How should the insulin dose be adjusted for a patient with type 2 diabetes mellitus and CAD presenting with hyperglycemia on Actrapid and Monotard?

Immediate Insulin Dose Adjustment for Severe Hyperglycemia

For this 70-year-old male with type 2 diabetes and CAD presenting with a blood glucose of 470 mg/dL on 16 units of combined Actrapid and Monotard, immediately increase the total daily insulin dose by approximately 30-40% (adding 5-6 units to the basal component) and add correctional rapid-acting insulin of 8-10 units now to address the acute hyperglycemia. 1

Acute Management of Current Hyperglycemia

• Give 8-10 units of rapid-acting insulin (Actrapid) immediately to address the blood glucose of 470 mg/dL, as this represents severe hyperglycemia requiring urgent correction 1, 2
• Recheck blood glucose in 2-3 hours to assess response and determine if additional correctional insulin is needed 2
• For blood glucose ≥180 mg/dL, the evidence-based approach recommends increasing insulin by 4 units every 3 days during titration, but acute hyperglycemia >400 mg/dL requires immediate intervention 1

Adjusting the Basal Insulin Regimen

• Increase the Monotard (basal insulin) dose from the current regimen to approximately 20-22 units at 7 PM (representing a 30-40% increase from baseline), as the patient's severe hyperglycemia indicates grossly inadequate basal coverage 1, 2
• The current total daily dose of 16 units is likely insufficient for adequate glycemic control, as patients with type 2 diabetes typically require 0.3-0.5 units/kg/day when presenting with severe hyperglycemia 1
• For a 70-year-old patient, assuming average weight of 70-80 kg, the target total daily dose should be approximately 21-40 units/day divided between basal and prandial components 1

Establishing a Proper Insulin Regimen

• Transition to a basal-bolus regimen with 50% of total daily dose as basal insulin and 50% as prandial insulin divided among meals, as blood glucose levels >400 mg/dL indicate need for comprehensive coverage 1, 2
• Start with approximately 10-12 units of basal insulin (Monotard) at bedtime and 4-6 units of rapid-acting insulin (Actrapid) before each main meal 1
• This approach addresses both fasting hyperglycemia (controlled by basal insulin) and postprandial excursions (controlled by prandial insulin) 3, 1

Titration Protocol Moving Forward

• Increase basal insulin by 4 units every 3 days if fasting glucose remains ≥180 mg/dL, or by 2 units every 3 days if fasting glucose is 140-179 mg/dL, until reaching target of 80-130 mg/dL 1, 2
• Adjust prandial insulin doses by 1-2 units or 10-15% every 3 days based on pre-meal and 2-hour postprandial glucose readings 1, 2
• Target fasting plasma glucose of 80-130 mg/dL and postprandial glucose <180 mg/dL 2

Foundation Therapy Considerations

• Ensure the patient is on metformin (if not contraindicated by renal function or other factors), as it remains the foundation of type 2 diabetes therapy even when intensifying insulin 3, 1, 2
• Given the patient's CAD, consider adding or continuing SGLT2 inhibitors for cardiovascular protection if renal function permits 2

Monitoring Requirements

• Check fasting blood glucose daily and pre-meal glucose before each meal to guide ongoing insulin adjustments 2
• Monitor for hypoglycemia, especially as insulin doses are increased, and reduce dose by 10-20% if blood glucose falls below 70 mg/dL without clear cause 1, 2
• Recheck HbA1c in 3 months to assess overall glycemic control 2

Critical Pitfalls to Avoid

• Do not continue with inadequate insulin dosing - blood glucose of 470 mg/dL on only 16 units total daily dose represents severe under-treatment that requires immediate and substantial dose escalation 1, 2
• Do not rely solely on sliding scale insulin - scheduled basal-bolus regimens with fixed prandial doses provide superior glycemic control compared to reactive sliding scale approaches 2
• Do not delay adding prandial insulin when basal insulin alone is insufficient, as evidenced by persistent hyperglycemia throughout the day 1, 2
• Avoid using only correctional insulin without addressing inadequate basal coverage, as this leads to continued poor control 2

Patient Education Essentials

• Teach proper insulin injection technique with 90-degree angle for subcutaneous administration 3, 2
• Instruct on systematic rotation of injection sites within one anatomical area to prevent lipodystrophy 3, 2
• Ensure patient carries 15-20 grams of fast-acting carbohydrate at all times to treat potential hypoglycemia 3, 2
• Educate on recognition and treatment of hypoglycemia, with family members instructed in glucagon use for severe episodes 2