ch 48 DM Flashcards
is the leading cause of adult blindness, end-stage renal disease, and nontraumatic lower limb amputations. It is a major contributing factor to heart disease and stroke.
Diabetes
, singly or in combination, to genetic, autoimmune, and environmental factors (e.g., virus, obesity).
causes of diabetes
a disorder of glucose metabolism related to absent or insufficient insulin supply and/or poor use of the available insulin.
diabetes is primarily
2 most common are type 1 and type 2
-2 other classes are gestational diabetes and other specific types of diabetes with various causes.
American Diabetes Association (ADA) recognizes 4 different classes of diabetes.
is a hormone made by the β cells in the islets of Langerhans of the pancreas.
-continuously released into the bloodstream in small amounts, with increased release when food is ingested
Insulin
a stable, normal glucose range of about 74 to 106 mg/dL (4.1 to 5.9 mmol/L). The amount of insulin secreted daily by an adult is about 40 to 50 U, or 0.6 U/kg of body weight.
Insulin lowers blood glucose and facilitates
excess glucose as glycogen.
Liver and muscle cells store
gluconeogenesis, enhances fat deposition of adipose tissue, and increases protein synthesis. For this reason, insulin is an anabolic, or storage, hormone.
rise in plasma insulin after a meal inhibits
the release of stored glucose from the liver, protein from muscle, and fat from adipose tissue.
fall in insulin level during normal overnight fasting promotes
specific receptors for insulin and are considered insulin-dependent tissues.
-Insulin is required to “unlock” these receptor sites, allowing the transport of glucose into the cells to be used for energy
Skeletal muscle and adipose tissue have
require an adequate glucose supply for normal function. Although liver cells are not considered insulin-dependent tissue, insulin receptor sites on the liver facilitate uptake of glucose and its conversion to glycogen.
Other tissues (e.g., brain, liver, blood cells) do not directly depend on insulin for glucose transport but
Other hormones (glucagon, epinephrine, growth hormone [GH], cortisol) work against the effects of insulin. They are
counterregulatory hormones (work against insulin)
(1) stimulating glucose production and release by the liver and (2) decreasing the movement of glucose into the cells. The counterregulatory hormones and insulin work together to maintain blood glucose levels within the normal range by regulating the release of glucose for energy during food intake and periods of fasting.
hormones increase blood glucose levels by (counterregulatory hormones)
Ifrom its precursor, proinsulin.
insulin is synthesized
insulin and C-peptide, and the 2 substances are released in equal amounts. Therefore measuring C-peptide in serum and urine is a useful clinical indicator of pancreatic β-cell function and insulin levels.
Enzymes split proinsulin to form
juvenile-onset diabetes or insulin-dependent diabetes mellitus (IDDM), accounts for about 5% to 10% of all people with diabetes.
-affects people under 40 years of age, although it can occur at any age.
Type 1 diabetes, formerly known as
the body develops antibodies against insulin and/or the pancreatic β cells that make insulin. This eventually results in not enough insulin for a person to survive
Type 1 diabetes is an autoimmune disorder in which
genetic predisposition and exposure to a virus are factors that may contribute to the development of immune-related type 1 diabetes.
cause Type 1 diabetes
to human leukocyte antigens (HLAs)
-HLA types is exposed to a viral infection, the β cells of the pancreas are destroyed, either directly or through an autoimmune process.
Predisposition to type 1 diabetes is related
HLA-DR3 and HLA-DR4.
risk for type 1 diabetes include
type 1 diabetes that is strongly inherited and not related to autoimmunity.
Idiopathic diabetes is a form of
a slowly progressing autoimmune form of type 1 diabetes. It occurs in adults and is often mistaken for type 2 diabetes.
Latent autoimmune diabetes in adults (LADA),
the person’s pancreas can no longer make enough insulin to maintain normal glucose. Once this occurs, the onset of symptoms is usually rapid. Patients often are initially seen with impending or actual ketoacidosis. The patient usually has a history of recent and sudden weight loss and the classic symptoms of polydipsia (excessive thirst), polyuria (frequent urination), and polyphagia (excessive hunger).
Manifestations develop when (type 1)
person with type 1 diabetes requires insulin from an outside source (exogenous insulin) to sustain life. Without insulin, the patient will develop diabetes-related ketoacidosis (DKA), a life-threatening condition resulting in metabolic acidosis. Newly diagnosed patients may have a remission, or “honeymoon period,” for 3 to 12 months after starting treatment. During this time, the patient needs little injected insulin because β-cell insulin production is still sufficient for healthy blood glucose levels. Eventually, as more β cells are destroyed and blood glucose levels increase, the honeymoon period ends and the patient will require insulin on a permanent basis.
Type 1 DM and severity of no insulin
, accounts for about 90% to 95% of people with diabetes.
Type 2 diabetes, formerly known as adult-onset diabetes or non–insulin-dependent diabetes mellitus (NIDDM)
overweight or obese, being older, and having a family history of type 2 diabetes
risk factors of type 2
a combination of inadequate insulin secretion and insulin resistance.
Type 2 diabetes is characterized by
pancreas usually makes some endogenous (self-made) insulin. However, the body either does not make enough insulin or does not use it effectively, or both.
Type 2 diabetes insulin issue
a condition in which body tissues do not respond to the action of insulin because insulin receptors are unresponsive, are insufficient in number, or both.
first factor is insulin resistance,
on skeletal muscle, fat, and liver cells.
Most insulin receptors are located
a marked decrease in the ability of the pancreas to make insulin, as the β cells become fatigued from the compensatory overproduction of insulin or when β-cell mass is lost
- α cells of the pancreas increase production of glucagon.
second factor in the development of type 2 diabetes is
which is inappropriate glucose production by the liver. Instead of properly regulating the release of glucose in response to blood levels, the liver does so in a haphazard way that does not correspond to the body’s needs at the time.
This leads to a third factor, type 2 DM
s altered production of hormones and cytokines by adipose tissue (adipokines). Adipokines secreted by adipose tissue appear to play a role in glucose and fat metabolism and are likely to contribute to the development of type 2 diabetes
fourth factor for type 2 DM
cause chronic inflammation, a factor involved in insulin resistance, type 2 diabetes, and cardiovascular disease (CVD)
adipokines (in adipose tissue)
adiponectin and leptin.
2 main adipokines thought to affect insulin sensitivity are
type 2 diabetes
brain, kidneys, and gut have roles in the development of
increased glucose levels, abdominal obesity, high BP, high levels of triglycerides, and decreased levels of high-density lipoproteins (HDLs)
-person with 3 of the 5 components is considered to have metabolic syndrome
Metabolic syndrome has 5 components: (develop type 2 DM)
50% to 80% of β cells are no longer secreting insulin
-average person has had type 2 diabetes for 6½ years.
signs and symptoms of hyperglycemia develop when about
impaired glucose tolerance (IGT), impaired fasting glucose (IFG), or both.
Prediabetes is defined as
the 2-hour oral glucose tolerance test (OGTT) values are 140 to 199 mg/dL (7.8 to 11.0 mmol/L).
diagnosis of IGT is made if
fasting blood glucose levels are 100 to 125 mg/dL (5.56 to 6.9 mmol/L).
IFG is diagnosed when
such as fatigue, frequent infections, or slow-healing wounds.
symptoms of diabetes
pregnancy and occurs in about 2% to 10% of pregnancies in the United States
Gestational diabetes develops during
cesarean delivery, and their babies have increased risk for perinatal death, birth injury, and neonatal complications.
Women with gestational diabetes have a higher risk for
at 24 to 28 weeks of gestation
Women with an average risk for gestational diabetes are screened using an OGTT
6 weeks postpartum.
Most women with gestational diabetes have normal glucose levels within
of developing type 2 diabetes within 16 years.
Women with a history of gestational diabetes have up to a 63% chance
Cushing syndrome, hyperthyroidism, recurrent pancreatitis, cystic fibrosis, hemochromatosis, and parenteral nutrition.
-Common drugs that can induce diabetes include corticosteroids (prednisone), thiazides, phenytoin (Dilantin), and atypical antipsychotics (e.g., clozapine [Clozaril]).
other medical issues cause DM (causes abnormal blood glucose)
are polyuria, polydipsia, and polyphagia
classic symptoms of type 1 DM
is a result of cellular malnourishment when insulin deficiency prevents cells from using glucose for energy.
Polyphagia (TYPE 1 DM)
the body cannot get glucose and instead breaks down fat and protein to try to make energy.
Weight loss may occur because (TYPE 1 DM)
more common manifestations associated with type 2 diabetes are fatigue, recurrent infections, recurrent vaginal yeast or candida infections, prolonged wound healing, and vision problems.
-polyuria, polydipsia, and polyphagia
common symp type 2 DM
. A1C of 6.5% or higher
2. Fasting plasma glucose (FPG) level of 126 mg/dL (7.0 mmol/L) or greater. Fasting is defined as no caloric intake for at least 8 hours
3. A 2-hour plasma glucose level of 200 mg/dL (11.1 mmol/L) or greater during an OGTT, using a glucose load of 75 g
4. In a patient with classic symptoms of hyperglycemia (polyuria, polydipsia, unexplained weight loss) or hyperglycemic crisis, a random plasma glucose level of 200 mg/dL (11.1 mmol/L) or greater
diagnosis of diabetes is made using 1 of the following 4 methods:
recent severe restrictions of dietary carbohydrate, acute illness, drugs (e.g., contraceptives, corticosteroids), and restricted activity, such as bed rest. A patient with impaired gastrointestinal (GI) absorption or who has recently taken acetaminophen may have false-negative results.
factors that can falsely elevate values include
glycosylated hemoglobin (Hgb) as a percentage of total Hgb.
-glucose stays attached to the red blood cell (RBC) for the life of the cell (about 120 days).
A1C measures the amount of
a measurement of blood glucose levels over the previous 2 to 3 months, with increases in the Hb A1C reflecting elevated blood glucose levels.
A1C provides
greater convenience, since fasting is not needed. Diseases affecting RBCs (e.g., iron deficiency anemia, sickle cell anemia) can influence the A1C and should be considered when interpreting results.
A1C has several advantages over the FPG, including
The eAG = 28.7 × A1C − 46.7. For example, an A1C of 8.0% is equivalent to a glucose level of 183 mg/dL.
estimated average glucose (eAG) can be determined from the A1C.
It is formed by a chemical reaction of glucose with plasma protein. It reflects glycemia in the previous 1 to 3 weeks. Fructosamine levels may show a change in blood glucose levels before A1C does. It is used for people with hemoglobinopathies, or for short-term measurement of glucose levels, for instance, after a change in medication or during pregnancy.
Fructosamine is another way to assess glucose levels.
primarily done to help distinguish between autoimmune type 1 diabetes and diabetes from other causes. Autoantibodies can develop to 1 or several autoantigens, including GAD65, IA-2, or insulin.
Islet cell autoantibody testing is
insulin, oral agents (OAs), and noninsulin injectable agents.
3 major types of glucose-lowering agents (GLAs) used in the treatment of diabetes are
n to survive. They often use multiple daily injections of insulin (often 4 or more) or continuous insulin infusion via an insulin pump to adequately manage blood glucose levels.
type 1 diabetes require exogenous insuli
common bacteria (e.g., Escherichia coli) or yeast cells using recombinant deoxyribonucleic acid (DNA) technology
- insulin was extracted from beef and pork pancreases.
insulin is derived from
their onset, peak action, and duration
Insulins differ by
as rapid-acting, short-acting, intermediate-acting, and long-acting insulin
insulin is categorized
insulin approach that most closely mimics endogenous insulin production is the
basal-bolus plan (often called intensive or physiologic insulin therapy).
consists of multiple daily insulin injections (or an insulin pump) together with frequent self-monitoring of blood glucose (or a continuous glucose monitoring system).
-Injections include rapid- or short-acting (bolus) insulin before meals and intermediate- or long-acting (basal) background insulin once or twice a day.
basal-bolus plan (often called intensive or physiologic insulin therapy).
achieve a glucose level as close to normal as possible, as much of the time as possible. This is referred to as “.”
time in range
aspart (NovoLog), glulisine (Apidra), and lispro (Humalog), have an onset of action of about 15 minutes.
-should be injected within 15 minutes of mealtime.
-most closely mimic natural insulin secretion in response to a meal.
Rapid-acting synthetic insulin analogs, which include
has an onset of action of 30 to 60 minutes. It is injected 30 to 45 minutes before a meal to ensure that the insulin is working at the same time as meal absorption.
-more likely to cause hypoglycemia because of a longer duration of action.
Short-acting regular insulin
a long- or intermediate-acting basal (background) insulin to maintain blood glucose levels in between meals and overnight.
-Without 24-hour background insulin, people with type 1 diabetes are more prone to developing DKA
mealtime insulin, people with type 1 diabetes use
adequately manage blood glucose levels.
people with type 2 diabetes who use OAs will need basal insulin to
degludec (Tresiba), detemir (Levemir), and glargine (Lantus, Toujeo, Basaglar).
-type of insulin is released steadily and continuously.
-does not have a peak of action bc they lack peak action time, the risk for hypoglycemia from this type of insulin is greatly reduced.
long-acting insulins include
often given twice daily
detemir is (long-acting insulins )
diluted or mixed with any other insulin or solution in the same syringe.
Glargine and detemir must not be
basal insulin. It has a duration of 12 to 18 hours.
Intermediate-acting insulin (NPH) can be used as a
it has a peak ranging from 4 to 12 hours, which can result in hypoglycemia. NPH can be mixed with short- and rapid-acting insulins. It should never be given IV.
The disadvantage of NPH is that
NPH, lispro protamine, and aspart protamine.
-They are cloudy because they contain a protein called protamine, which makes them work longer.
All insulins are clear solutions except
with intermediate-acting insulin in the same syringe. This allows the patient to have both mealtime and basal coverage without having to give 2 separate injections.
For those who want to use only 1 or 2 injections per day, a short- or rapid-acting insulin is mixed
convenience to patients, who do not have to draw up and mix insulin from 2 different vials. This is especially helpful to those who lack the visual, manual, or cognitive skills to mix insulin themselves.
Premixed formulas offer
and can make it less effective. Insulin vials and pens in use may be left at room temperature for up to 4 weeks unless the room temperature is higher than 86° F (30° C) or below freezing (less than 32° F [0° C]).
-Store unopened insulin vials and pens in the refrigerator.
Extreme temperatures alter the insulin molecule
stable for up to 1 week when stored in the refrigerator.
Prefilled syringes with 2 different insulins are
stable up to30 days.
-store syringes in a vertical position with the needle pointed up to avoid clumping of suspended insulin in the needle.
Syringes with only 1 type of insulin are
Before injection, gently roll prefilled syringes between the palms 10 to 20 times to warm the insulin and resuspend the particles.
-Some insulin combinations cannot be prefilled and stored because the mixture can alter the onset, action, and/or peak times of either insulin.
Rules for insulin
- given subcutaneous injection
-given IV when immediate onset of action is desired
-Insulin is not taken orally because it is inactivated by gastric fluids. - avoid injecting insulin IM because rapid and unpredictable absorption could result in hypoglycemia.
-Caution the patient about injecting into a site that is to be exercised=This could increase the rate of insulin absorption and speed the onset of action, resulting in hypoglycemia.
-patients to rotate the injection within and between sites.= better absorption - Injections are rotated systematically across the board, with each injection site at least ½ to 1 inch away from the previous injection site. It can be helpful to inject fast-acting insulin into faster-absorbing sites and slow-acting insulin into slower absorbing sites.
Administration of insulin
the abdomen, followed by the arm, thigh, and buttock.
fastest subcutaneous absorption is from
U100. This means that 1 mL contains 100 U of insulin. U100 insulin must be used with a U100-marked syringe.
Most commercial insulin is available as
1.0, 0.5, and 0.3 mL.
Disposable plastic insulin syringes are available in a variety of sizes, including
doses of 50 U or less.
0.5-mL size may be used for
30 U or less
-0.5- and 0.3-mL syringes are in 1-unit increments. This provides more accurate delivery when the dose is an odd number.
0.3-mL syringe can be used for doses of
50 U of insulin. The 1.0-mL syringe is in 2-unit increments
1.0-mL syringe is necessary for patients who inject more than
6 mm (¼ in), 8 mm (5⁄16 in), and 12.7 mm (½ in).
Insulin syringe needles come in 3 lengths:
28, 29, 30, and 31.
-higher the gauge number, the smaller the diameter, thus resulting in a more comfortable injection
needle gauges available are
a 90-degree angle. For extremely thin or muscular patients in the hospital, perform injections at a 45-degree angle. At home, patients inject at a 90-degree angle using the shortest needle desired.
-Pinching up of the skin to avoid IM injection is no longer done because of the use of short needles.
Insulin injections are typically given at
4 mm (5⁄32 in), 5 mm (3⁄16 in), 8 mm (5⁄16 in), and 12.7 mm (½ in) and in 3 gauges: 29, 31, and 32.
Pen needles are available in lengths of
delivers a continuous subcutaneous insulin infusion through a small device worn on the belt, in a pocket, or under clothing.
-rapid-acting insulin
insulin pump
an insulin pump that is a tubing-free system
Insulet Corporation has
All insulin pumps are programmed to deliver a continuous infusion of rapid-acting insulin 24 hours a day, known as thebasal rate
basal rate
increased or decreased based on carbohydrate intake, activity changes, or illness. Pump users need different basal rates at different times of the day.
Basal insulin can be temporarily
is the potential for keeping blood glucose levels in a tighter range with a goal of eliminating both high and low glucose.
major advantage of the insulin pump
infection at the insertion site, an increased risk for DKA if the insulin infusion is disrupted, the cost of the pump and supplies, and being attached to a device.11
Potential challenges of insulin pump therapy include
hypoglycemia, allergic reactions, lipodystrophy, hypertrophy, and the Somogyi effect.
Problems associated with insulin therapy include
the same injection sites are used frequently. The use of human insulin has significantly reduced the risk for lipodystrophy.
Lipodystrophy (loss of subcutaneous fatty tissue) may occur if (infusion pump issue)
which is uncommon, is the wasting of subcutaneous tissue and presents as indentations in injection sites
Atrophy,
happens more often and is a thickening of the subcutaneous tissue. It eventually regresses if the patient does not use the site for at least 6 months. Injecting into a hypertrophied site may result in erratic insulin absorption.
Hypertrophy (infusion pump issue)
Hyperglycemia in the morning may be due to the
Somogyi effect
high dose of insulin causes a decline in blood glucose levels during the night. As a result, counterregulatory hormones (e.g., glucagon, epinephrine, GH, cortisol) are released. They stimulate lipolysis, gluconeogenesis, and glycogenolysis, which in turn cause rebound hyperglycemia.
Somogyi effect
= is also characterized by hyperglycemia that is present on awakening.
-Two counterregulatory hormones (GH and cortisol), which are excreted in increased amounts in the early morning hours, may be the cause of this phenomenon.
- most severe when GH is at its peak in adolescence and young adulthood.
dawn phenomenon
a bedtime snack, reducing the dose of insulin, or both
treatment for Somogyi effect is
is an increase in insulin or an adjustment in administration time.
treatment for dawn phenomenon
is a rapid-acting inhaled insulin
- given at the beginning of each meal or within 20 minutes after starting a meal
-must be used in combination with long-acting insulin in patients with type 1 diabetes. It should not be used to treat diabetic ketoacidosis.
Afrezza
must be used in combination with long-acting insulin in patients with type 1 diabetes. It should not be used to treat diabetic ketoacidosis. Patients with chronic lung disease, such as asthma or COPD, or who smoke, should not use Afrezza because bronchospasm can occur. Other common adverse reactions are hypoglycemia, cough, and throat pain or irritation.
Afrezza (inhaled insulin)
improve the mechanisms by which the body makes and uses insulin and glucose.
OAs and noninsulin injectable agents work to
primarily work on 3 defects of type 2 diabetes: (1) insulin resistance, (2) decreased insulin production, and (3) increased hepatic glucose production
OAs and noninsulin injectable agents primarily work on 3 defects of type 2 diabetes:
metformin. It is the only drug in the biguanide class
most widely used OA is
is the most effective first-line treatment for type 2 diabetes
Metformin
Glucophage (immediate release), Glucophage XR (extended release), Fortamet (extended release), and Riomet (liquid).
Forms of metformin include
to reduce glucose production by the liver. It enhances insulin sensitivity at the tissue level and improves glucose transport into the cells. It also has beneficial effects on plasma lipids.
primary action of metformin is
prevent type 2 diabetes in those with prediabetes who are younger than age 60 and have risk factors, such as hypertension or a history of gestational diabetes.
Metformin also ised
Patients who are undergoing surgery or radiologic procedures that involve the use of a contrast medium need to temporarily discontinue metformin before surgery or the procedure.
-should not resume the metformin until 48 hours afterward, once their serum creatinine has been checked and is normal.
Metformin ALERT
the dose before each meal based on the current blood glucose level and the carbohydrate content of the meal.
Patients using rapid-acting insulin can adjust
, such as multiple daily injections or the use of an insulin pump, allows considerable flexibility in food selection and can be adjusted for changes from usual eating and exercise habits.
Intensified insulin therapy