The case of a 32-year-old woman admitted to Hospital for diabetic coma (GCS 8), with arterial blood pH below usually reported vital range, is described. After First Aid admittance an arterial blood gas analysis adjusted for patient's temperature showed PaO2 10.77 kPa, PaCO2 7.8 kPa, pH 6.52, HCO3 5 mmol/L, BE-34.9. A significant increase of lactate and butyrate concentration was also found. The patient was intubated and breathing was assisted for a 60 hour period after ICU admission, while acidemia was treated by THAM and bicarbonate associated to potassium i.v. infusion (infusions were titrated on acid-base and electrolyte concentration direct monitoring). After progressive neurological and biochemical improvement, 7 days after ICU admission the patient was moved to an Internal Medicine department. This case demonstrated that during diabetic ketoacidosis, despite very low pH (below reported vital range), an invasive intensive treatment could give complete cure without neurological sequelae.