the CT scan cannot. When done by a skilled doctor, risks and concerns are infrequent.
You need to speak with the surgeon about your prior experiences with anesthesia and your current respiratory condition(s). It is VERY important for any doctor who is going to perform ANY procedure on a patient to have such information, so the doctor can decide whether to postpone the procedure, do further evaluation, or is able to proceed keeping all the information you provide in mind.
I am sorry ot hear that you have had so much trouble. I hope your doctors can help figure out what is wrong and how to improve your health. Best of luck!
Aloha,
Starion