age gender, exercise, acid-base balance, brain lesions (hemorrhage/tumor), increased altitude, respiratory diseases, anemia, anxiety, medications, acute pain
- Profusion: can get air in but can’t get it out into body. Something that stops oxygen from being distributed.
- Ex. COPD, pneumonia (PNA)
: O2 sat (oxygen saturation) decreases. Blockage in alveoli prevents oxygen to transfer into capillary cells.