Inpatient Diabetes

If you want to avoid the laborious process listed in this chapter, here is a masterpiece of a calculator I coded:

Insulin Calculator

Remember, sliding scales are TERRIBLE

On admission

  • Hold oral agents and place on insulin
  • If already on home insulin, may not need to stop

When on insulin

  • Avoid hypo/hyperglycemia extremes
  • Hypoglycemia- AMS, confusion
  • Hyperglycemia- delayed wound healing, infection risk, longer stay, longer/ delayed procedures


  • Treat when BG's>140s and persistent
  • ICU: goal 140-180
  • Non-ICU goal: premeal (100-140)
  • Random Non-ICU goal: 100-180


  • Lispro: short-acting, used in pre-meal and sliding scales
  • Regular: usually not used
  • NPH: 5-7 hours--> used if you anticipate increase in BGL (steroids)
  • Glargine/Lantus: Basal/long-acting for 24H

Insulin Experienced

  • ICU ill: goal 140-180--> often require insulin drip
  • Not critically ill: BG<140. Do 25-50% of home dose if well-controlled

Insulin naïve

  • Same BG goal as above
  • Determine total daily dose
  • Add sliding scale for pre-meal correction
    • Total daily dose
      • Underweight, old, dialysis: .3U/kg body weight
      • Normal weight: .4U/kg
      • Overweight: .5/kg
      • Obese, insulin resistant, glucocorticoids: >= 0.6U/kg
    • Sliding scale
      • Low dose (underweight, old, CKD):
      • Medium dose (normal weight)
      • High dose: obese, insulin resistant, glucocorticoid use


Example, in case you are confused as I was for years:

47 yo male obese (270kg) with T2DM and A1c is 12, not critically ill. Calculate his insulin dose?

  • TDD: 270kg * 0.6=0.6 162U of insulin
  • Daily basal bolus: 81U basal (long-acting) and 81U bolus (pre-meal)
  • 81U bolus/ 3 meals a day= 27U pre-meal
  • Sliding scale: high dose
  • Final regimen: 81U basal + 27U pre-meal TID + high dose sliding scale for pre-meal correction
  • Daily check of sliding scale to see how you do
    • i.e. 12U of insulin premeal correction needed before each meal= 12 * 3 meals= 36U of insulin
    • Total daily insulin need= 162 U insulin +36=36 198U
      • New regimen= 99U basal + 33U TID
Correctional scale
Glucose RangeInsulin (lispro)