MS3 Review Notes

7/31/2019 MS3 Review Notes

1/11

ADVANCED MEDICAL-SURGICAL MS3

1

Diabetes Mellitus

INSULIN SECRETION AND FUNCTION

1. Insulin is a hormone secreted by the beta cells of the islet of Langerhans in the pancreas.2. Small amounts of insulin are released into the bloodstream in response to changes in blood glucose levels

throughout the day.

3. Increased secretion or a bolus of insulin, released after a meal, helps maintain euglycemia.4. Through an internal feedback mechanism that involves the pancreas and the liver, circulating blood glucose

levels are maintained at a normal range of 60 to 110 mg/dL.

5. Insulin is essential for the utilization of glucose for cellular metabolism as well as for the proper metabolism ofprotein and fat.

a. Carbohydrate metabolisminsulin affects the conversion of glucose into glycogen for storage in the liverand skeletal muscles, and allows for the immediate release and utilization of glucose by the cells.

b. Protein metabolismamino acid conversion occurs in the presence of insulin to replace muscle tissue or toprovide needed glucose (gluconeogenesis).

c. Fat metabolismstorage of fat in adipose tissue and conversion of fatty acids from excess glucose occursonly in the presence of insulin.

6. Glucose can be used in the endothelial and nerve cells without the aid of insulin.7. Without insulin, plasma glucose concentration rises and glycosuria results.

a. Absolute deficits in insulin result from decreased production of endogenous insulin by the beta cell of thepancreas.

b. Relative deficits in insulin are caused by inadequate utilization of insulin by the cell.CLASSIFICATION OF DIABETES

A. Type 1 Diabetes Mellitus

Type 1 diabetes mellitus was formerly known as insulin dependent diabetes mellitus and juvenile diabetes mellitus.

1. Little or no endogenous insulin, requiring injections of insulin to control diabetes and prevent ketoacidosis.2. Five to 10% of all diabetic patients have type 1.3. Etiology: autoimmunity, viral, and certain histocompatibility antigens as well as a genetic component.4. Usual presentation is rapid with classic symptoms of polydipsia, polyphagia, polyuria, and weight loss.5. Most commonly seen in patients under age 30 but can be seen in older adults.B. Type 2 Diabetes Mellitus

Type 2 diabetes mellitus was formerly known as noninsulin dependent diabetes mellitus or adult onset diabetesmellitus.

1. Caused by a combination of insulin resistance and relative insulin deficiencysome individuals havepredominantly insulin resistance, whereas others have predominantly deficient insulin secretion, with little

insulin resistance.

2. Approximately 90% of diabetic patients have type 2.3. Etiology: strong hereditary component, commonly associated with obesity.


2/11


2

4. Usual presentation is slow and typically insidious with symptoms of fatigue, weight gain, poor wound healing,and recurrent infection.

5. Found primarily in adults over age 30; however, may be seen in younger adults and adolescents who areoverweight.

6. Patients with this type of diabetes, but who eventually may be treated with insulin, are still referred to as havingtype 2 diabetes.

DIAGNOSTIC TESTS

LABORATORY TESTS

Laboratory tests include those tests used to make the diagnosis as well as measures to monitor short- andlong-term glucose control.

1. Blood Glucose

Description

Fasting blood sugar (FBS), drawn after at least an 8-hour fast, to evaluate circulating amounts of glucose;postprandial test, drawn usually 2 hours after a well-balanced meal, to evaluate glucose metabolism; and

random glucose, drawn at any time, nonfasting.

Nursing and Patient Care Considerations

1. For fasting glucose, make sure that patient has maintained 8-hour fast overnight; sips of water are allowed.2. Advise patient to refrain from smoking before the glucose sampling because this affects the test results.3. For postprandial test, advise patient that no food should be eaten during the 2-hour interval.4. For random blood glucose, note the time and content of the last meal.5. Interpret blood values as diagnostic for diabetes mellitus as follows:

a. FBS greater than or equal to 126 mg/dL on two occasionsb.

Random blood sugar greater than or equal to 200 mg/dL and presence of classic symptoms of diabetes (polyuria, polydipsia,polyphagia, and weight loss)

6. Fasting blood glucose result of greater than or equal to 100 mg/dL demands close follow-up and repeat monitoring.2. Oral Glucose Tolerance Test

Description

The oral glucose tolerance test (OGTT) evaluates insulin response to glucose loading. FBS is obtained beforethe ingestion of a 50- to 200-g glucose load (usual amount is 75 g), and blood samples are drawn at , 1, 2,

and 3 hours (may be 4- or 5-hour sampling).


1. Advise patient that for accuracy in results, certain instructions must be followed:a. Usual diet and exercise pattern must be followed for 3 days before OGTT.b. During OGTT, the patient must refrain from smoking and remain seated.c. Oral contraceptives, salicylates, diuretics, phenytoin, and nicotinic acid can impair results and may be withheld before testing based

on the advice of the health care provider.

2. Diagnostic for diabetes mellitus if 2-hour value is 200 mg/dL or greater.3. Glycated Hemoglobin (Glycohemoglobin, HbA1c)

Description


3/11


3

Measures glycemic control over a 60- to 120-day period by measuring the irreversible reaction of glucose tohemoglobin through freely permeable erythrocytes during their 120-day lifecycle.


1. No prior preparation, such as fasting or withholding insulin, is necessary.2. Test results can be affected by red blood cell disorders (eg, thalassemia, sickle cell anemia), room temperature, ionic charges, and ambient

blood glucose values.

3. Many methods exist for performing the test, making it necessary to consult the laboratory for normal valuesGENERAL PROCEDURES AND TREATMENT MODALITIES

1. BLOOD GLUCOSE MONITORING

Accurate determination of capillary blood glucose assists patients in the control and daily management of diabetes

mellitus. Blood glucose monitoring helps evaluate effectiveness of medication; reflects glucose excursion after meals;

assesses glucose response to exercise regimen; and assists in the evaluation of episodes of hypoglycemia and

hyperglycemia to determine appropriate treatment

2. INSULIN THERAPY

Insulin therapy involves the subcutaneous injection of immediate-, short-, intermediate-, or long-acting insulin at

various times to achieve the desired effect. Short-acting regular insulin can also be given I.V. About 20 types of insulin

are available in the United States; most of these are human insulin manufactured synthetically. Only about 6% of

diabetics are still using beef or pork insulin due to problems with immunogenicity.

A. Insulin RegimensNPH Only

1. Used alone only in type 2 diabetes when patients are capable of producing some exogenous insulin as asupplement for better glucose control.

2. Traditionally given as a morning dosage to assist with normalization of glucose during the afternoon andevening.

3. Evening or bedtime dosage can be helpful in controlling early-morning hyperglycemia.4. NPH can also be given twice daily (morning and bedtime) to eliminate afternoon hypoglycemia yet provide

nighttime coverage. Typically, 2/3 to of the daily dosage is given before breakfast and 1/3 to is given

at bedtime.

NPH/Regular or NPH/Lispro

1. Short-acting regular insulin or immediate-acting lispro (Humalog) or aspart (Novolog) insulin is added to NPHto promote postprandial glucose control.

2. Short- or immediate-acting insulin added to morning NPH controls glucose elevations after breakfast.3. Increased blood glucose levels after supper can be controlled by the addition of short- or immediate-acting

insulin before supper.

4. NPH and regular, lispro, or aspart insulin given before breakfast and before supper is termed a split-mix regimen, providing 24-hour insulin coverage for type 1 diabetes.

B. Combination Oral Agent and Insulin Therapy1. Appropriate only in type 2 diabetes.


4/11


4

2. Intermediate-acting insulin (NPH) is given in the evening and an oral sulfonylurea agent in themorningcalled BIDS therapy (Bedtime Insulin, Daytime Sulfonylurea).

a. No oral antidiabetic agent is given at bedtime.b. Controlling hepatic glucose production overnight with evening insulin helps to start the day with a lower FBS.c. Daytime antidiabetic agent (usually sulfonylurea), along with diet and exercise, controls daytime blood

glucose levels.

d. Some patients may require regular/NPH insulin injected before supper to assist with elevated postprandialevening glucoses.

3. Combination therapy may also include the use of a thiazolidinedione (pioglitazone [Actos], rosiglitazone[Avandia]), metformin (Glucophage), or other agents.

DIABETES AND RELATED DISORDERS

DIABETES MELLITUS

Diabetes mellitus is a metabolic disorder characterized by hyperglycemia and results from defective insulinproduction, secretion, or utilization.

Pathophysiology and Etiology

1. There is an absolute or relative lack of insulin produced by the beta cell, resulting in hyperglycemia.2. Defects at the cell level, impaired secretory response of insulin to rises in glucose, and increased nocturnal

hepatic glucose production (gluconeogenesis) are seen in type 2 diabetes.

3. Etiology of type 1 diabetes is not well understood; viral, autoimmune, and environmental theories are underreview.

4. Etiology of type 2 diabetes involves heredity, genetics, and obesity.Clinical Manifestations

Onset is abrupt with type 1 and insidious with type

Hyperglycemia

Weight loss, fatigue Polyuria, polydipsia, polyphagia Blurred vision

Altered Tissue Response

Poor wound healing Recurrent infections, particularly of the skin

Diagnostic Evaluation

1. Diabetes can be diagnosed in any of the following ways (and should be confirmed on a different day by any ofthese tests):

a. FBS of greater than or equal to 126 mg/dLb. Random blood glucose of greater than or equal to 200 mg/dL with classic symptoms (polyuria, polydipsia,

polyphagia, weight loss)

c. OGTT greater than or equal to 200 mg/dL on the 2-hour sample


5/11


5

2. Tests for glucose control over time are glycated hemoglobin and fructosamine assay (see pages 911 to 912).These tests are not used for diagnosis.

Management

1. Dieta. Dietary control with caloric restriction of carbohydrates and saturated fats to maintain ideal body weight.

b. The goal of meal planning is to control blood glucose and lipid levels

2. Exercise

Regularly scheduled, moderate exercise performed for at least 30 minutes most days of the week promotesthe utilization of carbohydrates, assists with weight control, enhances the action of insulin, and improves

cardiovascular fitness.

3. Medication

1. Oral antidiabetic agents for patients with type 2 diabetes who do not achieve glucose control with diet and

exercise only.a. Act by a variety of mechanisms, including stimulation of insulin secretion from functioning beta cells, reduction of

hepatic glucose production, enhancement of peripheral sensitivity to insulin, and reduced absorption of

carbohydrates from the intestine.

b. Sulfonylureas and meglitinide analogues may cause hypoglycemic reactions.

c. Biguanides, alpha-glucosidase inhibitors, and meglitinide analogues may cause significant flatus and GI adverse

effects.

Oral Antidiabetic Agents

Second-Generation Sulfonylureas

Glyburide (Micronase, DiaBeta) 1.25-20 mg in single or divided dose with meals Glyburide, micronized (Glynase) 0.75-12 mg in single or divided dose Glipizide (Glucotrol) 2.5-40 mg in single dose or divided dose with meals Glipizide (Glucotrol XL) 5-20 mg in single dose before breakfast Glimepiride (Amaryl)

Biguanides

Metformin (Glucophage) 500-2,550 mg in 2-3 divided doses with meals Metformin (Glucophage XR) 500-2,000 mg daily with evening meal

Alpha-Glucosidase Inhibitors

Acarbose (Precose) 150-300 mg in 3 doses with meals; if < 60 kg, maximum dose 50 mg tid Miglitol (Glyset) 150-300 mg in 3 divided doses with meals

Meglitinide Analogue

Repaglinide (Prandin) 0.5-16 mg in 2-4 divided doses within 30 minutes of starting meal; if meal is skipped,do not take dose

Amino Acid Derivative

Nateglinide (Starlix) 120-360 mg in 3 divided doses within 30 minutes of starting meal; if meal is skipped, donot take dose

Thiazolidinediones


6/11


6

Rosiglitazone (Avandia) 4-8 mg in a single dose or 2 divided doses Pioglitazone (Actos) 15-45 mg in single dose

Combination Agents

Glyburide/metformin (Glucovance) Up to 20/2,000 mg/day in single dose or divided doses Glipizide/metformin (Metaglip) Up to 20/2,000 mg/day in single dose or divided doses Rosiglitazone/metformin (Avandamet) Up to 8/2,000 mg/day in divided doses

2. Insulin therapy for patients with type 1 diabetes who require replacement

a. May also be used for type 2 diabetes when unresponsive to diet, exercise, and oral antidiabetic therapy.

b. Hypoglycemia may result as well as rebound hyperglycemia (Somogyi effect).

c. Commonly results in increased appetite and weight gain.

Insulin Onset, Peak, and Duration

INSULIN ONSET PEAK DURATIONImmediate-acting

(lispro, aspart) 0.25 hour 0.5-1 hour 5 hoursShort-acting

(regular, semilente) 0.5-1 hour 2-4 hours 5-7 hoursIntermediate-acting

(NPH, lente) 1-3 hours 6-12 hours 18-24 hoursLong-acting

(ultralente) 4-6 hours 10-30 hours 24-36 hours(insulin glargine) 1 hour none 24+1 hoursMixed

(Regular 30%, NPH 70%) 0.5 hour 2-12 hours 24 hours(Regular 50%, NPH 50%) 0.5 hour 3-5 hours 24 hours

(Lispro 25%, NPH 75%) 0.25 hour 0.5-1.5 hours 24 hours(Aspart 30%, NPH 70%) 0.25 hour 1-4 hours 24 hours

General Health

Rigid prevention and management guidelines have been established for glycemic control, blood pressure(BP), lipid values, and kidney function to prevent complications. The American Diabetes Association (2003)

recommends the following goals of treatment.

Glycemic control

1. HbA1c < 7%

Preprandial glucose 90 to 130 mg/dL Peak postprandial glucose < 180 mg/dL

2. BP < 130/80 mm Hg

3. Lipid control

Low-density lipoprotein < 100 mg/dL High-density lipoprotein > 40 mg/dL Triglycerides < 150 mg/dL3. Microalbumin (spot urine) < 30 mcg/mg creatinine


7/11


7

Complications

Acute

1. Hypoglycemia occurs as a result of an imbalance in food, activity, and insulin/oral antidiabetic agent.2. Diabetic ketoacidosis (DKA) occurs primarily in type 1 diabetes during times of severe insulin deficiency or illness,

producing severe hyperglycemia, ketonuria, dehydration, and acidosis.3. Hyperosmolar hyperglycemic nonketotic syndrome (HHNKS) affects patients with type 2 diabetes, causing severe

dehydration, hyperglycemia, hyperosmolarity, and stupor.

Chronic

1. Cerebrovascular Disease2. Coronary Artery Disease (CAD)3. Peripheral Vascular Disease4. Retinopathy5. Nephropathy6. Peripheral Neuropathy7. Gastroparesis8. Diarrhea9. Impotence/Sexual Dysfunction10.Orthostatic Hypotension

Nursing Assessment

1. Obtain a history of current problems, family history, and general health history.a. Has the patient experienced polyuria, polydipsia, polyphagia, and any other symptoms?b. Number of years since diagnosis of diabetesc. Family members diagnosed with diabetes, their subsequent treatment, and complications2. Perform a review of systems and physical examination to assess for signs and symptoms of diabetes, general

health of patient, and presence of complications.

a. General: recent weight loss or gain, increased fatigue, tiredness, anxietyb. Skin: skin lesions, infections, dehydration, evidence of poor wound healingc. Eyes: changes in visionfloaters, halos, blurred vision, dry or burning eyes, cataracts, glaucomad. Mouth: gingivitis, periodontal diseasee. Cardiovascular: orthostatic hypotension, cold extremities, weak pedal pulses, leg claudicationf. GI: diarrhea, constipation, early satiety, bloating, increased flatulence, hunger or thirstg. Genitourinary (GU): increased urination, nocturia, impotence, vaginal dischargeh. Neurologic: numbness and tingling of the extremities, decreased pain and temperature perception, changes

in gait and balance

Nursing Diagnoses

Imbalanced Nutrition: More than Body Requirements related to intake in excess of activity expenditures Fear related to insulin injection Risk for Injury (hypoglycemia) related to effects of insulin, inability to eat Activity Intolerance related to poor glucose control


8/11


8

Deficient Knowledge related to use of oral hypoglycemic agents Risk for Impaired Skin Integrity related to decreased sensation and circulation to lower extremities Ineffective Coping related to chronic disease and complex self-care regimen

Nursing Interventions1. Improving Nutrition1. Assess current timing and content of meals.2. Advise patient on the importance of an individualized meal plan in meeting weight-loss goals. Reducing intake of

carbohydrates may benefit some patients; however, fad diets or diet plans that stress one food group and

eliminate another are generally not recommended.

3. Discuss the goals of dietary therapy for the patient. Setting a goal of a 10% (of patient's actual body weight)weight loss over several months is usually achievable and effective in reducing blood sugar and other metabolic

parameters.

4. Assist patient to identify problems that may have an impact on dietary adherence and possible solutions to theseproblems. Emphasize that lifestyle changes should be maintainable for life.

5. Explain the importance of exercise in maintaining/reducing body weight.a. Caloric expenditure for energy in exerciseb. Carryover of enhanced metabolic rate and efficient food utilization6. Assist patient to establish goals for weekly weight loss and incentives to assist in achieving them.7. Strategize with patient to address the potential social pitfalls of weight reduction.2. Teaching About Insulin1. Assist patient to reduce fear of injection by encouraging verbalization of fears regarding insulin injection,

conveying a sense of empathy, and identifying supportive coping techniques.

2. Demonstrate and explain thoroughly the procedure for insulin self-injection (see page 914).3. Help patient to master technique by taking a step-by-step approach.a. Allow patient time to handle insulin and syringe to become familiar with the equipment.b. Teach self-injection first to alleviate fear of pain from injection.c. Instruct patient in filling syringe when he or she expresses confidence in self-injection procedure.4. Review dosage and time of injections in relation to meals, activity, and bedtime based on patient's individualized

insulin regimen.

3. Preventing Injury Secondary to Hypoglycemia1. Closely monitor blood glucose levels to detect hypoglycemia.2. Instruct patient in the importance of accuracy in insulin preparation and meal timing to avoid hypoglycemia.3. Assess patient for the signs and symptoms of hypoglycemia.

a. Adrenergic (early symptoms)sweating, tremor, pallor, tachycardia, palpitations, nervousness from therelease of adrenalin when blood glucose falls rapidly

b. Neurologic (later symptoms)light-headedness, headache, confusion, irritability, slurred speech, lack ofcoordination, staggering gait from depression of central nervous system as glucose level progressively falls

4. Treat hypoglycemia promptly with 15 to 20 g of fast-acting carbohydrates.


9/11


9

a. Half cup (4 oz) juice, 1 cup skim milk, three glucose tablets, four sugar cubes, five to six pieces of hard candy maybe taken orally.

b. Nutrition bar specially designed for diabeticssupplies glucose from sucrose, starch, and protein sources withsome fat to delay gastric emptying and prolong effect; may prevent relapse. Used after hypoglycemia treated

with fact-acting carbohydrate.c. Glucagon 1 mg (subcutaneously or I.M.) is given if the patient cannot ingest a sugar treatment. Family member or

staff must administer injection.

d. I.V. bolus of 50 mL of 50% dextrose solution can be given if the patient fails to respond to glucagon within 15minutes.

5. Encourage patient to carry a portable treatment for hypoglycemia at all times.6. Assess patient for cognitive or physical impairments that may interfere with ability to accurately administer

insulin.

7. Between-meal snacks as well as extra food taken before exercise should be encouraged to preventhypoglycemia.

8. Encourage patients to wear an identification bracelet or card that may assist in prompt treatment in ahypoglycemic emergency.

a. Identification bracelet can be obtained from MedicAlert Foundation International,http://www.medicalert.org.b. Identification card may be requested from the American Diabetes Association,http://www.diabetes.org.STANDARDS OF CARE GUIDELINES

1. Caring for Patients With Diabetes Mellitus2. When caring for patients with diabetes mellitus:3. Assess level of knowledge of disease and ability to care for self4. Assess adherence to diet therapy, monitoring procedures, medication treatment, and exercise regimen5. Assess for signs of hyperglycemia: polyuria, polydipsia, polyphagia, weight loss, fatigue, blurred vision6. Assess for signs of hypoglycemia: sweating, tremor, nervousness, tachycardia, light-headedness, confusion7. Perform thorough skin and extremity assessment for peripheral neuropathy or peripheral vascular disease and

any injury to the feet or lower extremities

8. Assess for trends in blood glucose and other laboratory results9. Make sure that appropriate insulin dosage is given at the right time and in relation to meals and exercise10.Make sure patient has adequate knowledge of diet, exercise, and medication treatment11. Immediately report to health care provider any signs of skin or soft tissue infection (redness, swelling, warmth,

tenderness, drainage)

12.Get help immediately for signs of hypoglycemia that do not respond to usual glucose replacement13.Get help immediately for patient presenting with signs of either ketoacidosis (nausea and vomiting, Kussmaul

respirations, fruity breath odor, hypotension, and altered level of consciousness) or hyperosmolar hyperglycemic

nonketotic syndrome (nausea and vomiting, hypothermia, muscle weakness, seizures, stupor, coma).

4. Improving Activity Tolerance1. Advise patient to assess blood glucose level before and after strenuous exercise.2. Instruct patient to plan exercises on a regular basis each day.
http://www.medicalert.org/http://www.medicalert.org/http://www.medicalert.org/http://www.diabetes.org/http://www.diabetes.org/http://www.diabetes.org/http://www.diabetes.org/http://www.medicalert.org/


10/11


10

3. Encourage patient to eat a carbohydrate snack before exercising to avoid hypoglycemia.4. Advise patient that prolonged strenuous exercise may require increased food at bedtime to avoid nocturnal

hypoglycemia.

5. Instruct patient to avoid exercise whenever blood glucose levels exceed 250 mg/day and urine ketones arepresent. Patient should contact health care provider if levels remain elevated.

6. Counsel patient to inject insulin into the abdominal site on days when arms or legs are exercised.5. Providing Information About Oral Antidiabetic Agents1. Identify barriers to learning, such as visual or hearing impairments, low literacy, distractive environment.2. Encourage active participation of the patient and family in the educational process.3. Teach the action, use, and adverse effects of oral antidiabetic agents.

a. Sulfonylurea compounds promote the increased secretion of insulin by the pancreas and partially normalizeboth receptor and postreceptor defects. Many drug interactions exist, so patient should alert all health care

providers of use. Potential adverse reactions include hypoglycemia, photosensitivity, GI upset, allergic

reaction, reaction to alcohol, cholestatic jaundice, and blood dyscrasias.b. Metformin (Glucophage), a biguanide compound, appears to diminish insulin resistance. It decreases hepatic

glucose production and intestinal reabsorption of glucose and increases insulin reception and glucose

transport in cells. Many drug interactions exist, so patient should alert all health care providers of its use.

Metformin must be used cautiously in renal insufficiency, conditions that may cause dehydration, and

hepatic impairment. Potential adverse reactions include GI disturbances, metallic taste, and lactic acidosis

(rare).

c. Alpha-glucosidase inhibitors (acarbose [Precose] and miglitol [Glyset]) delay the digestion and absorption ofcomplex carbohydrates (including sucrose or table sugar) into simple sugars, such as glucose and fructose,

thereby lowering postprandial and fasting glucose levels.

d. Thiazolidinedione derivatives (rosiglitazone [Avandia] and pioglitazone [Actos]) primarily decrease resistanceto insulin in skeletal muscle and adipose tissue without increasing insulin secretion. Secondarily, they reduce

hepatic glucose production. They should be used cautiously in liver disease and heart failure. Liver function

tests should be monitored periodically. Ovulation may occur in anovulatory premenopausal women. Adverse

reactions include edema, weight gain, anemia, and elevation in serum transaminases.

e. Meglitinide analogues (repaglinide [Prandin]) and amino acid derivatives (nateglinide [Starlix]) stimulatepancreatic release of insulin in response to a meal. They have a more rapid onset and shorter duration than

sulfonylureas. They should not be taken when a meal is skipped or missed. They should be used cautiously in

patients with renal and hepatic dysfunction, and may cause hypoglycemia.

6. Maintaining Skin Integritya. Assess feet and legs for skin temperature, sensation, soft tissue injuries, corns, calluses, dryness, hammer toe or

bunion deformation, hair distribution, pulses, deep tendon reflexes.

7. Improving Coping Strategies1. Discuss with the patient the perceived effect of diabetes on lifestyle, finances, family life, occupation.2. Explore previous coping strategies and skills that have had positive effects.


11/11


11

3. Encourage patient and family participation in diabetes self-care regimen to foster confidence.4. Identify available support groups to assist in lifestyle adaptation.5. Assist family in providing emotional support.

Documents

MS3 Review Notes