What dose of insulin (regular insulin) should be administered to a patient with hyperglycemia to lower their blood glucose from 371 mg/dl to approximately 180 mg/dl?

Management of Hyperglycemia with Blood Glucose of 371 mg/dL

For a patient with a blood glucose of 371 mg/dL, administer a regular insulin dose of approximately 10-13 units to reduce glucose to approximately 180 mg/dL, following a basal-bolus insulin regimen for ongoing management.

Calculating the Appropriate Insulin Dose

When managing severe hyperglycemia (blood glucose >300 mg/dL), a systematic approach is needed:

1. Initial insulin dose calculation:

   • For blood glucose >300 mg/dL, a basal-bolus regimen is recommended 1
   • The formula to calculate insulin dose is based on the "rule of 1800" where:
     • Insulin sensitivity factor = 1800 ÷ total daily insulin dose
     • For an average adult, starting with 0.3 units/kg/day as total daily dose 1
     • For a 70kg adult: 0.3 × 70 = 21 units total daily dose
     • Insulin sensitivity factor = 1800 ÷ 21 = approximately 85
     • To lower glucose from 371 mg/dL to 180 mg/dL: (371-180) ÷ 85 = approximately 2.2 units

2. Correction factor adjustment:

   • For severe hyperglycemia (>300 mg/dL), the standard correction factor may be insufficient
   • A more aggressive approach is needed with approximately 0.1 unit/kg as bolus 1
   • For a 70kg adult: 0.1 × 70 = 7 units

3. Combined approach:

   • Total insulin dose needed: 7-10 units of regular insulin
   • This may need to be adjusted based on insulin sensitivity

Implementation Protocol

For immediate management:

1. Administer regular insulin:

   • Give 10-13 units of regular insulin subcutaneously
   • Monitor blood glucose every 1-2 hours until stabilized

2. Establish ongoing insulin regimen:

   • For continued management, implement a basal-bolus regimen 1
   • Total daily dose: 0.3 units/kg/day (for severe hyperglycemia)
   • Half as basal insulin, half as bolus insulin divided between meals

3. Monitor for response:

   • Target blood glucose range: 140-180 mg/dL 1
   • If glucose does not fall by at least 50 mg/dL in the first hour after administration, consider doubling the correction dose 1

Important Considerations and Pitfalls

• Avoid sliding scale insulin alone: Using sliding scale insulin by itself is associated with poorer glycemic control (20 mg/dL higher mean glucose) 2

• Risk of hypoglycemia: Be vigilant for hypoglycemia, especially when administering larger insulin doses. Have glucose monitoring and treatment protocols ready 1

• Timing considerations: Regular insulin has a peak effect at 2-4 hours, so monitor accordingly to prevent overshooting target and causing hypoglycemia

• Underlying causes: While treating the hyperglycemia, investigate potential causes such as infection, medication effects, or poor baseline control

• Transition plan: Once blood glucose is stabilized, transition to an appropriate maintenance regimen based on the patient's usual diabetes management 1

By following this approach, you should be able to safely reduce the patient's blood glucose from 371 mg/dL to approximately 180 mg/dL while minimizing risks of complications.