Analyse & respond to client health info - Lec 2.pptx

HLTAAP003- Analyse and Respond to client health information Session 2- Homeostatic imbalance and disease process HLT54121 Diploma of Nursing CRICOS provider number: 00122A | RTO Code: 3046 Session 2 Objectives By the end of thi...

HLTAAP003- Analyse and Respond to client health information Session 2- Homeostatic imbalance and disease process HLT54121 Diploma of Nursing CRICOS provider number: 00122A | RTO Code: 3046 Session 2 Objectives By the end of this session, learners will be able to: Define Homeostasis and feedback mechanisms. Explain body fluid compartments and fluid-electrolyte balance. Identify transport systems (active and passive). Identify acid, bases and their regulation. Identify the major acid-base imbalances. What is Homeostasis? Homeostasis – maintenance of a stable internal environment Necessary for normal body functioning and to sustain life Response to a changing external environment Homeostatic imbalance at least partly results in a disease What are some physiological variables? Temperature Water and electrolyte concentrations pH of body fluids Blood and tissue oxygen and carbon dioxide levels Blood pressure Blood glucose Levels How is homeostasis maintained? Providing a means for response to the stimulus by communicating through neural and hormonal control systems Information flows from control centre to effector down the efferent pathway (Watson, 2018) Can you identify? Body systems involved in maintaining homeostasis What are the elements of a homeostatic control system? 3 Input: Information is sent along Control afferent Center 4 Output: Information pathway to control is sent along center. efferent Efferent pathway effector. 2 Receptor pathw Afferent pathway detects change Receptor ay Effector 5 Response of effector feeds back to reduce 1 the effect of Stimulus stimulus and produces returns change in variable to VARIABLE (in homeostasis) homeostatic variable. level. Lets see how do these work together for thermoregulation? Image source: https://homeostasiseleishabiology.weebly.com/th ermoregulation.html What are the feedback mechanisms in this process? 2 types of mechanisms: -ve and +ve Negative feedback mechanisms  Reduce the original stimulus  Essential  All –ve feedback mechanisms have the same goal to prevent sudden changes within the body (Watson, 2018) Feedback Mechanisms continued… Positive Feedback mechanism  Intensify the initial stimulus  Leads to an enhancement  Rarely contribute to homeostasis  Likely to race out of control  Not appropriate for moment to moment (Watson, 2018) Lets have a look at this negative feedback mechanism You have skipped lunch and it is now about 1400hrs. Because your BGL is low, receptors in the pancreas are stimulated and glucagon is secreted. To maintain homeostasis, What will glucagon do? Consequently, what will happen to the BGL? This Photo by Unknown Author is licensed under CC BY-SA-NC Lets have a look at this positive feedback mechanism Blood clotting is a normal response to a break in the lining of a blood vessel Platelets immediately begin to cling to the injured site, chemicals are released to attract more platelets, and finally a clot is formed. Also known as the “clotting cascade” But what if it becomes out of control? https://www.youtube.com/watc h?v=Iz0Q9nTZCw4 https://www.youtube.com/watch?v=Iz0Q9nTZCw4 (watch till 5:15 mins) What are the Body’s fluid compartments? https://www.youtube.com/watch?v=v3BTWpNTyLU (watch till 02:00 mins) What is Fluids balance? Fluid balance is the correct balance of fluid input and output which is crucial to the health of the individual. Fluid gain in the body is a homeostatic mechanism which is triggered by dehydration Fluid loss from the body is mainly regulated by the kidneys and determined by the levels of sodium chloride excreted in the urine through hormonal control What are Electrolytes? Electrolytes – ions found in body fluids. They are needed by cells to regulate the flow of water molecules across the cell membranes Major ions and their functions: Sodium (Na+) regulates ECF volume, osmotic pressure, fluid balance Potassium (K+) responsible for nerve muscle function, neuromuscular excitability, ICF Calcium (Ca+) assists in muscle contraction/ blood clotting & strengthens bones and teeth, ECF Electrolytes continued… Magnesium (Mg²+) assists in nerve muscle function, ICF Chloride (Cl) assists with ECF volume control, fluid balance and osmotic pressure Bicarbonate (HCO₃) assists in acid-base balance, ECF space Phosphate (PO₄³) assists in acid-base balance/energy/strengthens bones Why do nutrients, wastes and water move? Nutrients that surround cells (such as glucose, oxygen, & amino acids) are needed inside the cell and must be able to cross the cell membrane. The waste which accumulates within the cell must also be able to cross the cell membrane to be eliminated from the body. What are the transport systems to move these? Transport mechanisms assist in the movement of dissolved substances and water across the cell membrane An introduction to active vs passive transport. https://www.youtube.com/watch?v=3k7Y6NcXe6s (1:59 mins) Transport systems continued… Active Transport Moves a substance from an area of low concentration to an area of high concentration (against the concentration gradient) with an input of energy (ATP) Adenosine triphosphate (ATP) Produced in mitochondria of the cell Majorly during Cellular respiration in which cells break down glucose into simpler products like CO 2 and water H 2 O As the molecule breaks down, the energy is released and some is converted into heat while some is transferred to high energy bonds of ATP (Koutoukidis, 2021) Where does it occur in body? Re-absorption of glucose, amino acids and salts by the kidney. Re-absorption of nutrients by the intestines. Sodium/potassium pump in cell membranes (especially nerve cells) What is Passive transport? Moves a substance passively without any input of energy from an area of high concentration to an area of low concentration (down the concentration gradient) Types of Passive transport Diffusion (Simple vs facilitated) Osmosis Filtration (Koutoukidis, 2021) What is Simple diffusion?  Moves a molecule from high solute concentration to low solute concentration  No energy or facilitated proteins are required  Molecules tend to distribute themselves evenly within the solution/fluid  Net movement of molecules stops when the concentrations are equal in both areas  Some major examples of diffusion include: Gas exchange at the alveoli  Gas exchange for cellular respiration What is Facilitated diffusion?  Moves lipid-insoluble and large substances that cannot simply diffuse from high solute concentration to low solute concentration  Protein membrane channels or protein carrier molecules facilitate this process for e.g. in Glucose transport into the cells  No energy is required This Photo by Unknown Author is licensed under CC BY-SA-NC  What is Osmosis? Moves water (solvent) ’down’ a concentration gradient Moves water from a region of low solute concentration to one of high solute concentration across a semipermeable membrane Involves an opposing force that prevents a solvent from moving across the membrane (Osmotic pressure) Brown, 2020 Diffusion and Osmosis in a nutshell https://www.youtube.com/watch?v=PRi6uHDKeW4 (3:51 mins) Filtration  Water and dissolved solutes move through a membrane (i.e. capillary wall) by fluid or hydrostatic pressure  Hydrostatic pressure is the force exerted by blood against the walls of the blood vessels to move fluid from capillaries into extracellular fluid  The fluid moves from a from a high-pressure area to a lower-pressure area Which body organ reminds you of this process? Brown, 2020 In-class canvas activity- Pamela Scott Case study Refer to canvas module – Week 1: Session 2:Pamela Scott- Case study worksheet (Electrolytes imbalance) What are acids and bases? Acids Chemicals that release hydrogen ions (H+) when dissolved in water Proton donors Can you think of an acid in your stomach? Bases Chemicals that release hydroxyl ions (OH–) when dissolved in water Proton acceptors Bicarbonate ion (HCO3-) is an important base in the body What is pH? It measures the relative hydrogen ions concentration in a solution Scale of 0-14 pH below 7 = acidic pH 7 = neutral pH above 7 = basic (alkaline)  What pH do different bodily fluids have? Are these acidic or alkaline? This Photo by Unknown Author is licensed under CC BY-NC-ND Saliva= Between 5.4-7.5 Stomach= Highly acidic- very low pH Image source: https://jooinn.com/blood- cells.html Blood= Between 7.35-7.45 (Brown, 2020) Why acid-base balance is needed? Chemical reactions in the body occur at a particular pH level Any alteration in pH interferes with these reactions Changes in pH profoundly affect cardiac and neurologic function This Photo by Unknown Author is licensed under CC BY-SA This Photo by Unknown Author is licensed under CC BY What helps in the regulation of acid-base balance? This is regulated by 3 mechanisms: Respiratory mechanisms Renal mechanisms Blood buffers (H+ ions bind or release) https://www.youtube.com/watch?v=VzEEs00v-JU&t=113s (Watch from 1:31-2:28 mins) Acid-base regulation by blood buffers https://www.youtube.com/watch?v=X3VdcLD6h9w (0:57 secs) What are the major acid-base imbalances? Acid base imbalances will develop when the body is unable to regulate pH: Acidosis – pH less than 7.35 (respiratory and metabolic) Alkalosis – pH higher than 7.45 (respiratory and metabolic) (Brown, 2020) Acid – Base imbalances continued… Acidosis: Accumulation of too much acid in the body causing the blood pH to fall below 7.35 S/S: headache, anxiety, blurred vision, restlessness, confusion and eventually coma if not treated Respiratory acidosis: Any condition that causes hypoventilation (emphysema, asthma) resulting in high CO2 levels (CO2 is acidic in nature) Metabolic acidosis : Conditions in which kidneys retain H+ and excrete HCO3 (kidney disease, DKA, severe vomiting and diarrhoea) (Brown, 2020) Acid – Base imbalances continued… Alkalosis: accumulation of too much base in the body causing the blood pH to go above 7.45 S/S: dizziness, numbness or muscle spasms in the hands and feet, angina or chest discomfort, confusion, dry mouth, heart palpitations, confusion, coma if not treated Respiratory alkalosis: Any condition that causes Hyperventilation resulting in low CO2 in blood e.g. panic attacks, extreme anxiety and pain Metabolic alkalosis: Persistent vomiting resulting in loss of H+ ions, over ingestion of antacids resulting in increase of HCO3 ions (Brown, 2020) To summarize… How respiratory acidosis and alkalosis are compensated? https://www.youtube.com/watch?v=KmkjS_XnCw4 (0:59 secs) How metabolic acidosis and alkalosis are compensated? https://www.youtube.com/watch?v=NWlmUYK2url (0:42 secs) What is Arterial Blood Gas Analysis (ABG’s) Analysis shows how well a person’s lungs are delivering oxygen to the blood stream and eliminating carbon dioxide Post session activity from home Refer to canvas module –Week 1: Session 1 and 2 to complete the ‘Practice quiz post session 1 and 2’ Any questions?  RMIT Classification: Trusted In-class timed assessment: AT1- Knowledge Quiz and Case study Assessment 1 due date as per canvas in Week 3) This Photo by Unknown Author is licensed under CC BY-NC References Brown, D. (2020). Lewis’s Medical-Surgical Nursing: ANZ, (5th ed.). Elsevier. Australia. Koutoukidis, G. (2021). Tabbner’s nursing care; theory and practice, (8th ed.) Elsevier. Australia. Watson, R. (2018 ). Anatomy and Physiology for Nurses, (14th ed.). Elsevier. Australia