Hi all! I get really confused with the nursing dianosis's. We must get the main diagnosis correct, but I am having a hard time. The patient suffered a pneumothorax, but the chest tube was taken out on day of assessment, only to be diagnosed with pneumonia. Patients Chem 7 results were low CO2 levels and his O2 sats were at 90. Respirations were 24, now how do I decide between Inneffective Breathing Pattern/Impaired Gas Exchange/Impaired Tissure Perfusion???? I get so lost...I can always r/t and come up with interventions but how to I best diagnose the main nursing diagnosis? Thanks for any help