What medications should a patient with diabetes, taking dapagliflozin (Forxiga), metformin, perindopril (ACE inhibitor), and gliclazide (sulfonylurea), discontinue prior to undergoing a total abdominal hysterectomy?

Preoperative Medication Management for Total Abdominal Hysterectomy

Stop metformin the night before surgery, discontinue dapagliflozin 3-4 days before surgery, hold gliclazide on the morning of surgery, and consider holding perindopril on the morning of surgery. 1, 2

Dapagliflozin (SGLT2 Inhibitor) - HIGHEST PRIORITY

Discontinue 3-4 days (72-96 hours) before surgery to prevent euglycemic diabetic ketoacidosis (EuDKA), a life-threatening complication that can occur even with normal blood glucose levels. 2

• EuDKA is a serious perioperative risk with SGLT2 inhibitors, characterized by persistent glucosuria and ketonuria that can last up to 11 days after the last dose. 3
• The American Heart Association and American College of Cardiology specifically recommend this 3-4 day discontinuation window for all elective surgeries. 2
• Do not restart dapagliflozin until the patient is clinically stable, eating normally, and has resumed a regular diet postoperatively. 2

Metformin - CRITICAL TO STOP

Stop metformin the night before surgery due to the risk of metformin-associated lactic acidosis (MALA), which carries a 30-50% mortality rate. 1

• Total abdominal hysterectomy is major surgery with risk of hemodynamic instability, tissue hypoperfusion, and acute kidney injury—all factors that increase MALA risk. 4
• The patient is on perindopril (ACE inhibitor), which is specifically identified as a risk factor that can alter renal function and increase lactic acidosis risk. 1
• Do not restart metformin until 48 hours after surgery AND only after confirming adequate renal function (eGFR ≥60 mL/min/1.73m²), normal eating/drinking, and hemodynamic stability. 2, 5, 4

Important Caveat on Metformin Evidence

While one study showed no increased lactic acidosis with continued metformin in cardiac surgery 6, and recent data suggest metformin may not be as strongly associated with lactic acidosis as previously feared 2, consensus guidelines from the American College of Cardiology, American Heart Association, and European societies uniformly recommend discontinuation due to the catastrophic consequences of MALA. 2, 5, 4

Gliclazide (Sulfonylurea)

Hold on the morning of surgery to prevent intraoperative and postoperative hypoglycemia. 1

• Sulfonylureas cause hypoglycemia risk during fasting states, which is particularly problematic during surgery. 1
• If the patient requires emergency surgery and has already taken gliclazide, establish glucose infusion if the patient remains fasting. 1
• Resume gliclazide postoperatively once the patient is eating normally and blood glucose monitoring is established. 1

Perindopril (ACE Inhibitor) - CONSIDER HOLDING

Consider holding perindopril on the morning of surgery, though this is more controversial than the diabetes medications. 7

• ACE inhibitors are identified as medications that can alter renal function perioperatively, particularly when combined with metformin, increasing lactic acidosis risk. 1
• Low-quality evidence suggests withdrawal of ACE inhibitors prior to major surgery may reduce acute kidney injury incidence by approximately 15-50%. 7
• The combination of major abdominal surgery, fasting, potential volume depletion, and ACE inhibitor use creates a "perfect storm" for perioperative renal dysfunction. 1
• If held, restart perindopril postoperatively once the patient is hemodynamically stable and adequately hydrated. 7

Practical Preoperative Timeline

4 days before surgery:

• Stop dapagliflozin (last dose 3-4 days preoperatively) 2

Night before surgery:

• Stop metformin (last dose the evening before) 1, 2, 5

Morning of surgery:

• Hold gliclazide 1
• Consider holding perindopril 7
• Check baseline renal function (eGFR) 2, 5
• Ensure adequate hydration status 5, 4

Postoperative Restart Criteria

Metformin: Wait 48 hours, confirm eGFR ≥60 mL/min/1.73m², patient eating/drinking normally, no hemodynamic instability. 2, 5, 4

Dapagliflozin: Wait until clinically stable, normal diet resumed, no signs of ketosis. 2

Gliclazide: Resume when eating normally with established glucose monitoring. 1

Perindopril: Resume when hemodynamically stable and adequately hydrated. 7