Abdominal Pain and Fruity Breath Odour

🗒️ Question

A 25 year old woman with type 1 diabetes presents to the Emergency Department with abdominal pain, vomiting, and confusion. She has missed several doses of insulin due to illness.

On examination, she appears drowsy and dehydrated. Her pulse rate is 112 bpm, blood pressure is 85/55 mmHg, respiratory rate is 30 breaths per minute, and oxygen saturation is 96% on room air. Her breath has a fruity odour.

Investigations:

• Blood capillary glucose: 31 mmol/L (4.0–7.8)

• Blood capillary ketones: 6.5 mmol/L (<0.6)

• Venous pH: 7.12 (7.35–7.45)

Which investigation is most appropriate to confirm the diagnosis?

(A) Arterial blood gas analysis

(B) Serum bicarbonate

(C) Plasma osmolality

(D) Urine ketones

(E) Venous blood gas analysis