Perioperative medication management

Metformin

1. Before Surgery:
   • Stop Metformin: Generally advised to stop metformin 24-48 hours before surgery to reduce the risk of lactic acidosis, especially if using general anesthesia or having contrast studies.
   • Monitor Blood Glucose: Ensure blood glucose levels are monitored closely. Adjustments may be needed with alternative diabetes management strategies.
2. After Surgery:
   • Resume Metformin: Typically, metformin can be resumed 48 hours post-surgery, once normal renal function is confirmed.
   • Hydration: Maintain adequate hydration to help prevent lactic acidosis.

Anticoagulants and Antiplatelets

1. Before Surgery:
   • Warfarin/Coumadin: Usually stopped 5 days before surgery, replaced with a shorter-acting anticoagulant like heparin if necessary.
   • DOACs (e.g., Rivaroxaban, Apixaban): Often stopped 2-3 days before surgery, depending on renal function.
   • Aspirin and Clopidogrel: Depending on the surgery, these may be stopped 5-7 days prior to reduce bleeding risk.
   • If very high risk complication or recent stroke/ VTE – may need to consider heparin infusion management in the hospital
2. After Surgery:
   • Resume as Advised: Blood thinners are typically restarted post-operatively based on the risk of bleeding and thromboembolism, often within 24-48 hours.
   • Monitor: Regular monitoring of blood coagulation levels may be necessary.

Insulin

1. Before Surgery:
   • Adjust Dose: The dose of insulin may need to be adjusted. Long-acting insulins might be reduced by 50% the evening before surgery.
   • Short-acting Insulin: May be withheld on the morning of surgery; blood glucose levels will be monitored and managed perioperatively.
2. Day of Surgery:
   • Fasting: Patients should fast from midnight before surgery. Regular blood glucose monitoring and appropriate insulin adjustments are critical.
3. After Surgery:
   • Resume Insulin: Insulin therapy is resumed based on blood glucose levels and dietary intake.
   • Monitor Glucose: Frequent blood glucose checks will guide insulin dosing to maintain target glucose levels.

Other Considerations

1. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs):
   • Usually stopped 1-2 days before surgery to reduce the risk of bleeding.
2. Steroids:
   • If on long-term steroids, a stress dose may be required during surgery. Do not stop abruptly.
3. Herbal Supplements:
   • Many herbal supplements (e.g., ginkgo biloba, garlic, ginseng) should be stopped 1-2 weeks before surgery due to potential bleeding risks or interactions with anesthesia.
4. Blood Pressure Medications:
   • Generally continued, but consult your healthcare provider for specific advice, especially for ACE inhibitors and ARBs.