<s>[INST] My 19 year old son had a bilateral lung transplant 4 years ago. He is overcoming a serious lung infection now with serious problems that no one can figure out. His symptoms are high carbon dioxide levels especially when he is on the Cpap machine. He has had a severe migraine headache for 2 weeks. he has hypercamnia. He also had very high blood pressure and heartrate. He needs to regain strength in order to have another transplant which is impossible to do with his hypercapnia. His other symptoms include ventilator with tracheostomy, high blood pressure, high heart rate. He was diagnosed with severe sleep apnea about a year ago. what explanation could there be or cause. could this be related to his adrenal gland? just ideas what to check or or how to treat would be appreciated. [/INST] Thanks for your question on Chat Doctor. I can understand your sons situation and problem. Possibility of type 2 respiratory failure due to lung infection is more. Hypercarbia is feature of type 2 respiratory failure. And it is common in respiratory infections. He is lung transplant patient, so possibility of uncommon lung infection like fungal, parasitic, multi Chat Doctor.  So he needs bronchoscopy and BAD (bronchoalveolar lavage) analysis for the diagnosis of infections. Also get done sensitivity report of BAD for guiding effective antibiotic therapy. He also needs high respiratory rate, increased expiratory time and low tide volume ventilatory strategy. So better to consult pulmonologist and discuss all these. Hope I have solved your query. Wishing good health to your son. Thanks. </s>