Endocrine system

Endocrine System

• a network of glands that produce and secrete hormones

• hormones act as chemical messengers in the body

Functions of endocrine system

• regulate growth & dev

• controls metabolism

• influences sexual reproduction & function

• maintains mood stability

A client has elevated blood glucose levels. Which hormone response demonstrates a negative feedback mechanism?

Release of insulin

The nurse is reviewing lab results for a client with a thyroid disorder. Which finding reflects negative feedback regulation?

High thyroid hormone levels causing decreased TSH secretion

Which situation is an example of a positive feedback mechanism?

Release of oxytocin during labor contractions

A nurse is caring for a client in labor. Which finding demonstrates a positive feedback loop?

Contractions increase as more oxytocin is released

tropic hormones

regulate other endocrine glands (TSH)

nontropic hormones

directly stimulate cellular metabolism and other activities (i.e: growth hormone)

Pituitary gland

“master gland” controls many body functions through hormones

when is glucagon released?

when serum glucose levels fall, insulin declines, or glucose needs increase

what does glucagon do?

increase serum glucose

when is insulin released?

when serum glucose levels increases

amylin

• released from beta cells

  • work synergistically w/ insulin to control glucose by suppressing glucagon, slowing gastric emptying

what hormones do the thyroid produce?

• thyroxine(T4)

• Triiodothyronine(T3)

• calcitonin

how does PTH increases serum calcium?

• increasing osteoblast activity

• increasing calcium absorption in GI tract

• increasing calcium reabsorption in kidneys

what does ACTH do?

stimulates adrenal cortex to produce corticosteroid hormones

What is Diabetes Mellitus (DM)?

 A group of metabolic disorders characterized by hyperglycemia due to defects in insulin production, insulin action, or both.

 What happens with amylin deficiency in DM?

 Increased glucagon, faster gastric emptying, decreased satiety.

 What metabolic processes are disrupted in DM?

Carbohydrate, protein, and fat metabolism.

Which tissue can use glucose without insulin?

the brain

 Normal fasting blood glucose?

70–99 mg/dL

Normal 2-hour postprandial glucose?

<140 mg/dL

Prediabetes fasting glucose?

100–125 mg/dL

 Diabetes fasting glucose?

 ≥126 mg/dL (on repeat testing)

What level defines hypoglycemia?

 <70 mg/dL

 Severe hypoglycemia level?

<54 mg/dL

High-risk populations for DM?

African Americans, Hispanics, Native Americans, some Asians/Pacific Islanders

What causes hyperglycemia?

Excess carbs, insufficient medication

What is Diabetic Ketoacidosis (DKA)?

Life-threatening condition from insulin deficiency causing ketone buildup

 Causes of hypoglycemia?

Too little food, too much insulin, increased activity

What causes chronic complications in DM?

 Long-term hyperglycemia

 Major macrovascular complications? (DM)

Heart disease, stroke, hypertension

Microvascular complications?(DM)

Retinopathy, nephropathy, neuropathy

Other complications of DM?

Amputations, infections, poor wound healing

Classic signs of hyperglycemia?

Polyuria, polydipsia, polyphagia

Other symptoms of DM?

Weight loss, blurred vision, fatigue

pathophysiology of T1DM?

Autoimmune destruction of pancreatic beta cells→Absolute insulin deficiency

etiology?

• exact cause is unknown

• viral infection

• environmental factors

• genetically susceptible individuals

cant be prevented

treatment for T1DM?

Lifelong insulin therapy(injection or pump)

What is pramlintide (Symlin)?

Synthetic amylin that slows gastric emptying and reduces glucagon secretion

decreases appetite

must be used with insulin

Primary problem in early T2DM?

Insulin resistance

liver cannot suppress glucose production → hyperglycemia

high insulin levels (hyperinsulinemia)

What happens later in T2DM?

Decreased insulin production = pancreatic beta cell function decreases

Major risk factors for T2DM?

Obesity, aging, family history, inactivity, impaired glucose metabolism

Initial treatment for T2DM?

Oral antidiabetic medications

insulin is needed as disease progresses

A patient with DM presents with fruity breath and Kussmaul respirations. What condition is suspected?

Diabetic ketoacidosis (DKA)

 A patient is shaky, sweaty, and confused. What should the nurse suspect?

Hypoglycemia

A nurse is teaching a client about the role of insulin. Which statement by the client indicates correct understanding?

“Insulin acts like a key to allow glucose into cells.”

A client has a fasting blood glucose of 130 mg/dL on two separate tests. How should the nurse interpret this?

Diabetes Mellitis

A nurse is caring for a client with diabetic ketoacidosis (DKA). What is the underlying cause?

lac of insulin leading to fat breakdown

Which client is at highest risk for developing Type 2 diabetes?

 A 55-year-old with obesity and sedentary lifestyle

Which complications are considered microvascular complications of diabetes?

Retinopathy, Nephropathy, Neuropathy

A client with long-term uncontrolled diabetes is at risk for which condition?

Thickened blood vessels

Which finding is most concerning in a client with diabetes?

Blood glucose of 50 mg/dL with confusion

A nurse is caring for four clients. Which client should the nurse assess first?

 B. Client with blood glucose 60 mg/dL who is diaphoretic and confused

a client reports excessive urination and thirst. What mechanism explains this

glucose pulling water into urine