Psych Flashcards
what is delirium
acute confusional state - reversible
with fluctuating symptoms
disturbed awareness/attention + cognition
usually elderly pts
what are the 3 types of delirium
hyper + hypo-active, mixed delirium
hyper: inappropriate behaviour, agitation
hypo: quiet, lethargic, reduced conc, reduced activity
what causes delirium
P - pain
I - infection
N - nutrition
C - constipation
H - dehydrated
M - medication
E - electrolyte disturbance (hypoNa, hyperK, hypo OR hyper Ca)
also sleep deprivation
how is delirium managed
treat underlying cause
always de-escalate first
if extremely agitated,
IV lorazepam
PO/IM haloperidol/olanzapine - avoid if PD/DLB as worsens movement disorder
what are RF for delirium
old age, multiple co-morbidities
frail
malnutrition
excess alcohol
how is delirium investigated
diagnosed by DSM5 criteria
assess cognition:
CAM, 4A test, AMTS
investigate to exclude organic cause:
B12, folate, Ca, VitD, TFT, glucose - main tests
TFT - hypothyroidism
UE - hypoNa, hyperK, hypo/hyperCa
what is depression
diagnosed by DSM5
at least 2 weeks of:
persistent low mood, anergia, anhedonia
additional symptom:
sleep disturbance (early morning waking), weight/appetite changed, reduced conc
feeling guilty/worthless, low libido
nihilistic delusions
what is severity of depression
mild (treat with CBT only) - minor/no functional impairment
moderate (CBT + consider medication) - symptomatic and more impairment
major (CBT + SSRI) - marked functional impairment, can cause psychosis (affect congruent delusions)
what are RF for depression
peak 25-35yr
diathesis/vulnerability:
female, genes (FH of depression)
stress:
PMH - chronic illness, previous depression
SH - unemployed, homeless, trauma, abuse
how is depression investigated
TFT - exclude hypothyroidism
FBC, bone profile, HbA1c, serum cortisol, B12/B9
brain imaging
what is pathophysiology of depression
monoamine hypothesis
(5HT projected from raphe nulceus)
lack of tryptophan
(precursor for 5HT - lack in diet)
depleted 5HT in synapse causes depression
(SE of reserpine anti-HTN, causes rapid depletion of 5HT so less uptake by 5HT2 receptors post-synaptically and less 5HT recycled by SERT receptors pre-synaptically)
what are monoamines
5HT, DA, NA, adrenaline, histamine
derived from aromatic acids
act on adenyl cyclase or phospholipase C
degraded by monoamine oxidase (MAO)
how do SSRI work
block SERT receptors on pre-synaptic membrane
so less 5HT recycled
increases 5HT action post-synaptically on 5HT2 receptor
so more downstream activation of adenyl cyclase
improving mood, so less depressed
where does NA come from + project to
from LC locus coreulus
projects to limbic system and frontal lobe
what is the difference between fear + anxiety
fear = imminent danger
anxiety = anticipating potential threat
what part of brain is involved in anxiety
amygdala
differentiates sensory info from thalamus to identify threat from no threat
if threat perceived, amygdala initiates physiological response (activates basal forebrain, so cortisol release through HPA axis)
what is pathophysiology of anxiety
HPA axis overstimulated
chronic stress exposure + prolonged raised cortisol occurs
what are key symptoms of PTSD + pathophysiology
hyper vigilance, flashback, nightmares, avoidance
due to:
shrunken hippocampus, so can’t function well - less memory processing/storage
limbic system dysfunction
thalamus receives sensory input of trigger (smell)
hippocampus recalls memory
amygdala reacts to memory
PFC can’t rationalise current situation
so pt escapes/avoids situation
what are types of anxiety
continuous (hyperthyroid, hypoPTH):
GAD - everything is a trigger, anxiety most days
PTSD - v.stressful event
episodic (substance abuse, pheochromocytoma):
panic disorder - recurrent unpredictable panic attacks
phobia - specific fear
OCD - obsessive intrusive thoughts, compulsive repetitive acts
