From the Guidelines
For patients who need to hold their GLP-1 receptor agonist before surgery and are not on insulin, metformin is the preferred medication to maintain glycemic control, as it can be continued during the perioperative period to maintain glycemic control 1. When holding GLP-1 receptor agonists for surgery, it is crucial to consider the patient's current medication regimen and glycemic control.
- The patient's usual metformin dose can be continued until the day before surgery, then held 24 hours before the procedure, as recommended for maintaining glycemic control in patients with diabetes or impaired glucose tolerance 1.
- If the patient is not already on metformin, it could be initiated at 500 mg twice daily, with appropriate kidney function monitoring, to help maintain blood glucose levels when GLP-1 therapy is paused.
- For patients who cannot take metformin or need additional glycemic control, a sulfonylurea like glipizide or glimepiride can be considered as a short-term bridge therapy, as they stimulate insulin secretion and can help maintain blood glucose levels. The key concern with holding GLP-1 agonists is potential hyperglycemia, as these medications help regulate blood glucose by enhancing insulin secretion and suppressing glucagon, and close blood glucose monitoring before and after surgery is essential, with target glucose levels typically between 140-180 mg/dL during the perioperative period.
- It is also important to note that SGLT2 inhibitors should be discontinued 3 to 4 days before surgery to reduce the risk of perioperative metabolic acidosis, as recommended in the 2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM guideline for perioperative cardiovascular management for noncardiac surgery 1.
From the Research
Medication Options for Patients Not on Insulin
When holding GLP-1 for surgery, the following medication options can be considered for patients not on insulin:
- Metformin, as it is often the first-line treatment for type 2 diabetes and has a low risk of hypoglycemia 2
- Dipeptidyl peptidase-4 (DPP-4) inhibitors, which prevent the breakdown of GLP-1 and have a low risk of hypoglycemia 2
- Sulfonylureas, although they may have a higher risk of hypoglycemia compared to other options 2
GLP-1 Receptor Agonists
GLP-1 receptor agonists, such as exenatide, liraglutide, albiglutide, dulaglutide, and lixisenatide, can be effective for glycemic control, but their use in the perioperative period is still being studied 3, 2, 4
- These agents may aid patients in meeting the BMI threshold for surgery and improve glycemic control perioperatively 3
- However, complications such as delayed gastric emptying and increased rates of hypoglycemic events have been reported 3
Fixed-Ratio Combinations
Fixed-ratio combinations of insulin-GLP-1 receptor agonist, such as iGlarLixi and IDegLira, may be an option for treatment intensification, but their use in patients not on insulin is not well established 5
- These combinations have been shown to have excellent glucose-lowering efficacy, a lower risk of hypoglycemia, and a neutral effect on body weight 5