Background

Sodium-glucose cotransporter 2 (SGLT2)-inhibitors are increasingly prescribed for heart failure irrespective of diabetes status because of their proven cardiovascular and renal benefits. Although SGLT2-inhibitor-associated euglycaemic ketoacidosis is a recognised complication in patients with diabetes, it remains exceptionally rare in individuals without diabetes, with fewer than 10 cases reported in the literature.

Case presentation

A 78-year-old man with ischaemic cardiomyopathy receiving dapagliflozin 10 mg daily, without a history of diabetes mellitus (HbA1c 5.8%), underwent elective coronary artery bypass grafting. Dapagliflozin was inadvertently continued throughout the perioperative period.

On postoperative day one, he developed a high anion gap metabolic acidosis with marked ketonaemia (blood ketones 5.6 mmol/L), arterial pH 7.24, bicarbonate 17 mmol/L and blood glucose 8.5 mmol/L, consistent with SGLT2-inhibitor-associated euglycaemic ketoacidosis. He was treated with an intravenous insulin infusion alongside 10% dextrose and close biochemical monitoring. Ketonaemia resolved within 24 hours (blood ketones <1.0 mmol/L), metabolic acidosis normalised, and insulin therapy was discontinued. His subsequent recovery was uncomplicated, and he was discharged with plans to recommence dapagliflozin as an outpatient. 

This case demonstrates that perioperative physiological stress may precipitate euglycaemic ketoacidosis in patients without diabetes receiving an SGLT2-inhibitor for heart failure. As the use of SGLT2-inhibitors expands beyond glycaemic management into cardiovascular and renal medicine, clinicians across surgery, anaesthesia, cardiology and internal medicine must recognise that this potentially life-threatening complication can occur even in patients without diabetes.

Conclusion

Perioperative euglycaemic ketoacidosis should be considered in any patient receiving an SGLT2-inhibitor who develops otherwise unexplained metabolic acidosis, irrespective of diabetes status. Careful preoperative medication reconciliation, withholding of SGLT2-inhibitors before major surgery in accordance with current recommendations, and early recognition are essential to minimise morbidity.