What are the recommendations for insulin therapy in a patient with Type 2 Diabetes Mellitus (T2DM) and hyperglycemia post-prostatectomy?

Insulin Management for Post-Prostatectomy T2DM Patient with Glucose of 170 mg/dL

For a post-prostatectomy patient with Type 2 Diabetes Mellitus (T2DM) and a blood glucose of 170 mg/dL, a basal-bolus insulin regimen should be initiated with close monitoring of blood glucose levels to maintain target glucose below 180 mg/dL (10 mmol/L). 1

Initial Insulin Management

• Maintain intravenous insulin infusion (if currently in place) until blood glucose levels are stable below 180 mg/dL (10 mmol/L) 1
• Transition to subcutaneous insulin when oral feeding resumes, using a basal-bolus regimen 1
• Calculate initial insulin doses based on the following formula:
  • Total daily insulin requirement: 0.3-0.4 units/kg/day 1
  • If transitioning from IV insulin: Use half of the total 24-hour IV insulin dose as basal insulin, and divide the other half into three doses for mealtime bolus insulin 1

Basal-Bolus Regimen Implementation

• Administer long-acting basal insulin (intermediate-acting human insulin or long-acting insulin analog) once daily, preferably in the evening around 20:00 hrs 1
• Provide rapid-acting insulin analogs before meals, with doses adjusted according to carbohydrate intake 1
• When transitioning from IV insulin to subcutaneous insulin:
  • Give the first basal insulin dose immediately after stopping the IV infusion 1
  • Administer the first bolus insulin dose at the first meal 1

Blood Glucose Monitoring

• Monitor blood glucose levels regularly (at least 4 times daily) during the post-operative period 1
• Use fasting plasma glucose values to titrate basal insulin 2
• Use both fasting and postprandial glucose values to adjust mealtime insulin doses 2
• Target blood glucose levels below 180 mg/dL (10 mmol/L) to reduce risk of surgical site infections and other postoperative complications 1

Management of Hypo/Hyperglycemia

• For hypoglycemia (blood glucose <60 mg/dL or 3.3 mmol/L):

  • Administer glucose immediately, even without clinical symptoms 1
  • Use oral glucose if patient is conscious; IV glucose if unconscious 1

• For hyperglycemia (blood glucose >300 mg/dL or 16.5 mmol/L):

  • Check for ketosis in insulin-treated patients 1
  • Administer additional rapid-acting insulin and ensure adequate hydration 1
  • If ketosis is present, suspect ketoacidosis and consider ICU transfer 1

Continuation of Treatment

• Continue metformin alongside insulin therapy if previously prescribed and not contraindicated, as this combination decreases weight gain, lowers insulin dose requirements, and reduces hypoglycemia risk 2
• Consider gradually reintroducing other oral antidiabetic medications as the patient recovers, but do not abruptly discontinue them when starting insulin 2
• Adjust insulin doses based on daily blood glucose monitoring results 1, 2

Common Pitfalls and Considerations

• Avoid intramuscular injections, especially with long-acting insulins, as severe hypoglycemia may result 2
• Use the shortest needles available (4-mm pen or 6-mm syringe needles) to minimize pain and avoid intramuscular injection 2
• Be aware that surgical stress can increase insulin resistance temporarily, requiring higher insulin doses initially with potential need for reduction as the patient recovers 1
• Monitor for lipohypertrophy (insulin-induced fat deposits) and rotate injection sites to prevent poor insulin absorption 2
• Recognize that steroids commonly used perioperatively can significantly increase insulin requirements, requiring dose adjustments as steroids are tapered 1