Nursing Assessment: Endocrine System J. Brinley, MSN, RN, CNE

Structures and Functions of Endocrine System 2 Fig Location of the major endocrine glands. The parathyroid glands lie on the posterior surface of the thyroid.

Structures and Functions of Endocrine System Glands Hormones – Classifications and functions – Hormone transport – Targets and receptors 3

Hormone Functions and Regulation Released in response to body ’ s needs Responsible for reproduction, fluid and electrolyte balance, host defenses, responses to stress and injury, energy metabolism, and growth and development Endocrine system: maintain homeostasis – Maintenance of physiologic stability despite constant changes in the environment

Structures and Functions of Endocrine System Hormones – Targets and receptors, continued Steroid hormone receptors 5

Structures and Functions of Endocrine System 6 Fig The target cell concept. Hormones act only on cells that have receptors specific to that hormone, because the shape of the receptor determines which hormone can react with it. This is an example of the lock-and-key model of biochemical reactions.

Structures and Functions of Endocrine System 7 Fig A, Protein hormones bind to receptors located in the cell membrane. The hormone-receptor interaction stimulates the formation of cAMP, thereby activating various cell processes. B, Steroid hormones penetrate the cell membrane and interact with intracellular receptors. The hormone-receptor complex activates the cell by stimulating protein synthesis.

Structures and Functions of Endocrine System Hormones – Targets and receptors, continued Protein hormone receptors 8

Structures and Functions of Endocrine System Hormones, continued – Regulation of hormonal secretion Simple feedback 9

Structures and Functions of Endocrine System 10 Fig Feedback mechanism between blood glucose and insulin. A, Increased blood glucose stimulates increased insulin secretion from the pancreas. B, As blood glucose levels decline, insulin secretion decreases.

Structures and Functions of Endocrine System 11 Fig Feedback mechanism between parathyroid hormone (PTH) and calcium.

Structures and Functions of Endocrine System Hormones – Regulation of hormonal secretion, continued Complex feedback 12

Structures and Functions of Endocrine System 13 Fig General model for control and negative feedback to hypothalamus-pituitary target organ systems. Negative feedback regulation is possible at three levels: target organ (ultrashort feedback), anterior pituitary (short feedback), and hypothalamus (long feedback).

Structures and Functions of Endocrine System Hormones – Regulation of hormonal secretion, continued Nervous system control Rhythms 14

Structures and Functions of Endocrine System 15 Fig Circadian rhythm of cortisol secretion.

Structures and Functions of Endocrine System Hypothalamus 16

Test your knowledge Two hormones produced by the posterior pituitary gland (neurohypophysis) are: a.Antidiuretic hormone (ADH) and oxytocin. b.Growth hormone (GH) and adrenocorticotropic hormone (ACTH). c.Thyroid-stimulating hormone (TSH) and growth hormone (GH). d.Follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Answer A antidiuretic hormone (ADH) and oxytocin.

Structures and Functions of Endocrine System 19 Table Hormones of the Hypothalamus.

Anatomy and Physiology Anterior lobe – Larger of the two lobes: accounts for 70% to 80% of the gland ’ s weight – Called the adenohypophysis – Secretes Growth hormone (GH), or somatotropic hormone Adrenocorticotropic hormone (ACTH) Thyroid-stimulating hormone or thyrotropic hormone Follicle-stimulating hormone Luteinizing hormone Prolactin, or lactogenic hormone Melanocyte-stimulating hormone

Structures and Functions of Endocrine System 21 Fig Relationship between the hypothalamus, pituitary, and target organs. The hypothalamus communicates with the anterior pituitary via a capillary system and with the posterior pituitary via nerve tracts. The anterior and posterior pituitary hormones are shown with their target tissues.

Structures and Functions of Endocrine System Pituitary – Anterior pituitary, continued Tropic hormones Growth hormone Prolactin – Posterior pituitary Antidiuretic hormone 22

Structures and Functions of Endocrine System 23 Table Factors Affecting ADH Release.

Structures and Functions of Endocrine System 24 Fig Relationship of plasma osmolality to antidiuretic hormone (ADH) release and action.

Structures and Functions of Endocrine System Pituitary – Posterior pituitary, continued Oxytocin 25

Structures and Functions of Endocrine System 26

Structures and Functions of Endocrine System 27 Fig Thyroid and parathyroid glands. Note the surrounding structures.

Structures and Functions of Endocrine System Thyroid Gland, continued – Thyroxine and triiodothyronine – Calcitonin Parathyroid Glands – Parathyroid hormone 28

Structures and Functions of Endocrine System Adrenal Glands 29

Structures and Functions of Endocrine System 30 Fig The adrenal gland is composed of the adrenal cortex and the adrenal medulla.

Structures and Functions of Endocrine System Adrenal Glands, continued – Adrenal medulla – Adrenal cortex Cortisol Aldosterone Adrenal androgens Pancreas – Glucagon – Insulin 31

Structures and Functions of Endocrine System 32 Table Factors Influencing Insulin Secretion.

Gerontologic Considerations: Effects of Aging on Endocrine System Some subtle and come obvious changes Decreased hormone production and secretion Altered hormone metabolism and biologic activity Decreased responsiveness of target tissues to hormones Alterations in circadian rhythms Review table 48-5 on page

Assessment of Endocrine System Subjective Data – Important health information Past health history including growth and development Medications – OTC, herbs, and dietary supplements – HRT » Insulin, thyroid hormones, corticosteroids Surgery or other treatments – Chemotherapy, radiation, brain surgery or head injury 34

Assessment of Endocrine System Subjective Data, continued – Functional health patterns Health perception–health management pattern Nutritional-metabolic pattern Elimination pattern Activity-exercise pattern Sleep-rest pattern Cognitive-perceptual pattern 35

Assessment of Endocrine System Subjective Data – Functional health patterns, continued Self perception–self-concept pattern Role-relationship pattern Sexuality-reproductive pattern Coping–stress tolerance pattern Value-belief pattern 36

Assessment of Endocrine System Objective Data – Physical examination Vital signs Height and weight Mental-emotional status Integument Head Neck 37

Assessment of Endocrine System 38 Fig Posterior palpation of the thyroid gland.

Assessment of Endocrine System Objective Data – Physical examination, continued Thorax Abdomen Extremities Genitalia 39

Diagnostic Studies of Endocrine System Laboratory Studies – Pituitary studies GH Water deprivation (ADH stimulating) – Thyroid studies TSH, T3 and T4, Thyroid antibodies – Parathyroid studies PTH, Calcium, Phosphate – Adrenal studies Cortisol, Aldosterone, ACTH, dexamethasone suppression 24hour urine 17ketosteroids CT and MRI – Pancreatic studies OGTT, HbA1C 40