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Diabetes Medication Fasting — FRCA Final MCQ

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EasyPreoperative AssessmentDiabetes Medication FastingFRCA Final

A 72-year-old man with type 2 diabetes takes gliclazide 80 mg twice daily and metformin 1 g twice daily. He is scheduled for an afternoon elective hernia repair and is expected to miss only lunch. His eGFR is 70 mL/min/1.73 m², no iodinated contrast will be used, and his capillary blood glucose at 07:00 is 8.2 mmol/L. Under current UK perioperative diabetes guidance, which is the most appropriate medication plan for the day of surgery?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Omit gliclazide and continue metformin as usual

Explanation lettering: E = shown as B · B = shown as C · C = shown as E

The correct answer is C. Gliclazide is a sulfonylurea that stimulates insulin secretion independently of food intake, so it risks hypoglycaemia during fasting; the CPOC/JBDS medication tables direct that sulfonylurea doses are omitted on the day of surgery for an afternoon list and not restarted until the patient is eating. Metformin taken once or twice daily is continued as normal because his eGFR exceeds 60 mL/min/1.73 m² and no iodinated contrast is planned, so lactic acidosis risk is not increased. Options A and B (full or half gliclazide dose) leave an avoidable hypoglycaemia risk. Option D needlessly omits metformin, worsening perioperative glycaemic control. Option E is excessive: a variable-rate intravenous insulin infusion is reserved for patients missing more than one meal or with persistently elevated glucose, whereas this man will miss a single meal and has a satisfactory glucose of 8.2 mmol/L.

Reference: Centre for Perioperative Care (CPOC), Guideline for Perioperative Care for People with Diabetes Mellitus Undergoing Elective and Emergency Surgery – Quick Reference Guide, medication adjustment table, 2021. https://www.mkuh.nhs.uk/wp-content/uploads/2022/07/CPOC-Guideline-for-Perioperative-Care-for-People-with-Diabetes-Mellitus-Undergoing-Elective-and-Emergency-Surgery-Quick-Reference-Guide.pdf