First start with reading the clinical scenario and try to guess what are the possible acid base conditions . THEN read the arterial blood gases levels.? You can use this simple guide for Acid Base balance interpretation. http://www.real-doctors.com/forums/index.php?topic=71.0
Clinical details An elderly woman from a nursing home was transferred to hospital because of profound weakness and areflexia. Her oral intake had been poor for a few days. Current medication was a sleeping tablet which was administered by nursing staff as needed.
Admission biochemistry (in mmol/l): Na+ 145, K+ 1.9, Cl- 86, bicarbonate 45, anion gap 14 and a spot urine chloride 74 mmols/l.