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QUICK REFERENCE GUIDE TO DIABETES FOR HEALTH CARE PROVIDERS

Chapter 7
Insulin and Type 1 Diabetes

Some insulin must be available at all times for persons with type 1 diabetes. Insulin doses may be reduced but usually should never be completely eliminated; to do so can be life threatening.

Starting Insulin Doses

Additional Information:

• Generally 0.5-1 unit per kg. of body wt. (adolescents often need closer to 1 unit per kg.)
• Insulin dose should mimic the normal physiologic insulin secretion and take into account the persons lifestyle.
• Long-acting insulin and insulin analogs can be used to provide basal insulin needs, coupled with rapid or short-acting insulin to cover food intake and for correction of hyperglycemia.
• Total Daily Dose:
  ~50-65% is basal
  ~35-50% is bolus (meal coverage)
• Infants and small children may only need NPH in the AM and evening or may need insulin diluted.

Pre-dinner NPH can be delayed until bedtime to prevent nocturnal hypoglycemia or counteract the "Dawn Phenomenon". A "honeymoon phase" may occur within a few weeks after diagnosis and last for several months to 2 years. During this time, insulin needs are reduced to about 0.1-0.3 units per kg and only one injection per day may be required. Insulin should be reduced when child leaves the pubertal phase, otherwise obesity and unexplained hypoglycemia can result.

Activity

Adjustments in food intake or insulin dose are often needed for activity (see Chapter 4 Physical Activity and Diabetes)

Adjustment of Insulin (Twice - Daily Insulin Regimens)

Problems should occur 3 days in a row before changes are initiated.

• Fasting hyperglycemia: Check 3 AM blood glucose. If it is >70 mg/dl,
  • Increase evening NPH by 10% or
  • Changing NPH dose from pre-supper to pre-bed (may lower risk of nocturnal hypoglycemia and eliminate the need for a bedtime snack)
• Fasting hypoglycemia (and low 3 AM blood glucose): Reduce evening NPH by 15%, and possibly move NPH to bedtime if 3 AM is still low.
• Elevated midmorning or pre-lunch blood glucose: Increase AM rapid-acting insulin by 10%.
• Pre-lunch blood glucose <70 mg/dl: If using short-acting insulin, change to rapid-acting. If still low, reduce AM rapid-acting insulin by 15%.
• Pre-supper blood glucose higher than desired: Increase AM NPH by 10%.
• Elevated evening blood glucose (>180 mg/dl after supper and pre-bed over 120 mg/dl after bedtime snack for 3 days): Increase pre-supper Rapid insulin by 10%.

Also, make certain that the insulin injection is given 30 minutes before meal if using short-acting insulin. Rapid-acting insulin can be given at the time of eating typically 15 minutes before eating. Rapid-acting insulin can also be given after the meal if the amount of consumption cannot be predicted (e.g. picky eaters). It may also be useful to check technique and injection sites used. The exact amount of change needed will vary from person to person.

Intensive Therapy
Research shows that keeping blood glucose levels as close to normal as possible resulted in the development of significantly fewer complications. Intensive therapy generally involves making adjustments in insulin doses (via multiple insulin injections or use of an insulin pump) to accommodate activity, food intake and pre and post-meal blood glucose levels. However, it can be risky for extremely young children and infants because of the risk of permanent damage from hypoglycemic events. See Chapter 8 for sample insulin regimens.

References: American Diabetes Association (2006). Clinical Practice Recommendations. Diabetes Care, Vol 29 (1).