Lab Case 29 – Interpretation

17 year old with mixed non anion gap metabolic acidosis and respiratory acidosis and significant ketoacidosis on background of underlying gastritis (likely) and NSAID use for bursitis

pH – moderate to severe acidaemia

HCO3 13, BE – 14 => metabolic acidosis

Anion gap = 13 => non anion gap metabolic acidosis

Compensation: expected CO2 = 27.5, actual = 36, additional respiratory acidosis

Cannot calculate A-a gradient as this is a venous gas

Normal Na, K, glucose and lactate with very high ketones indicating significant vomiting and starvation. Is this patient diabetic?? Euglycaemic diabetic ketoacidosis

Elevated Cl => normal saline therapy as a cause of NAGMA

Other causes include – RTA (NSAID use for bursitis), diuretic abuse (CAI – howvever electrolytes normal, renal function not given)

Respiratory acidosis – aspiration, reduced level of consciousness (opioids for pain, drugs and alcohol), pneumonia

Management of this patient includes fluid rehydration with 5% Dextrose and Insulin infusion to remove ketones. NaHCO3 infusion for suspected RTA, investigation of causes of respiratory acidosis and appropriate treatment.