II. Evaluation: Preoperative
- Cardiovascular risk
- See Preoperative Cardiovascular Evaluation
- See Perioperative Cardiovascular Risk
- Preoperative stress testing is often indicated
- Assess for cardiac Autonomic Dysfunction
- Risk of perioperative Hypotension
- Features
- Resting Tachycardia
- Orthostatic Hypotension
- No variation in Heart Rate with respirations
- References
-
Renal Insufficiency (Diabetic Nephropathy)
- Renal Function tests
- Consider 24 Hour Urine Protein and Creatinine
III. Precautions: Fasting
- See Diabetes Sick Day Management
- Fasting is primarily prior to procedures or surgeries
- Patients may also wish to fast for religious reasons
- Break the fast for Hypoglycemia (especially Glucose <70 mg/dl, or symptoms and <80 mg/dl)
- Avoid Fasting in poorly controlled Diabetes Mellitus, pregnancy and acute illness
- Consider using perioperative guidelines below for holding diabetic medications for religious or other fasts
- Medications that rarely cause Hypoglycemia and may typically be continued when Fasting (consider holding for procedures)
- Metformin
- Typically held during perioperative period due to theoretical risk of Lactic Acidosis
- Pioglitazone
- Gliptins or DPP-4 Inhibitors (e.g. Januvia)
- Incretin Mimetic or GLP-1 Analogs (e.g. Victoza)
- Metformin
IV. Management: Perioperative (or Fasting) Blood Sugar control
- Optimize Blood Sugar control prior to surgery
- Monitoring
- Check Blood Glucose every 4 hours prior to surgery and as needed for symptoms of Hypoglycemia
- Perioperative Blood Sugar Monitoring frequency per Anesthesia protocol
- Prefer perioperative mild Hyperglycemia to Hypoglycemia
-
Insulin
- Long acting Insulin (Lantus, Levemir)
- Take full Lantus dose the night before the procedure
- Take 66-80% of the usual morning dose on the day of the procedure
- Take 50% of the usual morning dose if well controlled or Hypoglycemia risk (e.g. elderly, CKD)
- Reduce Tresiba (48 hour duration) dose the day before the procedure
- Intermediate Insulin (NPH Insulin)
- Take full NPH dose the night before the procedure
- Take 66% of the usual morning dose on the day of the procedure
- Mixed-Insulin (e.g. Insulin 70/30)
-
Insulin Pump
-
Insulin Pumps should only deliver basal rate (not bolus)
- Consider Running at 50% of the rate
- Anesthesia can adjust perioperatively
-
Insulin Pumps should only deliver basal rate (not bolus)
- Short-Acting, Rapid-acting or Bolus Insulin (e.g. Lispro, Regular, Aspart, Glulisine)
- Do not take Bolus Insulin (Short-Acting Insulin) on the morning of the procedure
- Long acting Insulin (Lantus, Levemir)
- Consider Variable Rate Insulin Infusion (Insulin Drip) for postoperative Glucose control
- Preferred over use of Sliding Scale Insulin
- Stop Oral Hypoglycemic agents and other diabetic agents before surgery (or Fasting)
- Hold long-acting Sulfonylureas 2-3 days before surgery
- Hold short-acting Sulfonylureas on the night before surgery (or up to 24-36 hours before a 24 hours fast)
- Hold Metformin on day before surgery (risk of Lactic Acidosis)
- Hold Byetta, Symlin on the day of surgery
- Hold Flozins and encourage adequate fluid intake (reduces risk of normoglycemic Ketoacidosis)
- Thiazolidinediones may be continued
- Hold SGLT2 Inhibitor 3 days before surgery and 2 days before procedures (or Fasting if risk of Dehydration)
V. References
- (2021) Presc Lett 28(9): 52
- Dummer (2009) Perioperative Guidelines
- Marks (2003) Am Fam Physician 67:93-100 [PubMed]
