A 19 year old pregnant insulin dependent diabetic patient was admitted with a history of polyuria and thirst. She now felt ill and presented to hospital. There was a history of poor compliance with medical therapy. She was afebrile. Chest was clear. Circulation was adequate. Perioral herpes was present. Urinalysis: 2+ ketones, 4+ glucose. Biochemistry on admission: Na+ 136, K+ 4.8, Cl- 101, 'total CO2' 10, glucose 19.0, urea 8.1 and creatinine 0.09 (all biochem results in mmol/l). Arterial blood gases were collected on arrival:
pH: 7.26 pCO2: 16 mmHg pO2: 128 mmHg HCO3: 7.1 mmol/l
What is the most likely diagnosis?
A) non-ketotic hyperosmolar coma
B) Severe hypoglycemia
C) Diabetic ketoacidosis
E) Pulmonary embolism