Guidelines for Diabetics

is to maintain the glucose level between 8 and 11 mmol/L (approximately 150 and 200 mg/dL) during surgery to maintain glucose homeostasis and protect against hypoglycemia.

is best for individuals with diabetes mellitus. When multiple patients in the same room, such as an eye room, have diabetes, patients who are more difficult to manage should be scheduled first. For early-morning procedures of short duration where the patient may still be expected to eat according to his or her usual meal plan, it is easiest to give the morning oral medication or insulin and food after the procedure. Shortening the intervals between later meals may compensate for this delay and gradually realign the patient's mealtimes back to the usual schedule. This operative schedule is the easiest for patients and physicians because it has the least disrupting effect on the diabetes regimen and should be advocated by both patient and the physician responsible for managing the diabetes.

is recommended because multiple factors influence blood glucose management. Specific guidelines will not fit every patient's needs. Consider the following criteria when making decisions and recommendations about pre-operative and pre-procedure diabetes medications:

1. Type: Determine whether patient has type 1 or type 2 diabetes mellitus. Many patients are wrongly categorized. Type 1 diabetics should never have all insulin withheld.
2. Age of Onset and Duration: Determine age of onset and duration of diagnosis of diabetes mellitus. Both types 1 & 2 can occur at any age. Long duration (over 10 years with type 2) usually means greater insulin deficiency and/or greater insulin resistance. Type 1 diabetics can become more resistant to insulin and type 2 diabetics can become insulin deficient.
3. Body Habitus: Overweight people (both types) have more insulin resistance and require larger amounts of insulin for control.
4. Medical Regimen: Determine type/amount/frequency of medication(s) being taken.
5. Insulin Therapy: Continuous insulin therapy started within 6 months of diagnosis - usually means severe insulin deficiency or type 1.
6. Co-Morbid Conditions: Document extent of complications to help avoid worsening during procedure, e.g., neuropathic, insensate feet need protection to prevent pressure ulcers; nephropathy means renal blood flow must be protected or patient may be on dialysis; infection may necessitate change in insulin management.
7. Glucose Control: Check blood glucose control, not just random glucose levels - assess recent hemoglobin A1c result and self-monitored glucose log, then check glucose in pre-operative area.
8. Awareness: Does the patient have the ability to recognize symptoms of hypoglycemia and know treatment used for hypoglycemia?
9. Hypoglycemia guidelines include treating blood glucose 80 mg/dl or below with 15 grams glucose (for an average adult: a proportionally smaller dose may be appropriate for a child*), retesting glucose in 15 minutes, and retreating/retesting every 15 minutes until glucose is at least 100 mg/dl.

*Adapting dose for pediatric patient when no per kg or pediatric dose is recommended:

Recommended adult dose mg/kg divided by 70 kg = approximate pediatric dose divided by patient's weight in kg

Therefore:

Approximate pediatric dose mg/kg = (Recommended adult dose mg/kg x child's weight in kg) / (70 kq)

1. Basal Insulin: Always continue basal insulin source (NPH, Lente, Ultralente, glargine (Lantus), insulin pump or intravenous insulin infusion) in order to prevent ketoacidosis. Morbidity and mortality is primarily due to lack of insulin in these patients.
2. Non-Peaking Basal Insulin: Type 1 patients on glargine (Lantus) can be considered to be on a "poor man's pump" which should be continued without diminishing the dose. Glargine is usually taken every 24 hours at night as a basal dose, does not peak, and is dosed unrelated to food intake.
   1. For type 1 patients taking glargine at bedtime, give the usual dose the night before procedure
   2. For type 1 patients taking glargine in the morning, give the usual dose the morning of procedure
3. Peaking Basal Insulins: Dose may need to be adjusted for peaking insulins (NPH, Lente, Ultralente).
   1. Give/have patient take usual dose of NPH insulin the night before procedure
   2. Inpatients should have IV/have outpatients come to hospital and start IV: Give 2/3 usual dose of NPH insulin the morning of procedure; note that piggyback of intravenous dextrose may be needed to decrease risk of hypoglycemia. Post-procedure, test blood glucose and give remainder of usual morning dose of NPH insulin with extra rapid- or short-acting insulin as needed.
   3. For individuals who take long-acting peaking insulin (ie, extended insulin zinc [Ultralente]) and short-acting insulin, a switch to an intermediate-acting type (NPH) a day or two before planned surgery is appropriate.
4. Short Acting Insulin: Omit fast- or rapid-acting (Regular or Humalog) injected insulin the morning of procedure.
5. Continuous Insulin: Patients treated with continuous insulin infusion therapy (insulin pumps) may be treated with their usual basal infusion rate.
6. Complex Patients: Involve patient's endocrinologist or endocrinology consultant for complex or high risk patients.
7. For a long procedure (over 4 hours):consider omitting all subcutaneous insulin and starting intravenous insulin infusion the morning of procedure; use ICU insulin infusion protocol when indicated. Intravenous regular insulin is indicated during the perioperative period for previously insulin-treated patients undergoing long, complex operative procedures; patients who require emergency surgery while in ketoacidosis; and patients with unstable type 1 diabetes.

1. Short-acting insulin: Omit fast- or rapid-acting injected insulin the morning of procedure.
2. NPH insulin: Follow guidelines for type 1 diabetes above.
3. Glargine insulin (Lantus): Type 2 diabetes patients may be prescribed glargine insulin as a basal dose OR may have a larger dose prescribed (sometimes in am and pm divided doses) to compensate in part for meals.
   1. For patients taking glargine at bedtime, give approximately 3/4 the patient's usual dose the night before procedure.
   2. For patients taking glargine in the morning, give approximately 3/4 the patient's usual dose the morning of procedure.
4. For a long procedure (over 4 hours):Consider omitting all subcutaneous insulin and start intravenous insulin infusion the morning of procedure; use ICU insulin infusion protocol when indicated.
5. Oral medications
   1. Omit glucophage XR the evening before procedure or for longer if the patient will be NPO longer or has decreased intake as part of the prep.
   2. Omit glucophage and glucophage XR the morning of procedure.
   3. Alterations in renal function arising intraoperatively during major surgery may potentiate the risk of development of lactic acidosis. In type 2 diabetics, glucophage, the biguanide, should not be resumed for 72 hours postoperatively, when serum creatinine is measured to document the absence of any perfusion or dye-induced renal toxic effects and the return of normal renal function.
   4. Hold sulfonylureas and nonsulfonylurea secretagogues the morning of procedure; they can be restarted when patient can eat usual meals. (Exception: Hold Diabinese (chlorpropamide) 24 hours prior to procedure.)
   5. Thiazolidinediones may be continued if used as monotherapy unless concern exists for fluid retention.
   6. Patients taking 2 or more oral agents should be placed on insulin (regular insulin sliding scale) in the perioperative period.
   7. Hold alpha-glucosidase inhibitors until patient is eating usual meals.
   8. Patients at risk for ischemia should not continue on glibenclamide (glyburide) or metformin perioperatively because there is evidence that these medications prevent cardiac preconditioning.
   9. Other oral diabetes medications should be held until patient is eating usual meals.