Diabetes Mellitus

  1. General information
    1. Diabetes mellitus represents a heterogenous group of chronic disorders characterized by hyperglycemia.
    2. Hyperglycemia is due to total or partial insulin deficiency or insensitivity of the cells to insulin.
    3. Characterized by disorders in the metabolism of carbohydrate, fat, and protein, as well as changes in the structure and function of blood vessels.
    4. Most common endocrine problem; affects over 11 million people in the U.S.
    5. Exact etiology unknown; causative factors may include
      1. genetics, viruses, and/or autoimmune response in type I
      2. genetics and obesity in type II
    6. Types
      1. Type I (insulin-dependent diabetes mellitus [IDDM])
        1. secondary to destruction of beta cells in the islets of Langerhans in the pancreas resulting in little or no insulin production; requires insulin injections.
        2. usually occurs in children or in nonobese adults.
      2. Type II (non-insulin-dependent diabetes mellitus [NIDDM])
        1. may result from a partial deficiency of insulin production and/or an insensitivity of the cells to insulin.
        2. usually occurs in obese adults over 40.
      3. Diabetes associated with other conditions or syndromes, e.g., pancreatic disease, Cushing's syndrome, use of certain drugs (steroids, thiazide diuretics, oral contraceptives).
    7. Pathophysiology
      1. Lack of insulin causes hyperglycemia (insulin is necessary for the transport of glucose across the cell membrane).
      2. Hyperglycemia leads to osmotic diuresis as large amounts of glucose pass through the kidney; results in polyuria and glycosuria.
      3. Diuresis leads to cellular dehydration and fluid and electrolyte depletion causing polydipsia (excessive thirst).
      4. Polyphagia (hunger and increased appetite) results from cellular starvation.
      5. The body turns to fats and protein for energy; but in the absence of glucose in the cell, fats cannot be completely metabolized and ketones (intermediate products of fat metabolism) are produced.
      6. This leads to ketonemia, ketonuria (contributes to osmotic diuresis), and metabolic acidosis (ketones are acid bodies).
      7. Ketones act as CNS depressants and can cause coma.
      8. Excess loss of fluids and electrolytes leads to hypovolemia, hypotension, renal failure, and decreased blood flow to the brain resulting in coma and death unless treated.
    8. Acute complications of diabetes include diabetic ketoacidosis, insulin reaction, hyperglycemic hyperosmolar nonketotic coma.
  2. Medical management
    1. Type I: insulin, diet, exercise
    2. Type II: ideally managed by diet and exercise; may need oral hypoglycemics or occasionally insulin if diet and exercise are not effective in controlling hyperglycemia; insulin needed for acute stresses, e.g., surgery, infection
    3. Diet (see Exchange Lists, Appendix)
      1. Type I: consistency is imperative to avoid hypoglycemia
      2. Type II: weight loss is important since it decreases insulin resistance
      3. High fiber, low fat diet also recommended
    4. Drug therapy
      1. Insulin: used for Type I diabetes (also occasionally used in Type II diabetes)
        1. types (Table 4.23)
          1. short acting: used in treating ketoacidosis; during surgery, infection, trauma; management of poorly controlled diabetes; to supplement longer-acting insulins
          2. intermediate: used for maintenance therapy
          3. long acting: used for maintenance therapy in clients who experience hyperglycemia during the night with intermediate-acting insulin
        2. various preparations of short-, intermediate-, and long-acting insulins are available (see Table 4.23)
        3. insulin preparations can consist of a mixture of beef and pork insulin, pure beef, pure pork, or human insulin. Human insulin is the purest insulin and has the lowest antigenic effect.
        4. human insulin is recommended for all newly diagnosed Type I diabetics, Type II diabetics who need short-term insulin therapy, the pregnant client, and diabetic clients with insulin allergy or severe insulin resistance.
        5. insulin pumps are small, externally worn devices that closely mimic normal pancreatic functioning. Insulin pumps contain a 3 ml syringe attached to a long (42 inch), narrow-lumen tube with a needle or Teflon catheter at the end. The needle or Teflon catheter is inserted into the subcutaneous tissue (usually on the abdomen) and secured with tape or a transparent dressing. The needle or catheter is changed at least every 3 days. The pump is worn either on a belt or in a pocket (see Figure 4.21). The pump uses only regular insulin. Insulin can be administered via the basal rate (usually 0.5-2.0 units/hr) and by a bolus dose (which is activated by a series of button pushes) prior to each meal.
      2. Oral hypoglycemic agents (Table 4.24)
        1. used for Type II diabetics who are not controlled by diet and exercise
        2. increase the ability of islet cells of the pancreas to secrete insulin; may have some effect on cell receptors to decrease resistance to insulin
    5. Exercise: helpful adjunct to therapy as exercise decreases the body's need for insulin.
  3. Assessment findings
    1. All types: polyuria, polydipsia, polyphagia, fatigue, blurred vision, susceptibility to infection
    2. Type I: anorexia, nausea, vomiting, weight loss
    3. Type II: obesity; frequently no other symptoms
    4. Diagnostic tests
      1. Fasting blood sugar
        1. a level of 140 mg/dl or greater on at least two occasions confirms diabetes mellitus
        2. may be normal in Type II diabetes
      2. Postprandial blood sugar: elevated
      3. Oral glucose tolerance test (most sensitive test): elevated
      4. Glycosolated hemoglobin (hemoglobin A1c) elevated
  4. Nursing interventions
    1. Administer insulin or oral hypoglycemic agents as ordered; monitor for hypoglycemia, especially during period of drug's peak action.
    2. Provide special diet as ordered.
      1. Ensure that the client is eating all meals.
      2. If all food is not ingested, provide appropriate substitutes according to the exchange lists or give measured amount of orange juice to substitute for leftover food; provide snack later in the day.
    3. Monitor urine sugar and acetone (freshly voided specimen).
    4. Perform finger sticks to monitor blood glucose levels as ordered (more accurate than urine tests).
    5. Observe for signs of hypo/hyperglycemia.
    6. Provide meticulous skin care and prevent injury.
    7. Maintain I&O; weigh daily.
    8. Provide emotional support; assist client in adapting to change in life-style and body image.
    9. Observe for chronic complications and plan care accordingly.
      1. Atherosclerosis: leads to coronary artery disease, MI, CVA, and peripheral vascular disease.
      2. Microangiopathy: most commonly affects eyes and kidneys.
      3. Kidney disease
        1. recurrent pyelonephritis
        2. diabetic nephropathy
      4. Ocular disorders
        1. premature cataracts
        2. diabetic retinopathy
      5. Peripheral neuropathy
        1. affects peripheral and autonomic nervous systems
        2. causes diarrhea, constipation, neurogenic bladder, impotence, decreased sweating
    10. Provide client teaching and discharge planning concerning
      1. Disease process
      2. Diet
        1. client should be able to plan meals using exchange lists before discharge
        2. emphasize importance of regularity of meals; never skip meals
      3. Insulin
        1. how to draw up into syringe
          1. use insulin at room temperature.
          2. gently roll vial between palms of hands.
          3. draw up insulin using sterile technique.
          4. if mixing insulins, draw up clear insulin before cloudy insulin.
        2. injection technique
          1. systematically rotate sites to prevent lipodystrophy (hypertrophy or atrophy of tissue).
          2. insert needle at a 45° or 90° angle depending on amount of adipose tissue.
        3. may store current vial of insulin at room temperature; refrigerate extra supplies.
        4. provide many opportunities for return demonstration.
      4. Oral hypoglycemic agents
        1. stress importance of taking the drug regularly.
        2. avoid alcohol intake while on medication.
      5. Urine testing (not very accurate reflection of blood glucose level)
        1. May be satisfactory for Type II diabetics since they are more stable.
        2. Use Clinitest, Tes-tape, Diastix for glucose testing.
        3. Perform tests before meals and at bedtime.
        4. Use freshly voided specimen.
        5. Be consistent in brand of urine test used.
        6. Report results in percentages.
        7. Report results to physician if results are greater than 1%, especially if experiencing symptoms of hyperglycemia.
        8. Urine testing for ketones should be done by Type I diabetic clients when there is persistent glycosuria, increased blood glucose levels, or if the client is not feeling well (Acetest, Ketostix).
      6. Blood glucose monitoring
        1. Use for Type I diabetic clients since it gives exact blood glucose level and also detects hypoglycemia.
        2. Instruct client in finger-stick technique, use of monitor device (if used), and recording and utilization of test results.
      7. General care
        1. perform good oral hygiene and have regular dental exams.
        2. have regular eye exams.
        3. care for "sick days" (e.g., cold or flu)
          1. do not omit insulin or oral hypoglycemic agents since infection causes increased blood sugar.
          2. notify physician.
          3. monitor urine or blood glucose levels and urine ketones frequently.
          4. if nausea and/or vomiting occurs, sip on clear liquids with simple sugars.
      8. Foot care
        1. wash feet with mild soap and water and pat dry.
        2. apply lanolin to feet to prevent drying and cracking.
        3. cut toenails straight across.
        4. avoid constricting garments such as garters.
        5. wear clean, absorbent socks (cotton or wool).
        6. purchase properly fitting shoes and break new shoes in gradually.
        7. never go barefoot.
        8. inspect feet daily and notify physician if cuts, blisters, or breaks in skin occur.
      9. Exercise
        1. undertake regular exercise; avoid sporadic, vigorous exercise.
        2. food intake may need to be increased before exercising.
        3. exercise is best performed after meals when the blood sugar is rising.
      10. Complications
        1. learn to recognize signs and symptoms of hypo/hyperglycemia.
        2. eat candy or drink orange juice with sugar added for insulin reaction (hypoglycemia).
      11. Need to wear a Medic-Alert bracelet.

TABLE 4.23 Characteristics of Insulin Preparations

Action in Hours







Compatible Mixed with

Rapid acting

Insulin injection

Regular insulin





All insulin preparations except lente

Insulin, zinc suspension, prompt

Semilente insulin





Lente preparations

Intermediate acting

Isophane insulin injection

NPH insulin





Regular insulin injection

Insulin zinc suspension

Lente insulin


1-1 1/2



Regular insulin and Semilente preparations

Long acting

Insulin zinc suspension, extended

Ultralente insulin





Regular insulin and Semilente preparations

FIGURE 4.21 Insulin infusion pump

TABLE 4.24 Oral Hypoglycemic Agents


Onset of Action (hrs)

Peak Action (hrs)

Duration of Action (hrs)


Oral Sulfonylureas

Acetohexamide (Dymelor)




Chlorpropamide (Diabinase)




Glyburide (Micronase, Diabeta)

15 min-1 hr



Oral Biguanides

Metformin (Glucophage)



Decreases glucose production in liver; decreases intestinal absorption of glucose and improves insulin sensitivity

Oral Alpha-glucosidose Inhibitor

Acarbose (Precose)




Delay glucose absorption and digestion of carbohydrates, lowering blood sugar.

Miglitol (Glyset)


Troglitazone (Rezulin)




Reduces plasma glucose and insulin. Exact mechanism is unknown. Potentiates action of insulin in skeletal muscle and decreases glucose production in liver.