35 year old with probable eating disorder with altered mental state and weakness

1. Abnormalities:

Primary metabolic alkalosis

compensation: Expected CO2 = 54, actual = 59 –additional respiratory acidosis

Severe hypokalaemia, hypochloraemia

mild hyponatraemia

Low anion gap (not acidosis, just low anion gap)

Normal lactate

2. Differential Diagnosis:

Metabolic alkalosis:

Severe dehydration – vomiting, reduced intake

Possible endocrine abnormality –  Conn’s, Cushing’s

Diuretic abuse

Respiratory acidosis:

compensation plus central cause – drugs, bleed, infection etc

Severe electrolyte depletion – losses from GIT, kidney

Low anion gap without associated acidosis – low albumin is major determinant, also low PO4

3. Treatment Priorities:

Cardiac monitoring

Replace K

ivi fluids, monitor urine output

ICU admission