Endocrine System Part 1 PDF

ENDOCRINE SYSTEM Part I DR. SOHEIR TAWFEEK SHAHEEN PRO F. O F M EDI CAL S U RGICAL N U RSING At the end of lecture the learner will be able to: 1. Describe the common characteristics and functions of hormones. 2. Identify the locations of the endocrine glands. 3. Describe the functions o...

ENDOCRINE SYSTEM Part I DR. SOHEIR TAWFEEK SHAHEEN PRO F. O F M EDI CAL S U RGICAL N U RSING At the end of lecture the learner will be able to: 1. Describe the common characteristics and functions of hormones. 2. Identify the locations of the endocrine glands. 3. Describe the functions of hormones. 4. Select the significant subjective and objective assessment data related to the endocrine system. 5. Differentiate normal from common abnormal findings of a physical assessment of the endocrine system. Endocrine system: Acts with nervous system as the body’s communication network. It is consists of various endocrine glands that are capable of synthetizing and releasing special chemical substances (hormones) such as hypothalamus, pituitary, thyroid, para-thyroids, adrenals, pancreas, ovaries, testes, and pineal gland Exocrine glands. They secrete their substances into ducts that then empty into a body cavity or onto a surface. For example, salivary glands produce saliva, which is secreted through salivary ducts into the mouth. Hormones: It’s a chemical substances produced in the body that control and regulate the activity of certain target cells or organs. Many are produced in one part of the body and control and regulate the activity of certain cells or organs in another part of the body. Endocrine glands produce and secrete hormones that travel to affect their specific target tissues. For example, the thyroid gland synthesizes the hormone thyroxine, which affects all body tissues. Some hormones are released directly into the circulation such as pituitary, thalamus, thyroid , parathyroid , thymus , adrenals and pancreas ,endocrine glands release hormones directly into the blood stream. These glands have no ducts (ductless glands) to release hormones produced by them. whereas others may act locally on cells where they are released and never enter the bloodstream. This local effect is called paracrine action. An example, is the chemical transmitted from nerve to muscle that causes the muscle to contract Most hormones have common characteristics including: (1) Secretion in small amounts at variable but predictable rates (2) Regulation by feedback systems. (3) Binding to specific target cell receptors. Hormone Receptors. Hormones exert their effects by recognizing their target tissues and attaching to receptor sites in a “lock-and-key” type of mechanism. Therefore a hormone will act only on cells that have a receptor specific for that hormone Lipid-Soluble and Water-Soluble Hormones. Hormones are classified by their chemical structure as either lipid soluble or water soluble. The differences in solubility become important in understanding how the hormone interacts with the target cell. Water-soluble hormones (insulin, growth hormone [GH], and prolactin) have receptors on or in the cell membrane. Water-soluble hormones circulate freely in the blood to their target tissues, where they act. Water-soluble hormones are not dependent on plasma proteins for transport Lipid-soluble hormones are synthesized from cholesterol and are produced by the adrenal cortex, sex glands, and thyroid. Lipid-soluble hormones (steroids, thyroid) are relatively small molecules that cross the target cell membrane by simple diffusion. Lipid- soluble hormones are bound to plasma proteins for transport in the blood Regulation of Hormonal Secretion The regulation of endocrine activity is controlled by specific mechanisms of varying levels of complexity. These mechanisms stimulate or inhibit hormone synthesis and secretion and include feedback, nervous system control, and physiologic rhythms Endocrine system ASSESSMENT OF ENDOCRINE SYSTEM Endocrine dysfunction may be the result of hypersecretion or hyposecretion of hormones. The onset of symptoms for specific disorders may be insidious and produce subtle or vague symptoms that are attributed to other physiologic and psychologic causes Subjective Data A- HEALTH HISTORY Information obtained from the patient can provide important clues as to the functioning of the endocrine system. Obtain a thorough history from the patient or a family member if the patient’s mental acuity is compromised. Used the Gordon’s Functional Health Patterns Gordon’s Functional Health Patterns focused on: Nutritional-Metabolic Pattern (questions for the example) What is your weight and height? Have there been any changes in your appetite or weight? Have you noticed any changes in the distribution of the hair anywhere on your body? Have you noticed any changes in the color of your skin, particularly on your face, neck, hands, or body creases? Have you noticed any difficulty swallowing, throat pain, or hoarseness? Elimination Pattern Do you have to get up at night to urinate? Have you ever had a kidney stone? Describe your usual bowel pattern. Have you noted any bowel changes? Do you use anything, such as laxatives, to help you move your bowels? Sleep-Rest Pattern How many hours do you sleep at night? Do you feel rested on awakening? Are you ever awakened by sweating during the night? Do you have nightmares? Activity-Exercise Pattern Do you experience fatigue with or without activity? Have you had any trouble with breathing? What is your usual activity pattern during a typical day? Cognitive-Perceptual How is your memory? Have you noticed any changes? Have you experienced any blurring or double vision? When was your last eye examination? Sexuality-Reproductive Pattern Women When did you start and last to menstrual period? Are you menopause? Were you told you had diabetes during any pregnancy? Men Have you noticed any changes in your ability to have an erection? Are you trying to have children but cannot? Self-Perception–Self-Concept Have you noticed any changes in your physical appearance or size? Are you concerned about your weight? Role-Relationship Are you married? Do you think you are able to take care of your family and home? Are you able to do what is expected of you and what you expect of yourself? How do you spend your time now that you’ve retired? B-Family History and Genetic Risk C- Current Health Problems D- Medications. Ask about the use of all medications (both prescription and over-the-counter drugs). Ask about the reason for taking the drug, the dosage, and the length of time the drug has been taken.  Objective Data I- Diagnostic studies: Check the following laboratory results for critical values. Potassium Glucose Sodium Glycosylated hemoglobin (Hb A1C) Thyroid studies: TSH, T3, T4  II- PHYSICAL ASSESSMENT Inspect/Measure (use a head-to-toe approach to inspect any physical change). Body temperature Height and weight Alertness and emotional state Skin for changes in color and texture Hair for changes in color, texture, and distribution Palpate Extremities for edema Skin for texture and temperature Neck for thyroid size, shape Auscultation (chest-pulse – B.p)  III- DIAGNOSTIC TESTS I- Hormone Tests Serum Hormone Levels Stimulation Tests Suppression Tests 2- Urine Tests 3- Other Laboratory Tests Reflect the function of an endocrine gland. For example, a serum calcium and blood glucose level.  DIAGNOSTIC TESTS Cont. 4- Nuclear Scanning Radioactive iodine is taken orally; after a specified time, the scanned with a scintillation camera. 5- Radiographic Tests CT scan or (MRI) may be done to locate a tumor or identify hypertrophy of a gland. 6- Ultrasound Ultrasound may be done to determine enlarged or to find masses 7- Biopsy Biopsy is done to obtain tissue to examine for possible cancerous cells Pituitary Gland The pituitary gland is suspended by a short stalk from the hypothalamus in the brain. The two major regions are: The Posterior pituitary gland Its store and release 2 hormones; ADH and Oxytocin, which are actually produced by the hypothalamus and transported along nerve axons to the posterior pituitary Anterior Pituitary gland The anterior pituitary gland is larger than posterior gland its synthesizes and secretes growth hormone, thyroid-stimulating hormone, adrenocorticotropic hormone, prolactin, follicle-stimulating hormone, and luteinizing hormone  ENDOCRINE’S HERMONS FUNCTION Hormone Function(s) Regulation of Secretion Hormones of the Posterior Pituitary Gland Oxytocin Promotes contraction of Nerve impulses from myometrium of uterus (labor) hypothalamus, the result of Promotes release of milk from stretching of cervix or stimulation mammary glands of nipple Secretion from placenta at the end of gestation— stimulus unknown Antidiuretic Increases water reabsorption Decreased water content in the hormone (ADH) by the kidney tubules (water body (alcohol inhibits secretion) returns to the blood  ENDOCRINE’S HERMONS FUNCTION Hormone Function(s) Regulation of Secretion Hormones of the Anterior Pituitary Gland Growth hormone Increases rate of mitosis Growth hormone-releasing hormone (GH) Increases amino acid transport (GHRH) is a neuropeptide secreted by into cells the hypothalamus that stimulates the Increases rate of protein synthesis synthesis and release of growth Increases use of fats for energy hormone (GH) in the pituitary Thyroid-stimulating Increases secretion of thyroxine Thyrotropin-releasing hormone hormone (TSH) and T3 by thyroid gland (TRH), is a hypophysiotropic hormone, produced by neurons in the hypothalamus, that stimulates the release of thyroid-stimulating hormone (TSH) and prolactin from the anterior pituitary. Adrenocorticotropic Increases secretion of cortisol by Corticotropin-releasing hormone (ACTH) the adrenal cortex hormone (CRH) is a peptide hormone involved in the stress response. It is a releasing hormone that belongs to  Hormone Function(s) Regulation of Secretion Prolactin Stimulates milk production by the Pregnancy-induced hypertension (PIH) is mammary glands the development of new hypertension in a pregnant woman after 20 weeks' gestation without the presence of protein in the urine or other signs of pre-eclampsia. Follicle- In women: Gonadotropin-releasing hormone GnRH stimulating Initiates growth of ova in ovarian follicles Is a tropic peptide hormone synthesized and hormone (FSH) Increases secretion of estrogen by follicle released from neurons within the Cells hypothalamus. In men: Inhibits secretion of ovaries or testes Initiates sperm production in the testes Luteinizing In women: hormone -Causes ovulation (LH) -Causes the ruptured ovarian follicle to become the corpus luteum -Increases secretion of progesterone by the corpus luteum In men: -Increases secretion of testosterone by the interstitial cells of the testes  Thyroid Gland The thyroid gland consists of two lobes and is located on the front and sides of the trachea just below the larynx. Three hormones are produced by the thyroid gland. T4 and T3, T4 and Calcitonin. The mainly function of thyroid hormones are carbohydrate metabolism, fat metabolism, basal metabolic rate, body weight and sexual function.  Parathyroid Glands There are usually four parathyroid glands, two on the back of each lobe of the thyroid gland. The hormone they produce called parathyroid hormone (PTH), which is an antagonist to calcitonin; it maintains and regulate normal blood levels of calcium and phosphate.. Adrenal Glands The two adrenal (also called suprarenal) glands are located one on top of each kidney. Each adrenal gland consists of an inner adrenal medulla and an outer adrenal cortex. It is secreted Aldosterone and Glucocorticoids hormones. Pancreas The pancreas extends from the curve of the duodenum to the spleen. The endocrine portions of the pancreas are called islets of Langerhans (pancreatic islets); they contain alpha cells, which produce glucagon, and beta cells, which produce insulin.  THANK YOU Will be continue in part II