Endocrine Lecture Notes PDF 2024 - Flinders University

Endocrine disorders PARA2003 Pathophysiology 2B  Learning outcomes Describe the general function and physiology of the endocrine system Identify the role of: the pituitary gland in homeostasis the thyroid gland in maintaining metabolic rate the...

Endocrine disorders PARA2003 Pathophysiology 2B  Learning outcomes Describe the general function and physiology of the endocrine system Identify the role of: the pituitary gland in homeostasis the thyroid gland in maintaining metabolic rate the adrenal gland in the stress response and fluid/electrolyte balance Describe the major disorders of the pituitary, thyroid and adrenal glands and their effects Outline the implications of endocrine disorders on paramedic practice LO1: Apply an integrated understanding of the anatomy and physiology of body systems to paramedic practice LO5: Apply an understanding of endocrine pathophysiology to provide effective management and support for patients with diabetes and other endocrine emergencies This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Lecture Outline 1. General function and physiology of the endocrine system as a whole 2. The role of the pituitary gland in homeostasis, significant pituitary disorders and the implications for paramedic practice 3. The role of the thyroid gland in homeostasis and metabolism, significant thyroid disorders and the implications for paramedic practice 4. The role of the adrenal gland in the stress response and fluid/electrolyte balance, significant adrenal disorders, and the implications for paramedic practice Note: Diabetes is an endocrine disorder so significant for medicine that it is often considered on its own (lectures specifically about diabetes to come). This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Getting the most from this lecture I will try to highlight some very important ideas as key concepts, and provide some high yield information. I have structured this lecture based on each key learning outcome, with a few quick questions to check you have understood those key concepts – stop the lecture to do these as this is the best way to consolidate knowledge. I try to talk slowly but clearly. If this is too slow for you, I won't be offended if you speed it up. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. General function and physiology of the endocrine system as a whole This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Organisation of the Endocrine System Collection of glands, scattered throughout the body Not structurally connected – linked through a shared signaling mechanism: Hormones Hormonal signaling = secretion of chemicals into the bloodstream to act on distant targets (called endocrine hormones) Hormones can also be called: Autocrine hormones: acting on the cell that secreted them. Paracrine hormones: acting on neighboring cells in the environment. Sherwood, This material has been reproduced and communicated to you by or on behalf of Flinders University in Lauralee, Accordance withand Kristen section Sutton. 113P of the CopyrightHuman Physiology Act 1968 (the : From Act). The material in this Cells to Systems, Cengage Learning, 2015 communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hormone secretion and circulation Endocrine glands secrete hormones after a stimuli Neural signal (eg. Adrenaline) Mechanical / functional signal (eg. Renin) Hormonal signal (eg. Pituitary hormones) Hormones travel in the circulation in incredibly low concentrations (for some, as little as a picogram – millionth of a millionth of a gram) Key Concept: effects are proportional to the concentration Concentration depends on rate of secretion, metabolism, and removal/excretion Concentration is tightly regulated, normally thorough negative feedback https://flexbooks.ck12.org/cbook/ck-12-biology-flexbook- 2.0/section/13.22/primary/lesson/hormone-regulation-bio. n.b there is also positive feedback This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  How do hormones have an effect on tissue? Hormones achieve effect by their actions on target receptors that are present on certain cells. Key Concept: Action of the hormone actually depends on the receptor, not the hormone itself Receptors act through secondary messenger signaling to alter cell functions Familiar example: Adrenaline A1 receptors in smooth muscle – constriction B2 receptors in smooth muscle – dilation B1 receptors in heart – inotropy, chronotropy etc. Alteration in receptor function can therefore change effect Cells may up- or down- regulate # receptors or receptor responses over time Receptors make very good targets for pharmaceuticals This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Receptor activation: Cell membrane example Receptors do not influence cell in their inactive state Hormone binding activates the receptor, in this case activates G-protein G protein detaches and acts on a downstream target, triggering a secondary messenger cascade to cause Note: Receptors can be intercellular, have different mechanisms – but 2nd messenger theme similar Hall J., H. M. (2021). Guyton and Hall Textbook of Medical Physiology (14th Ed). Philadelphia: Elsevier. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Systemic functions of the endocrine system Metabolism Homeostasis (constant internal balance), such as blood pressure and blood sugar regulation, fluid (water) and electrolyte balance and body temperature. Growth and development. Sexual function. Reproduction. Sleep-wake cycle. Mood, Stress. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Basis of endocrine diseases As blood concentration of hormones is the key determinant of effect, loss of normal regulation is the most common cause of disease. Hypersecretion: beyond body needs Hyposecretion: below body needs May also be due to dysfunctional clearance or tissue response (eg. Diabetes – may be secondary outcome of other diseases ie. cancer cells and tumors). Feather A, R. D., Waterhouse M. (2021). Kumar and Clark's Clinical Medicine (10th Edition ed.). London: Elsevier. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Common pathological causes of endocrine disease Tumour / mass eg. Pituitary tumour = hypersecretion Trauma / tissue destruction = hyposecretion Infarction eg. Adrenal infarction = hyposecretion Infection e.g pancreatitis = insulin insufficiency Iatrogenic eg. Steroid therapy  Addisons Disease Congenital Idiopathic eg. ???? Sometimes bad just happens This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  1. Describe the organisation 2. Identify the key Learning of the endocrine system and determinant of hormone define primary and secondary effects and list the factors by endocrine organs which this is regulated Check 1: Can you… 3. Describe the mechanisms 4. List some drugs that of hormone action on tissues. harness the mechanisms of Provide an example of a single hormone action to achieve a hormone with different pharmacological effect effects in different tissues 5. Outline the general ways that the endocrine system can become disturbed in disease, and some underlying pathological causes This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  The role of the pituitary gland in homeostasis, significant pituitary disorders and the implications for paramedic practice This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypothalamus and pituitary gland “Conductor of the endocrine orchestra” Located in the pituitary fossa at the base of the brain, around the third ventricle Connected directly to the hypothalamus by the ‘stalk’ Interfaces between brain and bloodstream This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Hypothalamus and pituitary gland “Conductor of the endocrine orchestra” Two functionally separate halves Anterior pituitary = glandular Posterior pituitary = neural Operation of both coordinated by the hypothalamus via stalk This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Anterior pituitary: Glandular Tissue Connected to the hypothalamus by a portal system of vessels Neurons of the hypothalamus secrete pituitary releasing hormones into the portal system  trigger release of pituitary hormones into systemic circulation These may have primary effects, or may act on other endocrine organs Key concept: Hypothalamic-Pituitary-XXX axis (eg. H-P-Adrenal, H-P-thyroid axis) Complex, interrelated way that theses hormones are regulated in the body Disturbance of these axis crucial in many disease states http://www.pharmacy180.com/article/pituitary-gland-3595/ This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Anterior pituitary: Functions Growth hormone: + growth throughout body. Protein synthesis, cell replication. Gonadal hormones (LH & FSH): regulates reproductive and secretory functions Thyroid-stimulating hormone: Acts on thyroid to regulate secretion Adrenocorticotropic hormone: Acts on adrenal cortex to regulate secretion Prolactin: Acts on mammary glands This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Posterior pituitary: Neural tissue Paraventricular Direct projections of nucleus Neurosecretory hypothalamic neurons neurons hormones Hypothalamus down the stalk synthesized in cell body Secrete two key hormones Supraoptic directly into the systemic = Vasopressin (ADH) circulation = Oxytocin nucleus Neuron axons Antidiuretic Hormone Anterior Posterior pituitary (ADH) pituitary Systemic AKA Vasopressin arterial inflow Systemic Oxytocin venous outflow delivers hormones to target and This material has been reproduced tissue communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  “Conductor of the endocrine orchestra” This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Fluid homeostasis – ADH (ADH = vasopressin) This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Anti-diuretic hormone (ADH) / vasopressin regulates fluid levels ↓ blood volume = hypovolaemia (dehydration, blood loss etc) Reduced blood volume = Increased plasma osmolarity (↑ concentration of solutes) ADH released by the p. pituitary in response to decreasing plasma fluid levels Acts primarily on kidneys – implants water pores in the renal tubules causing reabsorption of water This restores blood volume Feather A, Randall D, Waterhouse M. (2021). Kumar and Clark's Clinical Medicine (10th Edition ed.). London: Elsevier. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Diabetes Insipidus Disorder characterised by loss of ADH effect hypothalamic/pituitary disease (neurogenic) – most commonly surgery and cranial pathology renal disease (nephrogenic) (gestational and polydipsia) Unable to retain water at kidneys Severe dehydration and hypernatraemia Completely different to Diabetes Mellitus (probably originally put together due to polyuria) Fun fact: Alcohol blocks the production / secretion of ADH – inhibiting renal water retention leading to polyuria and dehydration This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Diabetes Insipidus Clinical Findings Hx: extreme polyuria (can be 10-15L / day) and polydipsia Biochem: hypernatraemia, low specific gravity urine ?Recent cranial surgery or pathology Clinical impression of severe dehydration May have hypovolaemic shock This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Rare presentation - may complicate other presentations Diabetes insipidus: Important differential in dehydration Paramedic with normal glucose practice Need heavy but careful fluid resuscitation – monitoring hourly electrolytes and ongoing care. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  ADH hypersecretion Excessive secretion Syndrome of inappropriate ADH secretion (SIADH) Distorted fluid balance, retaining too much water Often due to cancer (& some drugs) Causes oedema and hyponaturaemia. Clinical Presentation: - N+V - Confusion/altered mentation - Seizures This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Posterior pituitary hormones - Oxytocin An example of positive feed-back loop (stopped by removal Oxytocin analogue; of the stimulus) syntocinon used to manage post-partum haemorrhage in out-of- hospital childbirth This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Anterior pituitary hormones This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypopituitarism Hyperpituitarism Loss of secretory Excessive secretion function Generally due to Infarction of pituitary secretory tumour Non-functional cancer Or hypothalamic / mass disorder Trauma Infection or inflammation This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypopituitarism: Growth hormone Pituitary dwarfism Stunted growth Delayed maturation Neuro- developmental delay Hypoglycaemic episodes Kiran Shah Treated with HRT Actor and stuntman This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hyperpituitarism: Growth hormone Before skeletal maturity: Gigantism Excessive height/weight Excessive bone growth Characteristic features Spinal problems Joint problems Enlarged heart - HF Hyperglycaemia Late onset: Acromegaly Enlargement of hands, nose, tongue, jaw Suspicious for hypersecretory pituitary tumour Suggests internal changes Robert Wadlow 8ft11 1918 – 1940 – 22 yrs Pituitary hypertrophy This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Go Look For The Adenoma Please Anterior Pituitary Hormones Pituitary Adenoma will effect all of these This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Describe the dual structure of the pituitary Describe gland and relation to other structures Explain the meaning of the hypothalamic- Explain pituitary axis in hormone secretion Learning Check 2: Can you… Outline the role of the posterior pituitary in Outline fluid balance and how this may go wrong Provide an example of the causes and Provide consequences of hyper or hypopituitarism This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. The role of the thyroid gland in homeostasis and metabolism, significant thyroid disorders and the implications for paramedic practice This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Thyroid gland The ‘thyroid axis’ (H-P-T) controls the basal metabolism of virtually all nucleated cells Thyroid disorders are the most common of all endocrine disorders Two Thyroid hormones Thyroxine (T4) Triidothyronine (T3) This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Thyroxine (T4) + Triidothyroxine (T3) The ‘thyroid axis’ (H-P-T) controls the basal metabolism of virtually all nucleated cells, dictating baseline rates of Mitochondrial activity – ATP generation and O2 consumption Glucose utilisation Lipolysis Protein catabolism Also (positively) affect growth, CNS, CVS etc. Iodine required for synthesis – iodine deficiency a large cause of morbidity worldwide Hall J., H. M. (2021). Guyton and Hall Textbook of Medical Physiology (14th Ed). This material has been reproduced and communicated to you by or on behalf of Flinders University Philadelphia: in Accordance Elsevier. with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Hypothyroidism - Causes Hypometabolic state caused by diminished circulating thyroid hormones Very common in the community – heard of levothyroxine? May be primary or secondary causes Autoimmune dysfunction (Hashimotos) Thyroiditis Damage from surgery, radioiodine therapy or radiation Iodine deficiency Pituitary / hypothalamic disease -  TSH This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypothyroidism – Clinical Features Generally decreased metabolism: characteristic symptoms include: Low energy, enthusiasm, apathy Weight gain Deep voice Dry, thick skin & sparse hair Worsened cold intolerance Constipation Bradycardia Oligomnorrrea Slowed mentation May be associated with low mood, mental health problems, depression This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypothyroidism – Treatment Core therapy is levothyroxine (hormone replacement therapy) A very common medication to encounter in the community Appreciate the effects that this disorder / insufficient HRT has on your patient’s metabolism, weight, mood etc. Consider how this influences other conditions or contributes comorbidity Myxoedema Coma Terminal phase of decompensated hypothyroidism Rare in hyposecretion, mainly consider in post surgery, injury, complete thyroidectomy etc Altered mental state, coma, hypothyroidism Rare to see in practice but good to know. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Hypersecretion: Thyrotoxicosis Hypermetablic state caused by excessive circulating thyroid hormones Graves Disease (most common) Autoimmune disorder: own antibodies act on TSH receptor causing own unregulated release of T4 Thyroid becomes enlarged (goitre) and overactive Tumour – pituitary or thyroid Thyroiditis Thyroxine overdose (intentional or unintentional) This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Thyrotoxicosis – Clinical Features Increased metabolic rate Tachycardia, atrial fibrillation Nervousness, agitation & insomnia Opthalmopathy Heightened stress response Marty Feldman - Actor Tremors 1934 -1982 ↑ appetite with loss of weight Warm, sweaty skin & heat Intolerance Malaise & muscle weakness Diarrhoea Goitre – enlarged thyroid This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Thyrotoxicosis - Treatment Drugs to suppress thyroxin release (eg Carbimazole) Can cause liver dysfunction & teratogenetic Propanolol (suppress SNS symptoms) Symptomatic control only Radioactive iodine ablation Produces a secondary hypothyroidism – needs levothyroxine Partial or total thyroidectomy Produces a secondary hypothyroidism – needs levothyroxine This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Thyroid Crisis (Storm) Rare life threatening extreme of thyrotoxicosis – may be secondary to trauma (surgery) Fever Tachycardia+++ and heart failure Seizures Delirium, psychosis or coma This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Thyroid storm Recognise as a differential for patients with agitation, delirium, sympathetic overdrive (hot, sweaty, agitated, tachycardic) Particularly if recent thyroid treatment Cool Check BGL IV glucose IV Hydrocortisone This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Parathyroid glands Control plasma calcium levels through parathyroid hormone and calcitonin Parathyroid hormone increases plasma calcium increases bone resorption by osteoclasts increases renal reabsorption increases intestinal absorption (via stimulation of calcitriol [vitamin D3] synthesis) Calcitonin decreases plasma calcium – “tones down calcium” Opposite effects to PTH on bone resorption and renal reabsorption Disorders can create risk of pathological fractures Can be a target for osteoporosis treatment This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypercalcaemia (too much calcium) Parathyroid gland dysfunction Clinical Presentation: - “bones, stones, groans & psychiatric moans” This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Name the thyroid hormones and outline their key effects Learning Check 3: Can Describe the control of thyroid hormone release and describe the consequences of hypo you… / hyper secretion Outline the major clinical findings in thyroid disorders and the implications in paramedic practice Outline the role of the parathyroid glands and consider the context of dysfunction This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  The role of the adrenal gland in the stress response and fluid/electrolyte balance, significant adrenal disorders, and the implications for paramedic practice This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  The adrenal gland Located above the kidneys (“ad-renal”) Own artery and vein – secretes directly into circulation (functions independent of kidney) Structurally comprises of inner medulla and outer cortex Outer cortex Synthesises aldosterone and Acland, R (2021). Acland’s Video Atlas of Human Anatomy. glucocorticoids Wolters Kluwer https://aclandanatomy.com/ Inner medulla - structurally and functionally distinct, develops from neural cells in utero. Synthesises and secretes catecholamines We will not cover this section Kumar and Clark's Clinical Medicine (10th Edition ed.) 2021 This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with London: section Elsevier. 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Adrenocortical hormones The adrenal cortex synthesises and secretes ‘steroid hormones’ from cholesterol. More than 30 are known, but key ones are: Minderalocorticoids: Aldosterone (salty) Glucocorticoids: Cortisol (sweet) Androgens: Testosterone, Estrogen (sex) This is the origin of the terms ‘corticosteroids’ This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Mineralocorticoids - Aldosterone Key player in fluid homeostasis, in concert with the rest of the renin- angiotensin-aldosterone system (RAAS) Functions primarily to influence Na+ retention and K+ loss in the renal tubules By increasing retention of Na+, causes retention of H2O https://teachmephysiology.com/urinary-system/regulation/the-renin-angiotensin- aldosterone-system/ This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Glucocorticoids - Cortisol So named because of their influence on gluconeogenesis (build glucose from other molecules) Helps body respond to physical stress Pain or tissue damage acts on hypothalamus to release ‘corticotropic releasing hormone’ CRH acts on anterior pituitary to release ‘adrenocorticotropic releasing hormone’ ACTH acts on mobilise energy Key concept: Steroids suppress inflammatory response Used extensively to treat inflammatory disorders ie. Asthma, COPD, Allergy, Rheumatoid Arthritis, IBS Hall J., H. M. (2021). Guyton and Hall Textbook of Medical Physiology (14th Ed). Philadelphia: Elsevier. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hypothalamic-pituitary-adrenal axis Cortical hormones are controlled by the HPA Significant role in the influence of stress on disease Area of intensive research in mental health disorders Can be disrupted by exogenous steroid therapies eg. Prednisolone Dexamethasone Hydrocortisone Feather A, R. D., Waterhouse M. (2021). Kumar and Clark's Clinical Medicine (10th Edition ed.). London: Elsevier. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Hypoadrenalism: Addison’s disease Destruction / failure of adrenal cortex Unable to mount normal physiological response to stress Caused by: Autoimmune disease Surgical removal Congenital hypoplasia Malignancy President John F Haemorrhage/infarction Kennedy 1917-1963 Post steroid therapy Long term therapy compromises HPA This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Addison’s Disease – Clinical Findings Often insidious onset Fatigue, Weakness Anorexia, abdominal pain & vomiting Weight loss Depression ↓ Na+ & ↑K+ Acute Adrenal Crisis Brought on by stress – infections, trauma, surgery Unable to respond – vomiting, abdominal pain and profound hypotension and eventually vascular collapse and death Treated with exogenous corticosteroids – hydrocortisone This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Acute adrenal crisis Addison’s is treated with long term steroid Treatment: therapy Any physiological stress needs to be - IV fluid matched with increased dose to prevent a crisis - Hydrocortisone Consider in any patient with Addison's or - ?IV Glucose, glucagon long-term steroid therapies - Electrolyte monitoring/correction Clinical Features: - Hypotension (shock) - Impaired consciousness - Fever - Vomiting - Abdo Pain - Hypoglycamia This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Cushing’s Syndrome Caused by adrenocortical excess due to Pituitary or adrenal tumours causing excess secretion As a significant consequence of steroid therapies Results in deranged metabolism and nutrient mobilisation, can lead to characteristic ‘cushingoid’ appearance changes Increased fat deposition (moon face, buffalo hump, abdominal obesity) Mobilisation of peripheral supportive tissue Muscle Weakness Osteoporosis Thin skin, striae and bruises This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Cushing’s Syndrome Also associated with significant physiological changes Hypertension Hyperglycaemia Psychological disturbances (psychosis, depression) Most frequently notable in a less severe form amongst patients treated with steroid therapies This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication https://casereports.bmj.com/content/2016/bcr-2016-215693 of this material by you may be the subject of copyright protection under the Act.  Cushing’s syndrome Understand the wide implications of adrenocortical excess on metabolism and physiology Appreciate the effects of exogenous steroid therapy in mimicking adrenal excess Link characteristic clinical features to patient risks Depressed inflammatory / immune response Hyperglycaemia HTN Mood disorders This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  Hyperaldosteronism (Conns Syndrome) Hypersecretion of aldosterone Tumour or 2nd to heart, kidney, liver failure Exaggerated effects: Na+ / H2O retention, K+ Loss Causes HTN, Hypo-K, Alkalosis, Arrhythmias, Tetany Management: Spiranolactone, ACE inhibitors, Ca+ channel antagonists, adrenalectomy Phaeochromocytoma Hypersecretion of catecholamines (from the medulla) Tumour Exaggerated stress response, often intermittent at first Hypertensive crisis, tachyarrhythmia, anxiety, diaphoresis, headache Management: Beta-blockers, alpha-blockers, anti-HTN, adrenalectomy This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Learning Check 4: Can you… 1. Name the hormones of the adrenal cortex and outline their key effects 2. Describe the control of adrenal hormone release and describe the consequences of hypo / hyper secretion 3. Outline the key implications of Hypoadrenalism to paramedic practice 4. Describe the implications of Hyperadrenalism & steroid therapy to paramedic practice, particularly the associated risks factors This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.  References and recommended reading Hall J, Hall M (2021). Guyton and Hall Textbook of Medical Physiology (14th Ed). Philadelphia: Elsevier. Kumar V, Abbas A, Aster M. (2021). Robbins & Cotran Pathologic Basis of Disease (10th Ed) Philadelphia: Elsevier. Feather A, Randall D, Waterhouse M (2021). Kumar and Clark's Clinical Medicine (10th Edition ed.). London: Elsevier. This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Thanks! This material has been reproduced and communicated to you by or on behalf of Flinders University in Accordance with section 113P of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act.