Week 2 - E. Coli, Kidneys, Fluids Flashcards
Outline daily fluid losses and fluid requirements in health What are the types and approximate values of fluid loss
Requirement / loss both about 2.5L Sensible - can sense and measure - urine, faeces, blood, sweating Insensible - can NOT sense / measure - breathing, evaporation from skin Sweating - 100ml Faeces - 100ml Urine - 1500ml Insensible (skins, lungs - not involving solutes) - 700ml Approximately 2.5L (2,500mL) a day Exercise, environmental factors increase output Normal water intake - 2-2.5 l per day TOTAL
Describe the main body fluid compartments, the major differences in their composition, the factors affecting water and solute transport between them
Intracellular - in cells about 2/3 Extracellular (Interstitial, plasma, transcellular) - about 1/3 Interstitial between cells Plasma in blood Transcellular is everything else (joints, CSF, etc) Solutes / fluid move between them through both active and passive transport (fluid can move due to osmotic pressure)
Hyper, hypo, isotonic
If ICF is more solute concentrated than ECF, conditions are hypotonic and fluid will try to move INTO the cell to balance which can result in lysis If ICF is less solute concentrated than ECP, conditions are hypertonic and fluid will try to move OUT of the cell which can result in shrivelling of the cell If equal, they are at equilibrium
Describe how and why the ECF and ICF alters in a) salt and water depletion b) net water depletion and c) net salt depletion
HYPOtonic dehyradtion - solute loss is greater than water loss - water will rush into cells to try to maintain ICF water content HYPERtonic - water loss is greater than solute loss - water will rush out of cells to try to maintain ECF water content ISOtonic - loss of both - water and solutes may move out of ICF into ECF
Describe the factors that influence membrane permeability to small and non-polar molecules (4 gradients, 1 other factor)
Concentration gradient, electrochemical gradient, pressure gradient, osmotic pressure gradient Properties of the membrane Membrane thickness/composition Aqueous pores in the membrane Transport mechanisms - Carrier-mediated transport Semi-permeable – allow H2O through
Outline what prevents transmembrane movement of polar molecules. Examples of can and can’t
Due to hydrophobic nature of tails inside membrane, uncharged, non-polar small molecules most easily through the membrane CAN: O2, CO2, H2O (smaller polar molecules CAN, larger CAN’T) CAN’T: Glucose, Ions (regardless of size)
Outline the types of passive transport (4)
Diffusion - Movement of solutes from high to low concentration, down concentration gradient, no energy required Osmosis - Movement of water from low to high solute concentration, down concentration gradient, no energy required Ion channels / Facilitated diffusion - does not require energy, through carrier protein, for ions /glucose etc. to move down concentration gradient - uniport
Outline the types of active transport (2 with examples)
Primary - directly uses ATP - PUMPs - Sodium / potassium pump Secondary - Uses existing favourable gradient symport, antiport, sodium glucose linked transporters, sodium calcium exchanger
Describe the rationale for oral rehydration therapy based on understanding of sodium, glucose and water transport mechanisms in the intestine
Isomotic dehydration means patient is losing both electrolytes and water Rehydration requires both of these to prevent differences between ICF / ECF Glucose required to maintain sodium/potassium pump so electrolytes and water continue start moving into cells equally
Describe gross structure of kidney - location, structure, blood supply
At the posterior alongside spinal column, renal artery/vein, surrounded by capsule, containing medulla and cortex regions, all filters into renal pelvis, which moves into ureter
Describe a nephron - structure, function
Afferent/efferent arteriole, Glomulerus, Bowman’s capsule, Proximal, convoluted tubule, loop of Henle, distal convoluted tubule, collecting duct
What is the kidney’s role in fluid balance? (4)
Filtration, reabsorption (out of nephron into blood), secretion (into nephron), excretion
Define what a drug is.
Drug - chemical that produces biological effects
Compare and contrast the anatomy and chemical transmission of the sympathetic and parasympathetic nervous systems.
Sympathetic - excite Thoracic / lumbar region Parasympathetic - calm Cervical / sacral region
Appreciate the different approaches to learning anatomy (5); understand ‘the anatomical position; appreciate the necessity to use correct anatomical terminology
Approaches: embryological, regional, cross sectional, systems, surface
Identify the embryonic origin in terms of endoderm, mesoderm and ectoderm of different body layers and the major viscera of the thoracic, abdominal and pelvic cavities
Endoderm - lining of gastro-intestinal system, respiratory and urogenital tract Mesoderm - Heart, blood vessels, muscle, kidneys, urogenital, connective tissue, skeleton Ectoderm - skin, brain, CNS, snesory organs, tooth enamel, hair, nails
Use appropriate anatomical terminology to describe the relationships between the major viscera and parts of the body
Discuss elements
Understand the principles of a systematic approach to clinical examination
Introduction and preparation - intro, consent, handwashing IPPA - including bedside observation Closure
Demonstrate awareness of the non-clinical determinants of health, including social, political, economic, environmental and gender disparities
Discuss elements
Recognise that health systems are structured and function differently across the globe using the WHO model of essential components of a health system (6 building blocks)
Building blocks are: leadership, finances, workforce, products/ technologies, information/ research, service delivery
Define the terms epidemiology and public health
Epidemiology - the study of the distribution and determinants of health and disease in human populations Public health - the science/art of prolonging life, preventing disease, promoting health in the population
Outline the aims and objectives of quantitative research in the clinical, biomedical and healthcare sciences (two types, 3 overall goals of both)
Experimental (intervention) and observational (no intervention) studies - to measure numerical data using specific design study health / illness find new treatments building knowledge
Describe briefly the design and purpose of experimental and observational clinical studies, including randomised controlled trials and cohort studies
Cohort - compares exposed with unexposed over time (investigator does not influence exposure) Randomised CT - compares exposed with unexposed (exposure is randomly determined by investigator in attempt to control for other factors)
Outline the rationale for, and approaches to, sampling in order to make inferences about a population
a sample is an ‘estimate population’ as its impossible to include everyone The larger and more representative of a particular population the better
Outline the principles, methods and use of reflective practice as a tool for clinicians to improve their resilience, quality of their work, and healthcare outcomes of the organisation they work within
Description, feelings, evaluation, analysis, conclusion, action plan
Outline how drugs work (three properties)
- tissue selectivity (drugs act in parts of the body, but not others) - chemical selectivity (changes in structure = altered action) - amplification of action (can work at low concentrations)
Define pharmacodynamics and pharmacokinetics
pharmacodynamics - what does the drug do to the body? MoA pharmacokinetics - What does the body do to the drug? How is it absorbed, distributed, metabolised, excreted?
Outline pharmacodynamics and pharmacokinetics of aspirin
pharmacodynamics - inhibits an enzyme called cyclooxygenase (COX) so it cannot catalyse the conversion of arachidonic acid into prostaglandins and thromboxanes (which dilate blood vessels, sensitive nerve endings, increase swelling, platelet aggregation) pharmacokinetics - A - oral, IV, IM, SC, inhalation - stomach and intestine, M - in liver, E - in urine
Outline pharmacodynamics and pharmacokinetics of opiates
pharmacodynamics - Activate opiod receptors (mu, kappa, delta) found in CNS and nerves terminals - effect is a reduction in neuronal cell excitability that in turn results in reduced transmission of nociceptive impulse (pain) pharmacokinetics - Varies depending on the opioid - Morphine can be taken IM, IV, SC, rectally, epidurally - metabolised by gut wall and liver, byproducts are excreted through urine
What are receptors? & 4 types
Binding site for specific drugs, enable intracellular activity Receptors, enzymes, carrier molecules, ion channels
What is an agonist?
A drug which binds to a receptor to produce biological cellular response
What is an antagonist?
A drug which binds to a receptor to prevent an agonist from having effect - does NOT produce biological response itself
What is affinity?
The process of a drug binding to a receptor, occupancy
What is efficacy?
The result of the bonding, the biological effect
Describe a partial agonist & provide an example
Less efficacy than a full agonist EXAMPLE: Buprenorphine for opioid addiction High affinity but less efficacy so you don’t have severe withdrawal, but prevents highs / overdose
Surmountable vs - non-surmountable antagonism
Surmountable - if you increase agonist concentration, it can overcome antagonist Non-surmountable - non-competitive (binds to a different site but prevents activity) or irreversible (binds to site reducing space for agonist)
What does ADME stand for? Significance?
Absorption, distribution, metabolism, excretion Significant element of pharmacokinetics
How do you calculate ‘rate’?
Number of cases / popultation at risk
Define incidence, prevalence
Incidence - new cases of disease Prevalence - presence of disease (new and old)
Describe anterior, distal, ventral, inferior, posterior, superficial, superior, dorsal, plantar, palmar, intermediate, medial, proximal, transverse, coronal, dorsal, deep
xxx
Describe flexion, extension, circumduction, eversion, elevation, opposition, reposition, inverson, depression, abduction, adduction, lateral vs medial rotation, supination, pronation- of different parts of the body
flexion generally bringing two ventral / anterior surfaces together
Regional - axial
head, neck and trunk
regional - appendicular
appendages, limbs
FRONT frontal buccal coxal inguinal pollex crural hallux antecubital acromial cervical tarsal
Anterior forehead cheek hip groin thumb leg big toe front of elbow point of shoulder neck ankle
BACK otic cephalic olecranal sacral perineal popliteal sural calcaneal
Posterior ear head back of elbow between hips between anus and genitalia back of knee calf heel
Different types of scans
X-ray - As x-rays pass through the body, energy particles (called photons) are absorbed at different rates MRI - using magnets and radio waves to show detailed cross sectional images (better in pregnancy, allergy to contrast) Ultrasound- high-frequency sound waves to create an image of part of the inside of the body. CT - narrow x-rays to show slices PET/CT - radiotracer or ‘tracer’ (radioactive form of sugar) to show up the most active cells in your body.
Post-ganglionic parasympathetic nerves generally release BLANK which acts at BLANK receptors The exception is…?
Blank one - Acetyl choline Blank two - muscarinic NANC nerves which use other chemical such as nitric oxide
Post-ganglionic sympathetic nerves generally release BLANK which acts at BLANK receptors The exception is…?
Blank one - Noradrenaline Blank two - alpha/beta adrenoreceptors Sweat glands, sympathetic nerves release Ach at Muscarinic receptors
