Endocrine System Flashcards
Exam 4 (Final)
The Endocrine system:
What does it do?
Secretes hormones
The Endocrine system:
What does it control? What does it take part in?
Controls metabolism,
transports substances across cell membrane,
fluid and electrolyte balance,
growth and development, adaptation,
and reproduction
The Endocrine system:
How is hormone production maintained? What does it involve?
Hormone production is maintained by a negative or positive feedback loop involving the hypothalamic–pituitary axis.
Endocrine Dysfunction:
What occurs?
Subnormal hormone production as a result of gland destruction or malformation
Endocrine Dysfunction:
What else can occur?
Hormone excess
Endocrine Dysfunction:
How does production of abnormal hormone occur?
Production of abnormal hormone resulting from gene mutation
Endocrine Dysfunction:
How do hormone receptor disorders result?
Hormone receptor disorders resulting from autoimmune processes
Endocrine Dysfunction:
Disorders of hormone transport or metabolism result in what?
Disorders of hormone transport or metabolism, resulting in increased levels of “free” hormones in the blood
The Hypothalamus and Pituitary Gland
What do they share?
They share two connecting pathways:
The Hypothalamus and Pituitary Gland
They share two connecting pathways: what are they?
- a rich vascular network that connects hypothalamus to anterior pituitary,
- and nerve fibers that link the hypothalamus with the posterior pituitary.
The Hypothalamus and Pituitary Gland:
What do they control?
They control the
thyroid gland,
adrenal glands,
gonads, and
exert control over growth and metabolism.
The Hypothalamus and Pituitary Gland:
What is referred to as the master gland?
Pituitary is referred to as the master gland.
The Hypothalamus and Pituitary Gland:
What is hypothalamus?
Hypothalamus is the coordinating center of the brain.
The Thyroid and Parathyroid Glands
What does the thyroid gland do?
Thyroid gland- Produces, stores, and secretes thyroid hormones T3 and T4
The Thyroid and Parathyroid Glands
Each lobe of the thyroid contains what?
Each lobe of the thyroid gland contains two parathyroid glands.
The Thyroid and Parathyroid Glands
What synthesizes T3 and T4?
Tyrosine (amino acid) and iodide synthesize T3 and T4, stored in the colloid of the follicular cell until needed.
The Thyroid and Parathyroid Glands
What helps transport T3 and T4? Where are they manufactured?
Plasma proteins help to transport T3 and T4 , and are manufactured in the liver.
The Thyroid and Parathyroid Glands
What kind of condition can damage to liver produce?
Damage to liver can produce a condition that resembles hyperthyroidism.
Thyroid and Parathyroid hormones
Thyroid hormones: What are they and what produces them?
The follicular cells of the thyroid glands produce thyroid hormones thyroxine (T4) and triiodothryronine (T3).
Thyroid and Parathyroid hormones
Thyroid hormones: What do T3 and T4 do? What does this lead to?
Both T3 and T4 increase metabolism, which causes an increase in oxygen use and heat production in all tissues.
Thyroid and Parathyroid hormones
Thyroid hormones: What produces calcitonin?
The parafollicular cells produce Calcitonin
Thyroid and Parathyroid hormones
The parafollicular cells produce Calcitonin:
What does calcitonin inhibit?
Inhibits calcium reabsorption in the GI tract
Thyroid and Parathyroid hormones
The parafollicular cells produce Calcitonin:
What does calcitonin increase?
Increases calcium excretion from kidney
Thyroid and Parathyroid hormones
Parathyroid hormone: What is produced by?
Produced by the parathyroid glands
Thyroid and Parathyroid hormones
Parathyroid hormone: What does it promote?
Promotes bone resorption
Thyroid and Parathyroid hormones
Parathyroid hormone: What does it increase?
Increases calcium reabsorption
Increases calcium blood levels
Thyroid and Parathyroid hormones
What does vitamin D do?
Vitamin D acts on intracellular enzymes in intestinal mucosa to increase calcium absorption.
The Pancreas:
Has what kind of functions?
Endocrine functions
Exocrine functions
The Pancreas:
Endocrine functions: What occurs?
The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types: What are they?
Alpha cells
Beta cells
Delta cells
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
Alpha cells?
Alpha cells which secrete glucagon
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
Beta cells?
Beta cells which secrete insulin.
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
Delta cells?
Delta cells which secrete somatostatin
The Pancreas:
Exocrine functions: What does it involve?
Involves the secretion of digestive enzymes into the duodenum.
The Pancreas:
What do C-peptide levels measure?
C-peptide levels measure the degree of beta-cell activity and can assist in dx of types 1 and 2 diabetes.
The Pancreas:
What do low C-peptide levels indicate? What does this lead to?
Low C-peptide = autodestruction of beta cells; no insulin production = type 1 diabetes
Insulin:
What is it?
Insulin is an anabolic hormone
Insulin:
What is it responsible for?
responsible for blood glucose concentrations and storage of carbohydrates, proteins, and fat
Insulin:
What does it facilitate:
Facilitates use of glucose for energy
Facilitates cellular transport of glucose, amino acids, and fatty acids across cell membranes
Insulin:
What increases the production of insulin?
Elevated plasma levels of glucose increase the secretion of insulin.
Insulin:
What decreases the production of insulin?
Lower levels of glucose decrease insulin output.
Insulin:
Insulin resistance: What is it a characteristic of?
It is a characteristic of type 2 diabetes mellitus.
Insulin:
Insulin resistance: What is it?
It is a physiologic condition in which a person needs more insulin to lower serum glucose effectively than would normally be required.
Insulin:
Insulin resistance: What does this eventually lead to?
Beta cell exhaustion results when the pancreas must keep up with the higher demands for insulin.
Glucose Regulation:
What is involved?
Glucagon
Somatostatin
Pancreatic polypeptide
Glucose Regulation:
Glucagon: What does it do?
Elevates blood glucose levels to enable entry and use by cells of the body by stimulating the secretion of insulin
Glucose Regulation:
Somatostatin: What does it do?
Inhibits the release of insulin and glucagon from the pancreas
Glucose Regulation:
Pancreatic polypeptide:
Has a role in smooth muscle relaxation of the gallbladder
The Adrenal Glands:
What are the two parts?
Adrenal gland cortex
Medulla
The Adrenal Glands:
Adrenal gland cortex: What are the hormones produced by it?
- Mineralocorticoids
- Glucocorticoids
The Adrenal Glands:
Adrenal gland cortex:
Mineralocorticoids- What do they do?
Reabsorption of sodium
Elimination of potassium
The Adrenal Glands:
Adrenal gland cortex:
Glucocorticoids- What do they do?
Responds to stress
Decreases inflammation
Alters metabolism of protein and fat
The Adrenal Glands:
Medulla- produces what hormones?
Epinephrine
Norepinephrine
The Adrenal Glands:
Medulla-
Epinephrine- What does it do?
Stimulates sympathetic system
The Adrenal Glands:
Medulla-
Norepinephrine- What does it do?
Increases peripheral resistance
Endocrine Disorders:
Effect what parts of the body?
Affect all body systems
Endocrine Disorders:
What are they caused by?
Caused by an overproduction or an underproduction of hormones
Endocrine Disorders:
What are signs and symptoms?
Vital signs
Energy level
Fluid and electrolyte imbalances
Heat and cold intolerance
Weight changes
Altered sleep patterns
Thyroid Dysfunction:
What are the most common ones?
The most common are
hyperthyroidism,
hypothyroidism, and
thyroid nodules.
Thyroid Dysfunction:
Hyperthyroidism: its severe form?
Thyrotoxicosis (Thyrotoxic crisis)
Thyroid Dysfunction:
Hypothyroidism: its severe form?
Myxedema coma
Thyroid Dysfunction
What are causes of thyroid dysfunction?
Causes of thyroid dysfunction:
Graves’ disease,
Hashimoto’s disease,
thyroiditis.
Signs and Symptoms of Hypothyroidism:
Lower body:
Pretibial edema
Muscle weakness/cramps
Loss of body hair, dry patchy skin, cold intolerance
Menstrual irregularities
Signs and Symptoms of Hypothyroidism:
Middle body:
Constipation
Slower heart beat,
elevated cholesterol
Signs and Symptoms of Hypothyroidism:
Neck:
Swelling (goiter)
Hoarseness/deepening voice
Dry/sore throat
Difficulty swallowing
Signs and Symptoms of Hypothyroidism:
Head:
Thinning hair/hair loss
Puffy eyes
Signs and Symptoms of Hypothyroidism:
Mind:
Depression
Forgetfulness/slower thinking
Irritability
Inability to concentrate
Tiredness
Signs and Symptoms of Hyperthyroidism:
Lower body:
Osteoporosis
Infertility
Menstrual irregularities/light period
Excessive vomiting in pregnancy
First trimester miscarriage
Signs and Symptoms of Hyperthyroidism:
Middle body:
Warm moist palms
Fine tremors
Frequent bm
Weight loss
Signs and Symptoms of Hyperthyroidism:
Neck:
Hoarseness/deepening voice
Swelling (goiter)
Persistent dry or sore throat
Difficulty swallowing
Weight loss
Signs and Symptoms of Hyperthyroidism:
Head:
Heat intolerance
Increased sweating
Bulging eyes
Unblinking stare
Lid lag
Signs and Symptoms of Hyperthyroidism:
Mind:
Nervousness
Irritability
Difficulty sleeping
Normal Total T4 values
4-12 mcg/dL
Normal Free T4 values
0.8-2.7 ng/mL
Normal Free T4 index
4.6-12 ng/mL
Normal Free T3 index
260-480 pg/dL
Normal TSH values
260-480 pg/dL
Normal Total T4 values: 4-12 mcg/mL
What does a high T4 level indicate?
What does a low T4 level indicate?
High = hyperthyroidism
Low = hypothyroidism
Normal Free T4 values: 0.8-2.7 ng/mL
What does a high T4 level indicate?
What does a low T4 level indicate?
High in hyperthyroidism
Low in hyperthyroidism
Normal Free T3 values: 260-480 pg/dL
What does a high T3 level indicate?
What does a low T3 level indicate?
Low in hypothyroidism
Normal TSH values: 260-480 pg/dL
What does a high TSH level indicate?
What does a low TSH level indicate?
High in hypothyroidism
Low in hyperthyroidism
Thyrotoxic crisis (Thyroid storm)—
What is it?
Thyrotoxic crisis is a severe form of hyperthyroidism often associated with physiologic or psychological stress.
Thyrotoxic crisis (Thyroid storm)—
History and physical examination:
What are precipitating factors?
Precipitating factors such as infection, trauma, stress
Thyrotoxic crisis (Thyroid storm)—
History and physical examination:
What are meds are precipitating factors? Why?
Medications such as contrast material for radiographic procedures or amiodarone (an antiarrhythmic drug), may precipitate the thyrotoxic state because of their high iodine content.
Thyrotoxic crisis (Thyroid storm)—Assessment and management
What are signs and symptoms?
S & S:
Sweating,
heat intolerance,
nervousness/anxiety,
tremors,
palpitations,
tachycardia,
hyperkinesis (restlessness),
increased bowel sounds,
hyperthermia,
decreased LOC
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Labs: How are T3, T4 and TSH levels?
Elevated total T4, free T3, and free T4,
extremely low TSH
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Labs: How are electrolytes and more?
Hypercalcemia,
hyperglycemia,
abnormal LFTs,
high or low WBC
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management: What should be treated?
Treat the precipitating factor.
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management: What should be controlled?
Control excessive thyroid hormone release with Iodine solution
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management: What should be inhibited? how?
Inhibit thyroid hormone biosynthesis with antithyroid medications
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management: What else should be treated? What else should be given?
Treat the peripheral effects—nutritional support, manage hyperthermia
Medications
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management:
Medications: What is the preferred med during pregnancy? How is it given?
Antithyroid medication such as Propylthiouracil (PTU) is the preferred agent during pregnancy.
Only be given orally.
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management:
Medications: What other med can be given?
Iodine solutions or Lugol’s solution blocks release of thyroid hormone.
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management:
Medications: What is given for iodine sensitive patients?
Lithium for iodine sensitive patients.
Thyrotoxic crisis (Thyroid storm)—Assessment and management
Management: What is done for emergency removal of excess circulating hormone replacement?
Plasmapheresis, dialysis, or hemoperfusion adsorption for emergency removal of excess circulating hormone replacement.
Myxedema Coma;
What is it?
Rare, life-threatening emergency, extreme hypothyroidism
Myxedema Coma;
What is it precipitated by?
Precipitated by stress, extreme cold temperature, trauma
Myxedema Coma
Pathophysiology: Two types?
Primary
Secondary
Myxedema Coma
Pathophysiology
Primary:
loss of thyroid tissue, defective hormone synthesis, antithyroid drugs, iodine deficiency
Myxedema Coma
Pathophysiology
Secondary:
peripheral resistance to thyroid hormone, pituitary infarction, hypothalamic disorders
Myxedema Coma
Pathophysiology
Signs and symptoms
Fatigue, weakness, decreased bowel sounds, decreased appetite, weight gain, ECG changes
Altered mental status, hypothermia (no shivering), hypoventilation, hypoxemia, hyponatremia, hypoglycemia, hyporeflexia, hypotension, bradycardia
Myxedema Coma
Labs: T4? Na and K? TSH? ABGs?
Decrease T4 and free T4,
low sodium,
high potassium,
high TSH,
ABGs show severe hypercapnia with decreased arterial oxygen tension (PaO2) and increased arterial carbon dioxide tension (PaCO2).
Myxedema Coma—Management
Mechanical ventilation
IVF
Vasopressors
Thyroid hormone and corticosteroids
Rewarming
Monitor cardiovascular and respiratory function
Treat bowel symptoms
Patient education
Adrenal Gland Dysfunction—Adrenal Crisis
What is it also known as? How common is it?
Adrenal insufficiency is also known as Hypoadrenalism or hypocorticism
Rare but life threatening
Adrenal Gland Dysfunction—Adrenal Crisis
Primary adrenal insufficiency is called?
Addison’s disease
Adrenal Gland Dysfunction—Adrenal Crisis
H and P: What does Adrenal crisis effect?
Affects glucose metabolism, fluid and electrolyte balance, cognitive state, and cardiopulmonary status
Adrenal Gland Dysfunction—Adrenal Crisis
H and P: What are symptoms?
Weakness, fatigue, anorexia, nausea, vomiting, diarrhea, abdominal pain,
tachycardia, orthostatic hypotension, headache, dehydration, lethargy,
irritability
Adrenal Gland Dysfunction—Adrenal Crisis
Diagnostic studies: electrolytes?
Low sodium, high potassium, low serum bicarbonate, high BUN,
metabolic acidosis, hypoglycemia
Adrenal Gland Dysfunction—Adrenal Crisis
What confirms diagnosis?
Serum cortisol levels and cortisol stimulation confirm diagnosis.
Adrenal Crisis—Management
Hormone therapy
IVF (normal saline and 5% dextrose solutions)
Electrolyte balance
Prevent complications.
Monitor cardiovascular and respiratory status.
Monitor neuromuscular signs.
Emotional support
Patient education
Pheochromocytoma:
What is it?
Rare catecholamine-secreting tumor that arises from chromaffin cells (that produce and release epinephrine and norepinephrine) in the adrenal glands
Pheochromocytoma:
What occurs with it?
Life-threatening hypertension, cardiac dysrhythmia
Pheochromocytoma:
What is the triad?
Sudden and severe hypertension,
palpations,
sweating
Pheochromocytoma:
How is the diagnosis made?
Dx: measurement of fractionated plasma metanephrines and normetanephrines (blood test) and urine metanephrines and normetanephrines (urine test).
Pheochromocytoma:
How is the diagnosis confirmed?
Diagnosis is confirmed with MRI or CT
Pheochromocytoma:
How to treat?
Surgical resection of tumor, control hypertension
Antidiuretic Hormone Dysfunction:
What are the two types?
SIADH
Diabetes Insipidus (DI)
Antidiuretic Hormone Dysfunction:
SIADH: What is it?
Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is an excess of ADH.
Antidiuretic Hormone Dysfunction:
DI: What is it?
Diabetes insipidus (DI) involves a deficiency of ADH.
Antidiuretic Hormone Dysfunction:
SIADH and ADH: What can they both cause?
Both disorders can produce severe fluid and electrolyte imbalances and adverse neurologic changes.
Antidiuretic Hormone Dysfunction:
Pathophysiology SIADH: What is there an increase of?
Increased secretion or increased production of antidiuretic hormone (ADH)
Antidiuretic Hormone Dysfunction:
Pathophysiology SIADH: Increase of ADH causes what?
Increased ADH causes total increase in body water.
Antidiuretic Hormone Dysfunction:
Pathophysiology DI:
Water imbalance from inadequate or resistance to ADH
Antidiuretic Hormone Dysfunction:
Pathophysiology DI:
What happens normally (absence of DI)?
Normally as osmolality increases, hypothalamus releases ADH from the posterior pituitary, causing water and sodium absorption in the kidneys
Antidiuretic Hormone Dysfunction:
Pathophysiology DI:
Normally as osmolality increases, hypothalamus releases ADH from the posterior pituitary, causing water and sodium absorption in the kidneys. What happens in DI?
Normally as osmolality increases, hypothalamus releases ADH from the posterior pituitary, causing water and sodium absorption in the kidneys
Disruption in this process causes large volumes of dilute urine to be excreted.
SIADH—Assessment
What are possible causes of SIADH?
Possible causes of SIADH include pituitary tumor,
pancreatic carcinoma,
head injuries;
pulmonary diseases, such as pneumonia and lung abscesses;
CNS infections (meningitis) or tumor
SIADH—Assessment
History and physical examination
How are S and S?
S & S are neurologic and gastrointestinal
SIADH—Assessment
History and physical examination
What are signs and symptoms?
Headache, decreased mentation, lethargy, confusion, seizures, and coma
abdominal cramps, nausea, vomiting, diarrhea, anorexia
SIADH—Assessment
What are diagnostic studies showing?
Hyponatremia and hypo-osmolality,
high urine specific gravity,
low urine output,
low BUN and creatinine,
low calcium,
low potassium
SIADH—Management
What should be treated?
Treat underlying cause.
SIADH—Management
What should be alleviated?
Alleviate excessive water retention.
SIADH—Management
Alleviate excessive water retention.- How?
Fluid restriction,
3% hypertonic normal saline solution and
furosemide
SIADH—Management
What should be provided?
Provide comprehensive care needed for the patient with depressed LOC.
SIADH—Management
Provide comprehensive care needed for the patient with depressed LOC.
What should be monitored?
Monitor I & Os,
electrolytes,
neuro status.
Diabetes Insipidus—Assessment and MANAGEMENT
What is DI characterized by?
Diabetes insipidus is a disease characterized by water imbalance resulting from inadequate ADH or resistance to ADH, leading to water diuresis and dehydration.
Diabetes Insipidus—Assessment and MANAGEMENT
What are hallmarks of DI?
Polyuria, polydipsia, and dehydration are the hallmarks of diabetes insipidus.
Diabetes Insipidus—Assessment and MANAGEMENT
What are S and S of DI?
S & S of dehydration, tachycardia, hypotension, low central venous pressure (CVP), rise in body temperature, weight loss
Diabetes Insipidus—Assessment and MANAGEMENT
Management: What is given?
Hypotonic IVF
Desmopressin,
Pitressin,
permanent hormone replacement
Diabetes Insipidus—Assessment and MANAGEMENT
Management: What should be monitored?
Monitor fluid and electrolyte balance.
Diabetes Insipidus—Assessment and MANAGEMENT
What are complications?
Complications: cardiovascular collapse and tissue hypoxia
Laboratory Values for SIADH and Diabetes Insipidus
How is serum ADH in SIADH and DI?
SIADH: increased
DI: decreased
Laboratory Values for SIADH and Diabetes Insipidus
How is serum osmolality in SIADH and DI?
SIADH: <285
DI: >300
Laboratory Values for SIADH and Diabetes Insipidus
How is serum sodium in SIADH and DI?
SIADH: <33
DI: >145
Laboratory Values for SIADH and Diabetes Insipidus
How is urine osmolality in SIADH and DI?
SIADH: >300
DI: <300
Laboratory Values for SIADH and Diabetes Insipidus
How is urine output in SIADH and DI?
SIADH: below normal
DI: 30-40 L/24H
Laboratory Values for SIADH and Diabetes Insipidus
How is fluid intake in SIADH and DI?
SIADH: goal <600-800 mL/24h (restricted fluid intake)
DI: > 50L/24h
Diabetic Ketoacidosis
Pathophysiology
Severe insulin deficiency that leads to disordered metabolism of proteins, carbohydrates, and fats
Diabetic Ketoacidosis
Pathophysiology: What is there an elevation in?
Elevation in GH, cortisol, epinephrine, and glucagon exacerbates the condition.
Diabetic Ketoacidosis
What occurs in this?
Ketosis and acidosis
Volume depletion
Diabetic Ketoacidosis
Who does it occur in mostly?
Mostly occurs in type I diabetics
Diabetic Ketoacidosis
What are causes of this?
Causes: infection,
inadequate insulin therapy,
severe illness,
stroke,
MI,
pancreatitis,
alcohol abuse,
trauma,
drugs
Diabetic Ketoacidosis—Assessment
History and physical examination:
What should be collected?
Detailed history,
focus on diabetic regimen and compliance,
recent changes in health,
appetite, weight,
abdominal bloating,
bowel function,
urinary frequency and amount.
Diabetic Ketoacidosis—Assessment
History and physical examination:
What VS should be assessed?
Blood pressure,
heart and respiratory rate,
breathing pattern,
breath sounds, LOC
Diabetic Ketoacidosis—Assessment
History and physical examination: What is seen?
Findings:
hyperventilation,
Kussmaul’s respiration,
fruity breath,
dehydration,
abdominal distention,
dry mucous membranes,
poor skin turgor,
decreased LOC
Diabetic Ketoacidosis—Assessment & MANAGEMENT
Laboratory studies: What kind of labs are collected?
Glucose,
electrolytes,
osmolality,
anion gap,
pH,
ABGs,
urine acetone,
Diabetic Ketoacidosis—Assessment & MANAGEMENT
Laboratory studies: How are glucose ranges?
Serum glucose ranges from 250 mg/dL to 800 mg/dL or higher.
Diabetic Ketoacidosis—Assessment & MANAGEMENT
Laboratory studies: What is a key diagnostic feature?
Serum ketones is key diagnostic feature.
Diabetic Ketoacidosis—Assessment & MANAGEMENT
Diagnostic studies:
Urine test, blood glucose.
Throat, blood, and urine cultures may be done to rule out infection
Diabetic Ketoacidosis—Assessment & MANAGEMENT
What is included in management?
Fluid replacement
Insulin therapy
Potassium and phosphate replacement
Bicarbonate replacement
Reestablishing metabolic function
Patient education
if you have time- slides 29-32
