Diabetes Mellitus

The current criteria for diagnosis include either:

• Fasting blood sugar > 126 (on at least 2 occasions) or
• Random blood sugar > 200 with associated polyuria, polydipsia, and weight loss or
• 2 hour blood sugar > 200

Type I DM or DM1 (previously "Insulin-Dependent DM" or IDDM) is a disorder resulting from a deficiency of insulin secretion, but not in an impaired response to insulin. It tends to be diagnosed in younger patients, although it can occur at any age. It is treated with insulin.

Type II DM or DM2 (previously "Non-Insulin-Dependent DM", or NIDDM) is a disorder resulting from an impaired response to insulin, which is accompanied by an inadequate increase in insulin production. The condition is treated with diet &/or oral medications &/or insulin. Type II DM is by far the more common form. The term NIDDM was dropped because it is often incorrect - many type II diabetics require insulin to stay alive.

Complications result primarily from damage to small vessels and to the nervous system. They include:

• Retinopathy - Fairly common, particularly in Type I, and can lead to blindness. Annual ophthalmologic exam is recommended.
• Peripheral Neuropathy - Loss of touch and vibratory sense are more common than motor defects. Sx tend to start distally, particularly in the lower extremity, and progress proximally. Vigilance in footcare is essential for both patients and providers - patients are often unaware of lesions that can rapidly progress to advanced disease, often requiring amputation.
• Autonomic Neuropathy - Signs include orthostatic hypotension; urinary incontinence, retention, and infection; sexual dysfunction; gastroparesis (hypofunction of GI tract).
• Nephropathy - Microalbuminuria is a common finding, and indicates renal disease. ACE inhibitors are indicated for all diabetics with albuminuria, even those without hypertension.
• Hypertension - Common in diabetics. First pharmacologic intervention should be ACE if albuminuria present. Otherwise, start with thiazides, then beta blockers, then ACE.
• Vasculopathy - Compromises blood flow, particularly to lower extremities, exacerbating potential of foot damage and amputation.
• Coronary Artery Disease - There is strong evidence for diabetes as a primary risk factor for MI or other heart disease.
• Dyslipidemia - Tends to me both more common and more refractory than in other populations.
• DKA (Diabetic Ketoacidosis) - Seen almost exclusively in type I diabetics, results from poor glucose control. S/Sx: Fruity odor to breath, nausea, vomiting, polyuria, polydipsia, confusion, unresponsiveness. Can be fatal. Treatment: IV insulin (10 unit bolus, then 5-10/hour); 3-5 liters isotonic saline, the first 2 pushed - add glucose when serum glucose < 250, add K when needed (preferred: 2/3 KCl, 1/3 K PO4) - K is high at first, but drops dangerously low as glucose corrects - people die from hypokalemia; bicarb only when pH < 7.0.
• HONK (Hyperosmolar Non-Ketotic Coma) - Seen almost exclusively in type II diabetics, results from poor glucose control. S/Sx: Osmotic diuresis (from glucose spilling into urine) leads to severe volume depletion, then stupor, seizures, and coma. Blood glucose > 600. Treatment: IV insulin (10 unit bolus, then 5-10/hour); repletion of fluid deficit, calculated in liters as (0.6 x weight in kg) x ([serum Na+/140] -1). 1/2 of deficit given over 6-8 hours as NS, remaning 1/2 over next 24 hours.

Currently available forms of insulin include:

Enter a weight in either the Kilograms or the Pounds box (just the number, please):
Kilograms:	Pounds:
Please select what type of patient you are working with:
Newly Dx diabetic Long-standing diabetic Sick, or on steroids
If on TPN, enter grams of carbohydrate:
Then:   Or:

When calculating total insulin requirements per day for a newly diagnosed diabetic, calculate as 0.5 units per kilogram body weight. For long-standing diabetics, use 0.6 units/Kg/day. For sick patients or patients on steroids, use 1.0 -1.2 units/Kg/day.	Units of insulin per day
Of this total daily requirement, give 2/3 as NPH and 1/3 as Regular.	Units NPH Units Regular
Of those doses: Give 2/3 of the NPH in the AM and 1/2 of the Regular in the AM. Give the remaining 1/2 of the Regular before the evening meal. Give the remaining 1/3 of the NPH at bedtime.	NPH in AM Regular in AM NPH at dinnertime Units Regular at bedtime
If on 24hr tube feeds, calculate daily insulin as above, but give 70/30 q8hrs instead of other insulins. (1/3 of total requirement at each dose.) Remember to d/c insulin when d/c tube feeds!	Units of 70/30 TID
If on TPN, give one unit Regular in the bag for every 10 grams of carbohydrate. May also need supplemental.	Units of Regular insulin in the bag
Rule of 1500: Divide 1500 by the total units of insulin used daily; the resulting number represents an estimate of the amount the blood sugar will drop with each unit.	mg/dL fingerstick change/unit insulin

If you must give a sliding scale, write to check glucose before each meal and at bedtime, but don’t give as much insulin at bedtime (since patient will not be eating for hours). Make sure to order 1/2 amp D50 or glucose tablets PRN for low fingersticks (<70).

Fingersticks should be QAC (before each meal) and QHS (at bedtime).

If the morning glucose is high, increase evening NPH. If lunch glucose is high, increase morning Regular. If evening stick is high, increase AM NPH. If bedtime stick is high, increase dinnertime Regular.

Using the rule of 1500 (see above), you can calculate supplemental needs. For example, if patient takes 50 units per day, 1500/50=30 - so each unit will drop FS by 30 mg/dl. So, if lunchtime stick is consistently ~ 60 mg/dL high, you can supplement morning Regular with an additional 2 units (or use 2 units Lispro at lunchtime).

For bedtime, never give Lispro - if high (>350) then give Regular based on rule of 1500 (taking into account existing Regular dosage) - be conservative at bedtime!

Complications result primarily from damage to small vessels and to the nervous system. They include:

• Sulfonylureas (Glipizide, Glyburide)- Stimulate beta-cell release of insulin. Can have hypoglycemia as side-effect. DOSE: 2.5-20 mg QD (Glipizide)
• Metformin - Blocks hepatic gluconeogenesis, may enhance glucose uptake in muscle. Do not cause hypoglycemia, but can cause lactic acidosis. Avoid in renal disease, CHF, liver disease, other acidoses. DOSE: 500 mg BID to 850 mg TID
• Acarbose - Blocks carbohydrate digestion. DOSE: 25-100 mg TID
• Troglitazone - Increases muscle glucose uptake (upregulates receptors). Can have hepatic damage as side-effect: Monitor LFT's! DOSE: 200-600 mg QD