14 Flashcards
tear drop poikolytes
myelofibrosis
1st line for neutropenic sepsis
piperacillin with tazobactam
which SSRI do you use post MI
Sertraline-also give PPI for gastric protection as likely to be on aspirin and that with SSRI can cause bleeding
what is risk of SSRI in first trimester
small risk of congenital heart defects
risk of SSRI in third trimester
persistent pulmonary hypertension of newborn
which SSRI can be used in adolescents
fluoxetine
when is progesterone level measured
7 days before end of cycle
how does methyldopa work
centrally acting alpha agonist
how does labetalol work
B and a antagonist
how does nifedipine work
Ca channel antagonist
hydralazine
vasodilator
what class of drug is lidocaine and how does it work
Na channel antagonist so it causes inhibition
what are ionotropic and metabotrophic glutamate receptors important in discriminating between
ON and OFF retinal pathways
what do metabotrophic GABA tend to do
modulate synaptic actions because their slow action is insufficient to trigger an action potential
how do metabotrophic GABA modulate
presynaptically modulate transmitter release
transmitter gated channels to regulate size of post synaptic potential
resting and voltage gated ion channels in neuronal soma to alter eg resting Em and AP firing pattern
what does cholinergic transmission in autonomic ganglia display
both direct and indirect transmitter actions
what is fast EPSP cholinergic
due to activation of nicotinic (ionotrophic) Ach receptors, channels conduct na and k
what is slow EPSP cholinergic
activation of muscarinic (G protein coupled) Ach receptors, Ach closes K+ channel (M type)
what is a graded potential
a change in the rmp caused by an EPSP or IPSP but the magnitude of neurotransmitter release is not of a magnitude large enough to cross threshold and result in an AP
what does an interneurone do and release
locally acting, typically releases GABA and so brings about an IPSP and inhibition, function is local processing of information
what does a projection neuron do
neuron responsible for conveying signals to other parts of the brain, typically releases glutamate and so brings about an EPSP
what is the basis of vision
the dark current
what is the dark current
in dark the Vm is between the Ena and EK
in response to light PNa is decreases outer channels close), PK>Pna therefore hyperpolarises
what happens in light in terms of retinol
11-cis retinal is converted to all trans-retinal
what does trans-retinal do
molecular cascade that decreases cGMP, closure of cGMP-gated na channel, lowered na entry causes hyperpolarization
in terms of glutamate what happens in light
light less glutamate
what is receptive field
part of retina that needs to be stimulated to elicit APs from a ganglion cell
what is a horizontal cell
connects between photoreceptors and project to other photoreceptors and bipolar cells
describe the convergence with rods
high convergence (large spacing, lower density) this increases sensitivity and decreases acuity
describe features of rods
achromatic peripheral retina high convergence high light sensitivity low visual acuity
describe features of cones
chromatic central retina low convergence low light sensitivity high visual acuity
off pathway uses what type of glutamate receptor
ionotropic
on pathway uses what type of glutamate receptor
metabotropic
which cells produce action potentials
only ganglion and some amacrine cells produce action potentials (all other cells produce graded changes in membrane potential)
what is lateral inhibition and why is it helpful
it exaggerates the difference in stimulus intensity detected by adjacent neurons, aids with localization
lateral inhibition modifies the receptive fields of ganglion cells to have what type of organization
centre-surround
on centre-off surround
off center-on surround
does our visual system dtect differences in light intensity or amounts of light
light intensity
colour of short wave cone
blue
colour of middle wave cone
green
colour of long wave cone
red
what is the duplex theory of vision
rods and cones (rods=photopic) (cones=scotopic)
if CT is negative and you strongly suspect SAH how soon can you do lumbar puncture
no sooner than 12 hours after onset of symptoms
why do you need to wait 12 hours
to see if the spinal fluid is xanthrochromic (yellow) from the breakdown of blood in CSF
why do you give nimodipine in SAH
decrease in vasospasm to decrease cerebral ischaemia
what can carbamazepine be used to treat
trigeminal neuralgia, bipolar, temporal lobe epilepsy, complex partial seizures
what are features of anorexia nervosa
decrease in BMI, bradycardia, hypotension, enlarged salivary glands
hypokalaemia, low FSH, LH, oestrogen and testosterone
increased cortisol and growth hormone, impaired glucose tolerance
hypercholesterolaemia
dental carriers, dry skin, brittle hair, languo hair
what is first line for treatment of stroke and TIA
clopidogrel
name some screening tools for depressions
HAD and PHQ-9
antimuscarinics for urge incontinence
oxybutynin, tolterodine, darifenacin
what can precipitate an aplastic crisis in hereditary spherocytosis
parovirus
what is the other name for multisystem atrophy
shy dragger syndrome
what is contained in cryoprecipitate
plasma containing factor VIII, fibrinogen, vWF and Factor XIII
risk factor for bells palsy
pregnancy
what are the risk factors for cervical cancer
smoking
HIV
early age of first intercourse, many sexual partners, high parity, lower socioeconomic status, COCP, HPV 16 and 18
how does HPV 16 work
E6 which inhibits p54
how does HPV 18 work
E7 inhibits RB suppressor gene
what happens in cervical ripening
decrease in collagen fibre alignment, decrease in collagen fibre strength, decrease tensile strength of cervical matrix, increase in cervical decorin
what does anterior leg do
dorsiflex
what nerve is anterior leg supplied by
deep fibular
what are the ligaments of the hip joint
ishiofemoral, iliofemoral, pubofemoral
what is the blood supply to the hip
lateral and medial circumflex arteries from the deep femoral artery
artery to head of femur from obturator artery
which muscle externally rotates knee
biceps femoris
what type of injury is likely to cause a foot drop
fracture of neck of fibula
what does the latissimus dorsi do
adducts the shoulder joint, extends and medially rotaes shoulder
where is the confluence of the venous sinuses
at internal occipital protruberance which is in midline and deep to external occipital protruberance
what does the anterior longitudinal ligament do
prevents against over extension
what does posterior longitudinal ligament do
prevent against over flexion
what does the cauda equine consist of
all the L2-co spinal nerve roots descending towards their respective intervertebral foraminae (arranged with motor roots anteriorly, sensory roots posteriorly)
describe the path of the internal carotid
becomes internal to cranial cavity via carotid canal to supply the brain
describe vertberbal arteries path
pass through transverse foramina in cervical vertebrae then through foramen magnum to enter cranial cavity
how is haemophilia inherited
X linked recessive
what is the fibrinolytic system
causes fibrin dissolution and acts via generation of plasmin, Process starts with release of tissue plasminogen activator fro endothelial cells which is stimulated by fibrin formation
what is the combined test in pregnancy
hcg, PAPP-A, nuchal translucency
what is the triple/quadruple test
hcg, AFP, ( unconjugated estriol and inhibin-A) after 16 weeks
what blood results would you expect for downs mother
decrease in AFP, decrease in oestriol, decrease in PAPPA, increase in HCG and thickened nuchal translucency
when are triptans used `
for the treatment of migraine
what are the side effects of triptans
tingling, heat tightness in throat and chest
describe the symptoms of guillian barre
sensory symptoms proceed weakness pain is v common progressive paraplegia peak symptoms are 10-14 days into onset of symptoms association with campylobacter symmetrical symptoms autonomic dysfunction distal then ascending to proximal
where does botulism affect
presynaptic disorder
what classification describes some movement if gravity removed but none against gravity
2
what is rhobencephalon
hindbrain
what is a chorionic haematoma
common cause of bleeding in the first trimester
pooling of blood between endometrium and embryo due to separation
bleeding cramping, threatened miscarriage
symptoms and course follow size and perpetuation
usually self limiting and resolve
large haematoma may be source of infection, irritability and miscarriage
what nerve passes through the superficial inguinal ring
ilioinguinal
what is tumour lysis syndrome caused by
high potassium and phosphate and low calcium
how does body of uterus drain lymph and to where
lymphatics within braod ligament to iliac nodes
where is 4th ventricle
between cerebellum and pons
which type of SSRI do you avoid in breastfeeding an d hwy
fluoxetine because of its long half life
personality disorder associated with recurrent suicidal behaviour
borderline
what is postpartum haemorrhage defined as
> 500mls of blood loss
how do you treat B 12 deficiency due to pernicious anaemia
3 monthly IM hydroxocobalamin injections
where is B 12 absorbed from
ileum
how long do B12 stores last for
2-4 years
how long do folate stores last for
4 months
where is folate absorbed form
duodenum and jejunum
what is the MAC formed by
C5b and C6-C9
subcortical dopamine hyperactivity lead to
psychosis
mesocortical dopamine hypoactiivty leads to
negative cognitive symptoms
alteration in clotting factor levels induced by EE maybe thrombogenic are
decrease in antithrombin III and protein S
what is hysteroscopic sterelisation
insert implant into each fallopian tube with a hysteroscope, scar tissue forms around them and hence sterilised
side effects of SSRIs
GI upset, anxiety, agitation, insomnia, sexual dysfunction, hyponatraemia in elderly
describe why alcohol withdrawal is bad
leads to excess glutamate activity and decreased GABA
excess glutamate is toxic to the nerve cell
what are the major dopinergic pathways and what do they do
nigrostriatal-Extra pyramidal
tuberoinfundibular-prolactin release
mesolimbic/cortical-motivation and reward
