Mother in law has breathing problems and is currently on oxygen she was just diagnosed with internal mrsa, her dr.said he would schedule her an appt ?

Depends on problem: Mrsa is an infection but can be anywhere in body. Not sure if you have internal MRSA right? If in the lung then a staph infection. Mostly with structural lung disease or immune issues(comorbidities). On oxygen because of pneumonia? Need to eval her lung function and reason why on o2. Many reasons for this cardiac /vascular/anemia etc. Need more information. Keep md appointment.