Perioperative Management of Diabetes Mellitus Author: Nadia A. Khan, MD; William A. Ghali, MD; Susan E. Spratt, MD; Melanie E. Mabrey, MSN, ACNP, BC-ADM
Editorial changes - 2012-01-03
Author information and module status
Elements of Risk
Whom and How to Assess
Interventions to Decrease Risk
Patient Education
Follow-up
Tables
Figures
References
Glossary
What's New
Patient Information
Additional Resources
Tools
Interventions to Decrease Risk
  • Plan carefully to optimize glycemic control before surgery.
  • Consider the use of β-blockers perioperatively in selected diabetic patients.
  • Consult with the anesthesiologist to reduce the risk of hypoglycemia and other electrolyte abnormalities.
  • Withhold oral medication the morning of surgery in patients with type 2 diabetes who use oral hypoglycemic agents alone for glycemic control.
  • Adjust insulin dosage before the surgical procedure in patients with type 1 or type 2 diabetes who are treated with insulin with or without oral hypoglycemic agents.
  • Recognize that patients with type 2 diabetes who are treated with diet alone occasionally require drug intervention.
  • Use supplemental short-acting insulin or an intravenous insulin infusion to control intra- or postoperative glucose levels in patients with type 2 diabetes who use only oral hypoglycemic agents as outpatient therapy.
  • Administer subcutaneous correction dose insulin or an intravenous insulin infusion for minor or short surgical procedures in patients with type 1 or type 2 diabetes treated with insulin with or without oral hypoglycemic agents.
  • Use intravenous insulin infusions in patients with type 1 or type 2 diabetes treated with insulin and undergoing major surgical procedures.
  • Control postoperative glucose levels to reduce both cardiac and infectious complications.
  • Continue intraoperative management strategies into the postoperative period if the patient is still not able to eat normally after surgery.
  • Resume the patient's outpatient diabetic diet and treatment regimen once he or she is eating well.

Plan carefully to optimize glycemic control before surgery. C

  • For elective procedures, aim to achieve glycemic goals proposed by the American Diabetes Association and the American Association of Clinical Endocrinologists as recommended for outpatients with diabetes (HbA1C <7%, preprandial glucose <130 mg/dL, and peak postprandial glucose <180 mg/dL), with the caveat being that if the risk of not undergoing surgery outweighs the risk of undergoing surgery with a glucose level slightly above the goal for glycemic control, then proceed with surgery with special attention to improving glycemic control.
  • Recognize that glycemic goals may be less stringent in patients with frequent profound hypoglycemia, elderly or very young patients, or patients with a limited life expectancy.
  • Determine the type of medication used by the patient, including oral hypoglycemic agents and insulin, noting the dosage and frequency of administration.
  • Use details of the patient's current glycemic therapy to plan for perioperative glucose management.
  • Discuss the risks and symptoms of hypoglycemia and cardiac ischemia when discussing other general perioperative risks with the patient before surgery.
  • Encourage patients with diabetes to monitor their own glucose levels the night before and the morning of surgery and to contact a physician if they have low readings (<70 mg/dL or <4.0 mmol/L).
  • Recommend that surgery be scheduled as early in the morning as possible to minimize disruption in their glycemic control.
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Consider the use of β-blockers perioperatively in selected diabetic patients. C

  • If there is no specific contraindication, use a β-blocker perioperatively for patients with at least one major or two minor risk factors for postopereative cardiac complications.
    • A major risk factor is diabetes requiring insulin therapy
    • Minor risk factors are diabetes not requiring insulin therapy, age >=65 years, dyslipidemia, and hypertension
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Consult with the anesthesiologist to reduce the risk of hypoglycemia and other electrolyte abnormalities. C

  • Consult with the anesthesiologist to ensure that:
    • Glucose levels are monitored at least every hour
    • If using insulin during surgery, potassium levels are measured every 4-6 hours during surgery and more frequently if the patient has renal failure or is taking an ACE inhibitor or potassium-sparing diuretics
    • Glucose is measured in the recovery room immediately after surgery
    • Anion gap and serum bicarbonate levels are measured in patients undergoing procedures longer than 6 hours
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Withhold oral medication the morning of surgery in patients with type 2 diabetes who use oral hypoglycemic agents alone for glycemic control. C

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Adjust insulin dosage before the surgical procedure in patients with type 1 or type 2 diabetes who are treated with insulin with or without oral hypoglycemic agents. C

  • Withhold all oral hypoglycemic agents on the morning of surgery.
  • Alter the dosage of insulin depending on the outpatient drug regimen:
    • In patients taking long-acting insulin (e.g., glargine or detemir), give their customary morning and/or evening dose; do not resume pre-meal bolus doses of short- or rapid-acting insulin until patients are eating
    • For patients taking intermediate-acting insulin or mixed intermediate-acting and short- or rapid-acting insulin, either:
      • Administer half of the typical morning dose or
      • Calculate the patient's TDI:
        • Split the TDI into two equal parts of basal insulin (glargine or detemir) and prandial insulin (rapid-acting insulin analogs), the latter of which will be withheld until the patient eats/receives nutrition, or
        • Split the TDI into four equal parts of basal and prandial insulin given as regular insulin every 6 hours, with half of the regular insulin dose given as basal insulin and the other half withheld until the patient eats/receives nutrition; thus, the patient will be given one eighth of the TDI for basal insulin every 6 hours until eating
    • For patients on continuous subcutaneous insulin pumps, discontinue and disconnect the pump, and administer intravenous insulin or a dose of subcutaneous long-acting insulin (glargine or levemir) that equals their 24-hour subcutaneous basal infusion dose through the pump; calculation of the 24-hour basal insulin dose is held in the pump itself and can be accessed by the patient
  • For patients in whom hypoglycemia is a concern while fasting on a typical basal insulin dose, test the home insulin dose 5 to 7 days before surgery by having the patient fast at home, checking fingerstick glucose frequently.
  • Reduce the amount of insulin given if the patient experiences frequent episodes of hypoglycemia in outpatient management.
  • Never withhold basal insulin therapy.
  • See table How to Adjust Insulin While Fasting for a Procedure (Patient Information).
  • See table Calculation of TDI.
  • See table Acceptable Insulin Regimens for Different Inpatient Scenarios.
  • See table Recommendations for Management of Diabetes Medications and Insulin Before Surgery or a Procedure Requiring Fasting.
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Recognize that patients with type 2 diabetes who are treated with diet alone occasionally require drug intervention. B

  • Consider supplemental perioperative short- or rapid-acting insulin, regular or lispro, given subcutaneously every 4 hours on correction dose insulin for blood glucose levels above target.
  • If correction dose insulin is used longer than 24 hours, start scheduled insulin.
  • Recognize that the frequent use of correction dose insulin without scheduled insulin, previously known as “sliding-scale insulin,” is no longer the standard of care.
  • Aim for intraoperative glucose targets between 140 mg/dL and 180 mg/dL.
  • Start intravenous saline infusions at 100 to 150 mL/h for preoperative and intraoperative hydration.
  • Recognize that the use of intravenous insulin may be necessary to achieve tight glycemic control more safely and quickly than subcutaneous insulin.
  • See table Calculation of Correction Dose or Supplemental Insulin Dose.
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Use supplemental short-acting insulin or an intravenous insulin infusion to control intra- or postoperative glucose levels in patients with type 2 diabetes who use only oral hypoglycemic agents as outpatient therapy. B

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Administer subcutaneous correction dose insulin or an intravenous insulin infusion for minor or short surgical procedures in patients with type 1 or type 2 diabetes treated with insulin with or without oral hypoglycemic agents. A

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Use intravenous insulin infusions in patients with type 1 or type 2 diabetes treated with insulin and undergoing major surgical procedures. B

  • In patients with type 1 or type 2 diabetes that is treated with insulin and who are undergoing major surgical procedures that are complex, such as coronary artery bypass surgery, use variable-rate continuous intravenous insulin infusion.
  • Measure blood glucose levels hourly and electrolyte levels every 4 to 6 hours.
  • Give insulin in the morning before surgery as recommended in 3.5.
  • Aim for glucose targets between 100 mg/dL and 139 mg/dL (5.6 mmol/L and 7.7 mmol/L).
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Control postoperative glucose levels to reduce both cardiac and infectious complications. B

  • Maintain postoperative glucose levels (pre-meal and fasting) in the range of 110 to 180 mg/dL in patients undergoing surgical procedures that are not long or complex.
  • Maintain postoperative glucose levels in the range of 100 to 140 mg/dL at pre-meal and fasting times in patients undergoing cardiac surgery.
  • Recognize that intravenous insulin can be the safest way to titrate insulin when trying to obtain intensive glucose targets.
  • Consider more stringent targets in stable patients with previous tight glycemic control or those who are pregnant.
  • Consider less stringent targets for terminally ill patients.
  • Do not use oral diabetes medications for the treatment of inpatient hyperglycemia; insulin is preferred.
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Continue intraoperative management strategies into the postoperative period if the patient is still not able to eat normally after surgery. B

  • If the patient is fasting without caloric intake, continue to provide basal insulin with correction dose insulin if necessary.
  • For patients undergoing more complex procedures on intravenous insulin infusions, continue infusion until the patient is able to eat.
  • Upon resumption of caloric intake, provide the three components of insulin requirements in the hospital:
    • Basal insulin:
      • Continue intravenous insulin (with subcutaneous prandial insulin when eating)
      • Note the subcutaneous insulins used for basal insulin:
        • Glargine every 12 to 24 hours
        • Detemir every 12 hours
        • Regular every 6 hours
        • NPH twice a day
      • Dose subcutaneous basal insulin by extrapolating 24-hour insulin use from the past 12 hours of intravenous insulin use
    • Prandial or nutritional insulin:
      • Administer:
        • Rapid-acting insulin analogs (lispro, aspart, glulisine) before or after a meal, dosed according to how much the patient eats, or
        • Short-acting regular insulin with meals, dosed by doubling the regular insulin dose used for basal insulin
      • Dose prandial insulin by the rule of 500 or by dividing the dose of insulin used for basal insulin by 3 (over 3 meals)
    • Correction dose insulin:
      • Match correction dose insulin to the type of insulin used to cover prandial needs
      • Dose correction dose insulin by using the 5% rule or the rule of 1600
  • Check the dose by calculating the TDI:
    • 0.3 U/kg·d in patients with type 1 diabetes
    • 0.5 to 1.0 U/kg·d in patients with type 2 diabetes
  • Do not stop intravenous insulin until basal insulin has been given for 1 to 3 hours (depending on the type of basal insulin given).
  • Check fingerstick glucose every hour for 3 hours after the first subcutaneous basal insulin injection given; do not wean off of intravenous insulin until the blood glucose level is <150 mg/dL, which will prevent hyperglycemia if an inadequate amount of basal insulin was given.
  • See table Calculation of Correction Dose or Supplemental Insulin Dose.
  • See table Calculation of Prandial Insulin Dose.
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Resume the patient's outpatient diabetic diet and treatment regimen once he or she is eating well. B

  • Consult with the surgical team to ensure that patients with diabetes are given appropriate diabetic diets (i.e., no concentrated sweets, controlled or fixed carbohydrate diet) once they resume oral intake.
  • Guided by the patient's preoperative regimen, resume oral hypoglycemic agents only once the patient is eating normally and has no contraindications to oral or other diabetes therapy.
  • Do not restart metformin if there is renal insufficiency with creatinine clearance <60 mL/min, hypoxia, hypotension, significant hepatic impairment, COPD, or CHF.
  • Be aware that sulfonylureas, meglitinides, and exenatide stimulate insulin secretion and may, therefore, cause hypoglycemia; use these agents only when eating has been well established.
  • Recognize that sulfonylurea therapy is contraindicated in patients with renal insufficiency or renal failure.
  • Consider a step-up approach for those on high-dose sulfonylureas, administering doses at increasing increments until the patient's usual dose is reached.
  • Recognize that exenatide and pramlintide cause significant nausea and may not be appropriate for or tolerated by patients recovering from surgery.
  • Recognize that thiazolidinediones are contraindicated in patients with heart failure, edema, and osteoporosis.
  • Be aware that metformin causes significant nausea, diarrhea, and abdominal bloating and may not be appropriate for or tolerated by patients recovering from surgery; metformin is contraindicated in patients with renal insufficiency, heart failure, and pulmonary disease.
  • Minimize the length of time spent on correction dose insulin if the patient is able to eat.
  • Review glucose levels and insulin doses every 12 to 24 hours, and if correction dose insulin is used frequently, increase the scheduled basal and prandial insulin doses to reflect and anticipate increased insulin needs.
  • Recognize that although some patients with type 2 diabetes may require insulin, many continue to benefit and achieve tighter glycemic control with oral hypoglycemic therapy in addition to insulin if these oral agents are not contraindicated due to the clinical situation.
  • If the patient did not have good glycemic control preoperatively or has had a complication that would preclude using an outpatient regimen, discharge the patient on the inpatient regimen or a modification of the outpatient regimen.
  • Initiate basal insulin in patients with HbA1C levels >8% who have no contraindications to outpatient oral medications.
  • Initiate basal and prandial insulin in patients with HbA1C levels >10% or contraindications to outpatient oral medications.
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FAQs
Melanie E. Mabrey, MSN, ACNP, BC-ADM, is a consultant and speaker for Sanofi-Aventis Pharmaceuticals. Nadia A. Khan, MD has no financial relationships with pharmaceutical companies, biomedical device manufacturers, or health-care related organizations. Susan E. Spratt, MD, is a consultant and speaker for Sanofi Aventis and Novo Nordisk. William A. Ghali, MD has no financial relationships with pharmaceutical companies, biomedical device manufacturers, or health-care related organizations.
Deborah Korenstein, MD, FACP, Co-Editor, PIER, has no financial relationships with pharmaceutical companies, biomedical device manufacturers, or health-care related organizations. Richard B. Lynn, MD, FACP, Co-Editor, PIER, has no financial relationships with pharmaceutical companies, biomedical device manufacturers, or health-care related organizations.

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