Homeostasis: Glucose Regulation

The ultimate end result of glucose metabolism

cellular use of glucose for energy synthesis

Pancreas Endocrine Function

secretes insulin and glucagon to regulate blood
glucose levels

Pancreas Exocrine Function

secretes enzymes for digestion such as amylase and lipase

Glucagon

released in response to blood glucose levels to
prevent hypoglycemia

Insulin

key hormone that unlocks the cell to allow
absorption of glucose

Digestive System Process in Hyperglycemia

breaks down carbohydrates to simple sugars called glucose

Circulatory System in Hyperglycemia

carries the glucose to the brain and muscles for fuel

Insulin Pathophysiology

• produced in the pancreas by the islets of Langerhans in the beta cells

• regulates the concentration of circulating blood glucose by binding to receptors on liver, muscle and fat cells

As glucose binds to the cell receptors

glucose enters the cell and the concentration of circulating glucose decreases

lack of insulin

cells are not able to uptake the glucose that is needed for energy

Liver

elease glucagon stores and stimulate glucose
production through gluconeogenesis and glycogenolysis

Gluconeogenesis

generates glucose from non-carbohydrate
sources, such as proteins, lipids, pyruvate, or lactate

Glycogenolysis

mainly occurs in the hepatocytes of the liver
and myocytes of the muscles. Breaking down of stored glycogen

risk factors for prediabetes and diabetes

Being overweight, age over 45, physically active less than 3x’s per week

Type I Diabetes

• An autoimmune dysfunction involving the destruction of beta cells, which produce insulin in the islets of Langerhans of the pancreas.

• Leading to absolute insulin deficiency

Type 2 Diabetes

• A progressive condition due to:
  • insulin resistance
  • impaired insulin secretion

• Leading to relative insulin deficiency

Prediabetes

• increased hemoglobin A1C 5.7–6.4%

• increases risk for diabetes and cardiovascular disease (CVD)

• associated with obesity, dyslipidemia with high triglycerides and/or low HDL cholesterol, and hypertension

Lifestyle Modifications for Type 2 Diabetes

• Nutrition

• Physical activity

• Tobacco use

• Monitor for Infection

Diabetes self-management education and support programs

• Provide education and support

• To develop and maintain healthy behaviors

• Close Glucose Monitoring and adjustment during periods of illness and surgery

Gestational Diabetes

glucose intolerance when pregnant due to secretion of placental hormones

Primary Risk Factors for Diabetes

• Age

• BMI

• Medications

Age Risk Factor for Diabetes

• Testing should begin at
  no later than age 45 years for all patients

• Screening should be considered in adults of any age with overweight or obesity and one or more risk factors 

BMI Risk Factor for Diabetes

≥25 kg/m2

Medications Risk Factors for Diabetes

glucocorticoids, thiazide diuretics, some HIV medications, and atypical antipsychotics

Hyperglycemia Early Clinical Manifestions

• Polyuria

• Polyphagia

• Polydipsia

Signs of hyperglycemia

Recurrent infections, fatigue, weakness,
vision changes, tingling or numbness in hands or feet, dry skin, skin lesions or wounds that are slow to heal

Patient History for Diabetes

• Current medications

• Personal or family medical history markers
  • Central obesity
  • Diabetes
  • Hypertension
  • Cardiovascular disease
  • Cancer

• Review of symptoms

Physical Exam for Diabetes

• Blood pressure

• Height, weight, BMI

• Focus on:
  • Skin
  • Neurologic exam
  • Dental Exam
  • Foot Exam

Diagnostic Studies for Diabetes

• Hemoglobin A1C Test

• Fasting blood glucose

• Lipid panel

• BUN and creatinine (on a basic
  metabolic panel)

• Urinalysis microalbuminuria,
  glucose, ketones

Glycated Hemoglobin (A1C) Test

• Shows amount of glucose attached to hemoglobin molecules over RBC life span (90-120 days)

• Determines glycemic level over time- monitors treatment

• Measurement of glycemic control over the previous 2 to 3 months

A1C Goal in Diabetes

Less than 7.0%

Normal A1C (4%-5.7%)

reduces risk of retinopathy, nephropathy, and neuropathy

Casual Blood Glucose Concentration Criteria for Diabetes

greater than 200 mg/dL (without regard to time
since last meal)

Fasting Blood Glucose Criteria for Diabetes

greater than 126 mg/dL (no caloric intake within 8 hr of testing)

Oral Glucose Tolerance Test Criteria for Diabetes

2-hr glucose greater than 200 mg/dL

Glycosylated hemoglobin (A1C) Criteria for Diabetes

greater than 6.5%

Diabetes Management Goal

• normalize insulin activity and blood glucose levels

• ADA now recommends HgbA1c less than 7%

Diabetes Management

• Nutritional therapy

• Exercise

• Monitoring

• Pharmacologic therapy

• Education

Diabetic Nutritional Therapy

• Carbohydrates: 45% total daily intake

• Protein: 15% to 20% of total daily intake, depending on kidney function

• Unsaturated and polyunsaturated fats: 20% to 35% of total daily intake

• Low saturated fats

• Include omega-3’s and fiber

Importance of low saturated fats for Diabetics

to decrease LDL, assist with weight loss for
prevention of secondary diabetes, and reduce risk of heart disease

Importance of omega-3’s and fiber for Diabetics

to lower cholesterol, improve blood glucose, prevention of secondary diabetes, and reduce risk of heart disease

Carb counting

• Specialized for individuals

• Counting the number of grams of carbohydrates in a meal and
  matching that to your insulin dose

• 1 serving size is 15 grams

• Most adults eat 45-60 grams of carbohydrates per meal

• Include fruits, vegetables, whole grains, legumes, low-fat milk

Calorie Intake

• 50%-60% from carbohydrates

• 20%-30% from fat

• Remaining 10%-20% from protein

Glycemic Index

used to describe rise in blood glucose levels after carbohydrate-containing food is consumed

High Glycemic Foods

Increase blood sugar faster

• Juices

• Hard candies

• Sugar packets

• White bread

• Dried fruit

Complex Carbohydrates

Take longer to convert to glucose

• Whole grain bread

• Beans

• Nuts

• Oatmeal

• Greek yogurt

Exercise for Diabetes

• Perform physical activity at least 3 times per week, no more
  than 2 consecutive days without

• Perform resistance training twice a week if type 2

• Exercise at the same time of day for the same duration

• Use proper footwear

• Avoid trauma to lower extremities

• Inspect feet

• Stretch for 10 to 15 minutes before exercising

Exercise DO NOTS for Diabetes

• Avoid exercise in extreme heat or cold

• Avoid exercise during periods of poor metabolic control

Self-monitoring of blood glucose (SMBG)

• Enables patients to self manage

• Detects hyperglycemia, hypoglycemia

• Patient training important

• Immediate information about glucose levels

Continuous Glucose Monitoring Systems

• sensor under the skin checks glucose

• A transmitter sends data to a receiver and it may be part of an insulin pump

Oral Antidiabetic Drugs

• Biguanides

• Sulfonylureas

• Meglitinides

• Alpha-glucosidase inhibitors

• Thiazolidinediones

• DPP-4 Inhibitors

• SGLT2 Inhibitor 

• Dopamine Receptor Agonists

Biguanides Metformin (Glucophage)

Drug of choice for initial therapy in most type 2 diabetics (also used in prediabetes) Lowers A1C 1-2%

• little risk of hypoglycemia

Biguanides Metformin (Glucophage) Mechanism of Action

lowers blood glucose and improves
glucose tolerance: inhibits glucose production of glucose by the liver; reduces glucose absorption in the gut; sensitizes insulin receptors in target tissues (fat and skeletal muscle) increasing glucose uptake in response to available insulin

Biguanides Metformin (Glucophage) Side Effects

decreased appetite, nausea, and diarrhea; decreases absorption of vitamin B12 and
folic acid; lactic acidosis; Must stop this medication 1 day prior to IV contrast and at least 48 hrs after

Biguanides Metformin (Glucophage) Nursing Considerations

Take with meals, check labs, caution with binge drinkers, and CHF on meds; watch creatinine levels

Insulin Mechanism of Action

Stimulates cellular transport of glucose

Insulin Adverse Effects/Interactions

• Hypoglycemia: watch for
  activation of SNS: tachycardia,
  palpitations, sweating, and
  nervousness and later headache,
  confusion, drowsiness, and fatigue
  (Treated with D50% or Glucagon if
  patient is unresponsive)

• SHOULD WEAR A MEDIC-ALERT
  BRACELET

• Beta adrenergic blockers: delay
  awareness of hypoglycemia, mask
  s/s associated with SNS stimuli

Hypoglycemia

Blood glucose < 70 mg/dl

• too much insulin or oral hypoglycemic agents

• too little food

• excessive physical activity

Hypoglycemia Nursing Considerations

• check the patient’s blood glucose level and correlate it with the patient’s symptoms

• If the patient’s blood glucose level is low, but they are not exhibiting any symptoms, the nurse should double-check the glucose level 

Hypoglycemia Early Clinical Manifestations

sweating, tremor, tachycardia, palpitation, nervousness, hunger

Hypoglycemia Later Clinical Manifestions

headache, lightheadedness, confusion, slurred speech, impaired coordination, emotional changes, irrational or combative behavior, double vision, drowsiness

Rapid Acting Insulin (lispro,aspart,glulisine)

mimics body secretion after meals; usually given 5-15 min before meals; 1 hr peak; 5 hr duration

Short Acting Insulin (regular)

given 30-60 mins before meals; 2-3 hr peak; 4-6 hr duration

Long-Acting Insulin (glargine detamir)

first thing in the morning or before bed; basal state; used to prevent nocturnal hyperglycemia; 3-6 hr onset and 24 hr duration

Hypoglycemia Severe Clinical Manifestations

disoriented behavior, seizures, loss of consciousness

Prevention: Hypoglycemia

• Consistent pattern of eating, administering insulin, and exercising.

• Routine blood glucose tests

• Identification bracelet

• Family/support education

• Carry simple sugar

• Avoid high-calorie, high-fat dessert foods

Autonomic neuropathy or beta-blockers to treat hypertension or cardiac dysrhythmias

may mask the typical symptoms of hypoglycemia

Management: Hypoglycemia

Implement rule of 15

• Consume 15 g of a simple carbohydrate

• Recheck glucose level in 15 minutes
  • Repeat above steps if still less than 70 gm/dL

• Avoid foods with fat

• Avoid overtreatment

• Give complex carbohydrate after recovery

simple carbohydrate examples

• ½ cup (4 oz) juice or regular soda

• Three glucose tablets (5 g each, read label)

• Hard candies, jelly beans, or gumdrops (read label for amount)

• 1 tbsp honey or 4 tsp sugar

Glucagon

• A hormone produced by the alpha
  cells of the pancreas that
  stimulates the liver to breakdown
  glycogen, the stored glucose.

• 1 mg IM, IV or SQ

• Onset is 8-10 minutes

Dextrose 50%

• 25 grams/50 ml

• Only used if patient is unresponsive or NPO

• Need IV access- preferred central
  line

• May raise blood glucose too high
  (may give ½ amp)

If the hyoglycemic patient is unconscious

place them in a lateral position to prevent aspiration and administer medication, and notify
the provider

Diabetic Ketoacidosis (DKA)

A metabolic derangement that results from a deficiency of insulin; highly acidic ketone bodies are formed, resulting in acidosis

Diabetic Ketoacidosis (DKA) Clinical Features

• Hyperglycemia

• Ketosis

• Acidosis

• Dehydration

Diabetic Ketoacidosis (DKA) Precipitating Factors

• Illness

• Infection

• Inadequate insulin

Severe Hyperglycemia Clinical Manifestions

• Polyuria, polydipsia, dehydration

• Fatigue

• Weakness

• Blurred vision

• Headache

• Orthostatic hypotension can occur

Ketoacidosis Clinical Manifestions

• Acetone breath

• Abdominal pain, nausea, vomiting
  (worsens fluid and electrolyte loss)

• Anorexia

• Kussmaul respirations 

• Mental status changes

Kussmaul respirations

deep hyperventilation; blowing off CO2

DKA Goals

• Improve circulatory volume and
  tissue perfusion (rehydration)

• Decrease blood glucose

• Correct acidosis (Acidosis – corrected
  gradually with insulin; administration of IV bicarbonate no longer routinely
  recommended)

• Correct electrolyte imbalances

DKA Assessment/monitoring

• Vital signs

• Frequent glucose checks

• Labs- complete metabolic panel

• Arterial blood gases

DKA Interventions

1. IV fluids

2. IV insulin

3. Monitor/replace electrolytes

Initial rehydration IV fluids

Bolus: 0.9 % sodium chloride(NS) 0.5 - 1 L/hr, for 2-3 hours

Rehydration after the first few hours

• NSS is the fluid of choice

• May need 200-500 mL/hr for several more hours

When blood glucose gets reaches 250-300 mg/dL we should prepare

To slow IV fluid rate and switch to a fluid with 5% dextrose

DKA & HHS- IV Insulin

• High alert medication (Dual sign off)

• Most common preparation is 1:1 concentration 1 unit of insulin per 1 mL NS

• Insulin is a slow, continuous infusion

• Check BG hourly, titrate per order/protocol

• Maintain IV insulin until SC insulin has been started (typically until bicarbonate levels are at least (15 to 18), and patient is able to eat) 

  
  

Hyperglycemic Hyperosmolar Syndrome (HHS)

• Metabolic disorder of type 2 diabetes resulting from a relative insulin deficiency initiated by an illness that raises the demand for insulin

• Life-threatening: high mortality rate

• Less common than DKA

• Often in older patients with no diabetes history or type 2 diabetes

• No ketoacidosis because patient has some circulating insulin

Often see history of: in HHS

• Inadequate fluid intake

• Infection or precipitation event

• Medications that exacerbate

• Polyuria

HHS Lab Values

• Glucose > 600 mg/dl

• Increased serum osmolality

• Absent/minimal ketone bodies

HHS – Clinical Manifestations

• Fewer signs and symptoms in early stages

• Profound dehydration, hypotension, tachycardia

• More varied neurological signs: hemiparesis, aphasia, Babinski reflex, nystagmus, hyperthermia, visual
  hallucinations, seizures, coma

End-stage neurological state for both HHS and DKA

coma

Nursing Management HHS

Administer

• IV fluids

• Insulin therapy

• Electrolytes

HHS Assessment

• Renal status

• Cardiopulmonary status- CARDIAC MONITOR

• Level of consciousness

Sick Day Management LABORATORY TESTS

• Test urine for ketones if blood glucose is above 240 mg/dL.

• Report the presence of moderate to large ketones, or ketonuria that lasts
  more than 24 hr.

Sick Day Management Education

• Monitor blood glucose every 2 to 4 hr.

• Continue to take insulin or OA as prescribed.

• Drink 8 to 12 oz (240 to 360 mL) of sugar-free decaffeinated liquid every hour.

• Use fluids containing sugar if blood glucose is below the provider’s parameters

Call the provider if (sick day management)

• unable to tolerate liquids.

• unable to eat soft foods, consume liquids equal to usual carbohydrate content.

• illness lasts longer than 2 days, if unable to take fluids, and the blood glucose remains 250 or greater

• fever is greater than 38.6° C (101.5° F) or increasing.