General Flashcards
What are the question topics for taking a history of a presenting complaint?
S - Subject O - Onset C - Characteristics R - Radiating A - Associated Factors T - Timing E - Exacerbating Factors S - Scale I - Impact A - 'Anything else?'
- Red flags?
What are the question topics for taking a comprehensive history?
- Current General Health
- Medical History
- Medications
- Allergies
- Family History
- Social History
- Lifestyle - Use of Illicit Drugs
- Lifestyle - Alcohol
- Lifestyle - Smoking
- Lifestyle Exercise/Physical Activity
- Diet
- Red Flags
- Is there anything else?
What is the Calgary-Cambridge framework?
- Initiating Interview
- Gathering Info
- Physical Exam, then any other tests
- Explaining and Planning
- Close Session
What is the composition of fluid compartments in the body?
- Extracellular Fluid (35%) (in-between cell and capillary)
i. Interstitial Fluid (25%)
ii. Blood plasma and lymph (8%)
iii. Trans-cellular fluid (2%) (water in epithelial lined spaces) - Intracellular Fluid (65%)
What are the types of cellular communication?
- Direct:
i. Juxtacrine
ii. Gap Junctions - Via ECF:
i. Autocrine
ii. Paracrine
iii. Endocrine
iv. Neuronal
v. Neuroendocrine
What are the main constituents in the extracellular fluid and intracellular fluid?
3 Main constituents in ECF:
- Na+
- Cl-
HCO3-
3 Main constituents in ICF:
- K+
- PO43-
- Protein Anions
Describe feedforward control
An anticipatory alteration of effectors independent of feedback. There is adaptive control (I,e, system learns how to control ball throwing) and anticipatory control (or predictive homeostasis, i.e. increasing cardiac function in anticipation of exertion
Describe the Baroreceptor Reflex
- A decrease in BP result in BR in heart being stretched less. (decrease nerve impulses)
- Info sent to brain (afferent info)
- Brain increases sympathetic simulation and decreases parasympathetic (efferent info)
- Increased secretion of adrenaline and noradrenaline
- Increased heart stroke volume and heart rate (=increased cardiac output), and constriction of blood vessels (=increase in SVR).
- BP rises and homeostasis is maintaines
Describe plasma glucose in terms of homeostasis
If it is too high, pancreas will release insulin into blood and cells can use glucose as energy or convert it into glycogen, and liver will convert glucose to glycogen as well. Blood glucose levels drop and homeostasis in maintained.
If it is too low, pancreas will release glucagon into blood and so liver will convert glycogen into glucose, which raises blood glucose levels and homeostasis is maintained.
Describe the positive feedback cycle involving oxytocin in childbirth
- Head of fetus pushes against cervix
- Nerve impulses from cervix transmitted to brain
- Brain stimulates pituitary gland to secrete oxytocin
- Oxytocin carried in blood stream to uterus
- Oxytocin stimulates uterine contractions and pushes fetus toward cervix, when restarts the cycle
What are the determinants of ion diffusion across a membrane?
- membrane permeability
- concentration gradient
- voltage gradient
What causes cystic fibrosis?
A defective gated Cl- membrane transport protein (cystic fibrosis trans membrane conductance regulator (CFTR)) results in cells not being able to get rid of Cl- fast enough, so too much water is let in. The cells can’t regulate Cl- secretion and so mucus becomes excessively thick.
What are the main types of endocytosis?
- Fluid phase
- Receptor mediated
- phagocytosis
What are the main types of exocytosis?
- Constitutive (unregulated)
- Regulated
What is the rate of passive diffusion of an uncharged substance?
ΔS/Δt = -D(ΔC/Δx)
(rate of passive diffusion = proportionality constant x concentration gradient at a point).
P (permeability coefficient) = DΔx.
therefore:
Net flow of solute = -PΔC
What factors affect the permeability coefficient?
- size and shape of molecule
- lipid solubility
- electrical charge
- ability to form H-bonds (hydrophilic)
- chemical structure of molecule and cell membrane
What is the typical osmolarity of ICF and ECF in mammals?
300mOsmoles/L
What factors that need to be taken into account when determining the effective osmotic pressure difference?
- The total concentration of dissolved solutes
- Degree of dissociation of each dissolved solute
- Permeability of the membrane to each substance
What is the approximate hydrostatic pressure equivalent of 1 Osmole/L?
22.4 atmospheres = 22.4 x 760 mm Hg
What causes the different between tonicity and osmolarity?
ECF and ICF can have same osmolarity, but they may have different concentrations of different solutes. Permeability of these solutes effects tonicity, which is a measure of EFFECTIVE osmotic pressure.
What is Tonicity?
A measure of EFFECTIVE osmotic pressure.
What are the defining features of cardiac muscle?
Single nucleus, striated and involuntary.
What are the defining features of smooth muscle?
Single nucleus, NOT striated and involuntary.
What are the defining features of skeletal muscle?
Multiple nuclei, striated, voluntary
What are the different connective tissues in/around a muscle cell?
Epimysium (ensheaths entire muscle)
Perimysium (surrounds bundle of muscle fibers)
Endomysium (unsheathes cells)
What are the main sections of a sarcomere?
Whole Sarcomere = Z - Z
I Band = Z + actin and titin on either side
A Band = Myosin
H Zone = Gap between actin (i.e. just myosin)
M line = middle of H zone
Which sections of the sarcomere shorten during contraction?
I and H
What is Excitation–contraction coupling?
Excitation–contraction coupling is the process by which a muscular action potential in the muscle fiber causes the myofibrils to contract.
What is Motor unit recruitment?
Motor unit recruitment is a measure of how many motor neurons are activated in a particular muscle, and therefore is a measure of how many muscle fibers of that muscle are activated. The higher the recruitment the stronger the muscle contraction will be.
What are the 2 main skeletal muscle finer types?
- Type I – SO – Slow contracting, fatigue resistant, low strength
- Type IIa – FO – Fast contracting, fatigue resistant, high strength
- Type IIb – FG – Fast contracting, fast fatigue, highest strength, and also the largest.
What are the phases of a twitch?
- latent period
- contraction phase (ends at peak)
- relaxation phase (peak to end)
What is the difference between isometric and isotonic tension?
Isometric tension occurs when tension in muscle is equal to the opposing force. The muscle stays the same length.
Isotonic tension occurs when they are not qual, and results in either shortening or elongation of the muscle.
What is unfused tetanus, fused tetanus and maximal tetanic tension?
Unfused Tetanus: if stimuli continue to be applied frequently to a muscle over a prolonged period of time, the maximum possible muscle force from each stimulus will eventually reach a plateau state known as unfused tetanus
Fused Tetanus: If stimuli are then applied with even greater frequency, the twitches will begin to fuse so that the peaks and valleys of each twitch become indistinguishable, known as fused tetanus.
Maximal Tetanic Tension: When the stimulus frequency reaches a value beyond which no further increases in force are generated by the muscle, the muscle has reached its maximal tetanic tension.
What is treppe and what is wave summation?
Treppe is the progressive increase in force generated when a muscle is stimulated in succession, such that muscle twitches follow one another closely, with each successive twitch peaking slightly higher than the one before. Step like. Muscles relax between stimuli.
Wave summation - When a skeletal muscle is stimulated repeatedly, such that the stimuli arrive one after another within a short period of time, muscle twitches can overlap with each other and result in a stronger muscle contraction than a stand-alone twitch. Muscles don’t relax between stimuli.
What is threshold voltage?
The smallest stimulus required to induce an action potential in a muscle fibre’s plasma membrane
What is maximal tension?
ALL the muscle fibers have been activated by a sufficiently strong stimulus.
What are Glycosidic bonds and in what macromolecule are they relevant?
Glycosidic bonds are covalent bonds forms between monosaccharides from a condensation reaction. I.e. glucose. An O atom bonds to carbons on each monosaccharide.
What causes lactose intolerance?
Lack of lactase – the enzyme that breaks down lactose into glucose and galactose. Bacteria multiply in the undigested milk sugar in the gut which results in gas, cramps, bloating.
Can be seen in children after one month if they pull legs up in pain after 1-2 hours after feeding screaming.
Primary Lactose Intolerance – remove lactose from diet
Secondary lactose intolerance – following bad GI infection, can last months.
What is Rickets?
Disorder involving lipids (cholesterol and Vitamin D (cholecalciferol). At age one year, will be underweight with soft, pliable bonds (inadequate calcification). Receive vitamin D treatment.
In adults – osteomalacia.
What is Phenylketonuria?
At 9 days – mild jaundice
Untreated at age 4 – mental retardation by 2, seizures, irrational behavior, eczema, mousy odour, pallid.
Due to impaired conversion of phenylalanine to tyrosine, usually because of defective phenylalanine hydroxylase so get Phe accumulation.
Controlled by decreasing dietry intake of Phe
What are the 3 cell junctions between epithelial cells?
- Adhering junctions – strong bonds that keep sheets intact and adhere cells together.
- Occluding Junctions – seal off intercellular space.
- Gap junctions - communication between cells
Desmosome are junctional complex discrete units that adhere cells
What are the two constituents of intercellular matrix?
a) Fibers
b) Ground substance
What are the different types of Fibers?
I. Collagen (white).
- thicker bundles, generally wavy
- resists stretching when straight
- many biochemical types
- tendons are predominantly collagen, and their resistance makes them able to transfer force.
II. Elastic (yellowish)
- Fibers or sheets (laminae)
- if fibers, then thin, straight, branches.
III. Reticular Fibers (type of collagen)
- invisible with H&E
- very thin, network
- support in highly cellular tissue s
Connective Tissue has two classifications…
What are their main purposes?
- Loose (either fibbers or ground)
- allow stretching and movement
- medium for nerves and blood vessels
- Passage of nutrients, waste, oxygen etc (ground)
- contains defines related cells - Dense:
- deep fascia (ct sheet envelops for muscles)
- tendons
- ligaments
- dermis (part of skin)
What are the types of PNS nerves?
- Cranial (12 pairs)
- Spinal (31 pairs)
What are the two types of components the cortex has?
Cerebral cortex:
- Sulci (grooves)
- Gyri (folds)
Cerebellar cortex:
- folio (parallel fine folds)
What is the brainstem and hindbrain made up of?
Brainstem:
Midbrain, pons, medulla oblongata
Hindbrain:
Pons and medulla oblongata
What are the spinal chord nerve pairs?
- 8 cervical (neck)
- 12 thoracic
- 5 lumbar (abdominal)
- 5 sacral (pelvis)
- 1 coccygeal (coccyx)
TOTAL = 31 pairs
What are the neurotransmitters for pre and post ganglionic fibers in the ANS?
Pre - use acetylcholine (cholinergic)
Post + Sympathetic - noradrenalin (adrenergic)
Post + Para - acetylcholine (cholinergic)
Define potency, effectiveness, affinity and efficacy.
Potency is the dose required to produce an effect.
Effectiveness is the level of effect a given dose will give.
Affinity - tendency of a drug to bind to a receptor.
Efficacy - ability of a drug to activate a receptor (antagonist is zero).
What does the dose-response relationship describe?
Differences in drug potency and effectiveness.
What are the 4 main processes of pharmacokinetics?
- absorption
- distribution
- metabolism
- excretion
What factors affect absorption of drugs?
- size (MW)
- solubility
- polarity/charge
- transporters
What is the bioavailability of a drug?
A simple way of describing how well a drug is absorbed from the site of admin (usually GI tract). Reported as F (fraction) and assesses extent of drug absorption – NOT RATE.
What does a high Vdist mean for a drug?
There is a low concentration of the drug in plasma compared to the dosage given. This means that the drug has been more widely distributed.
What are the major drug biotranformation reactions?
a) oxidation
b) sulfation
c) glucuronidation
How are drugs eliminated/excreted from body?
- body fluid and secretions
- expired air
- tissue shedding
what key processes contain renal drug excretion?
- filtration – free (unbound) drugs filtered through pores in glomerulus.
- Active transport – energy dependent transporters extract it from blood
- Diffusion (back into blood) (reabsorption)
What are the two cholinergic receptors of the parasympathetic nervous system?
- muscarinic cholinoceptor (M)
- nicotinic cholinoceptor (N) (ganglion)
What does the M2 receptor effect?
Heart - decreases heart rate
What does the M3 receptor effect?
Smooth muscle and glands - contract and secrete
What does the a1 receptor effect?
vascular smooth muscle - contract
What does the b1 receptor effect?
Heart - increase heart rate and force
What does the b2 receptor effect?
Smooth muscle - relaxes
What are the main adrenoceptor agonists and which receptors do they block?
a) phenylephrine - a1
Primary effect = vasoconstriction
b) Salbutamol - b2
Primary effect - causes relation of smooth muscle (i.e. ventolin)
What are the main adrenoceptor ANTagonists and which receptors do they block?
a) Prazosin – a1
Primary effect - vasodilation
b) Propranolol – b1 and b2
Primary effect - increase heart rate, BUT may may exacerbate bronchoconstriction in asthma
c) Metoprolol - b1 and b2
- same as above but less b2 at normal doses
What is mental first aid?
- Approach, Assess and Assist
- Listen non-judgmentally
- Give support and info
- encourage them to get appropriate help
- encourage other supports (i.e. family and friends)
A, L, S, E, E
What are the bradford hill criteria?
STAB PECCS
Strength
Temporality
Analogy
Biological Gradient
Plausibility Experiment Consistency Coherence Specificity
What is a DALY?
Disability adjusted life year. It allows the effects of different diseases and injuries to be compared on an equal basis. One ‘DALY’ is one year of healthy life lost due to premature death, prolongs illness or disability or a combo.
Leading causes of disease in Aus?
ACADCDC SLH
Asthma Anxiety/Depression Colorectal Cancer COPD CHD Diabetes Type 2 Dementia Stroke Lung Cancer Adult onset Hearing Loss
What is health?
A state of complete physical, mental and social wellbeing, and not just the absence of disease.
Ethics?
- Autonomy
- non-maleficence
- beneficence
- justice
Deontology?
Search for well-founded rules that serve as the basis for making moral decisions. Often no room for disagreement about what they require (i.e. killing is sin).
Utilitarianism?
Analysis of likely consequences or outcomes of options.
Principle based ethics?
Takes into account both rules and consequences.
Virtue Ethics?
CCJTIVFFSP
- Capacity of Self Reflection
- Compassion
- Justice
- Temperance
- Integrity
- Veracity (truthfulness)
- Fidelity to trust
- Fortitude (courage)
- Self-effacement
- Phronesis (practical wisdom)
Valid consent?
SCUFD
Specific for the proposed procedure Competent to consent Understands Freely given Disclosure
Exceptions to confidentiality?
RLDOR
- Risk to patient/third party
- Exception at law
- Doctors in medical Team
- Overwhelming social interest
- Approved Research
What is culture?
A dynamic concept which identifies systems of rules, beliefs, attitudes, values and behaviours shared by a group, taught across generations, relatively stable but capable of change across time
BRAVB
Millennium Developments Goals?
PhEG CMAEP
- Eradicate Extreme Poverty and Hunger
- Achieve universal primary Education
- Promote Gener equality and empower women
- Decrease Child Mortality
- Improve Maternal health
- Combat HIV/AIDS, malaria and other diseases
- Ensure Environmental Sustainability
- A global Partnership for development
4 Sustainability Development Goals?
WWLLE
- clean water and sanitation
- life on land
- life below the water
- affordable and clean energy
- decent work and eco growth
