Elderly/Stroke/Dementia PPT Flashcards
why is creatinine level usually normal in elderly people even though the renal function is substantially reduced?
because they have reduced muscle mass so are producing less creatinine so there is less for the kidneys to eliminate.
What equation for creatinine clearance takes into account age and sex?
The Cockcroft and Gault equation.
What bedside observation is the most powerful predictor of stroke?
HTN
Name 6 things that can be done as primary prevention of ischaemic stroke
BP reduction, smoking cessation, reduced platelet aggregation, inhibition of blood clotting, cholesterol reduction, carotid endarterectomy or stenting
what is the primary prevention of haemorrhagic stroke?
BP reduction
If an acute ischaemic stroke has been diagnosed, what is the time frame in which you can thrombolyse with alteplase?
within 4.5hrs of onset of stroke symptosm
What is the time window in which you can do a thrombectomy for people with acute ischaemic stroke?
6hrs
what must you exclude before deciding to thrombolyse when you suspect an acute ischaemic stroke?
exclude intracranial haemorrhagaea by immediate head CT or MRI
Name 5 contraindications to thrombolysis
head trauma or prior stroke in past 3 months.
GI or genitourinary haemorrhage in pervious 21 days.
major surgery in previous 14 dayas
history of previous intracranial haemorrhage,
evidence of acute trauma or haemorrhage,
taking an oral anticoagulant (or INR >1.4),
heparin within 48hrs, seizure at onset of stroke,
systolic BP >185 or diastolic >110,
platelet count of <100/10^10,
Blood glucose <2.7
how much is the risk of an ischaemic stroke reduced by 2-5yrs after smoking cessation?
40%
how much does reducing cholesterol with a statin reduce the risk of a first stroke?
25%
What class of drugs is apixaban?
DOAC
what class of drug is dabigatran?
DOAC (factor Xa inhibitor)
What is the difference in mechanism of action of apixaban compared to dabigatran?
Apixaban prevents conversion of prothrombin to thrombin, whereas dabigatran directly inhibits thrombin preventing conversion of fibrinogen to fibrin.
Clots in the arterial circulation are largely driven by what?
platelets
clots in teh venous circulation are largely driven by what?
fibrin clot driven by the coagulation cascade
what is the mechonism of action of warfarin?
prevents liver production of vitamin K-dependent coagulation factors (factors II, VII, IX and X and proteins C and S).
It does this by inhibiting vitamin K epoxide reductase, the enzymre responsible for restoring vitamin K to its reduced form, necessary as a co-factor in teh syntehsis of these clottign factors.
after starting warfarin how long does it take to achieve full anticoagulation?
usually a few days
when starting someone on warfarin for anticoagulation but who needs immediate anticoagulation effects, what else should you start them on at teh same time?
heparin for immediate cover. stop once INR is in desired range.
what is the mechanism of action of clopidogrel, ticagrelor, prasugrel?
they prevent plateley aggregation by binding to adenosine diphosphate (ADP) receptors on teh surfeace of platelets.
What is the MOA of aspirin?
inhibits COX to reduce production of the pro-aggregatory factor thromboxane from arachidonic acid
what class of drug is dipyridamole?
anti-platelet
what is the MOA of statins?
HMG CoA reductase inhibitor - an enzyme involved in making cholesterol. they decrease cholesterol production by liver and increase clearance of LDLs. they slightly increase HDLs. through these effects they slow the atherosclerotic process.
name 3 acetylcholinesterase inhibitors used in Alzheimer’s disease
donepezil
galantamine
rivastigmine
what are the 3 most common side effects from acetylcholinesterase inhibitors?
N&V and diarrhoea
what is the mecahnism of memantine?
NMDA receptor antagonist. prevents glutamate-induced excitotoxicity but without interfering with actions of glutamate that are involved with memeor and learning.
What score does someone need to score on the MMSE to be classed as having moderate dementia, and thus able to start drug treatment?
10-20 points
what is the effect of cholinesterase inhibitors, such as rivastigmine, on mental function?
delays decline by 3-6 months
can you use a combination of cholinesterase inhibitor and memantine in Alzheimer’s?
yes - a combo can give additive benefits
after a pt with an ischaemic stroke has been treated with alteplase successfully, what further treatmetn should be prescibed int eh first few days following thrombolysis?
aspirin 300mg (should start it 24hrs after thrombolysis) for 2 wks before converting to long-term anti-thrombotic treatment
what is the best long-term antiplatelet that pts who have had an ischaemic stroke should be switched to
clopidogrel (75mg daily) as it is better tolerated long-term than aspirin
what is the MOA of clopidogrel
targets adenosine diphosphate (ADP) receptor and irreversibly inhibits it inhibiting ADP from binding to its platelet receptor. this overall inhibits platelet aggregation.
how long before surgery should you stop clopidogrel?
7 days
name 3 contra-indications for clopidogrel?
active bleeding, avoid in pregnancy, caution in hepatic/renal impairment
apart from antiplatelet therapy, what needs to be considered as secondary prevention for ischaemic stroke? (8 things)
ix for risk factors, lipid modification (statins), BP, physical activity, smoking cessation (if applicable), diet optimisation, reduce alcohol consupmtion, control of other co-morbidities e.g. diabetes
what routine ix should be performed on a pt who has had an ischaemic stroke with regards to specific risk factors for stroke?
carotid doppler - to check for carotid artery stenosis.
ECG - to check for AF.
ECHO - to check for structural cardiac disease
what is the CHADSVASC score for>
calculates stroke risk for pts with AF
what is the HASBLED score for?
checks the bleeding risk for pts on anticoagulants for AF
what do the letters in CHADSVASC stand for?
Congestive HF HTN Age 75yrs or older. DM Stroke/TIA hx Vascular disease Age 65-74 Sex Category (females at higher risk)
What does HASBLED stand for?
HTN, Abnormal renal or liver function, Stroke, Bleeding (hx or disposition). Labile INR Elderly (>65), Drugs or Alcohol (other antiplatelet agents or NSAIDs, >8units per week)
what should the systolic BP target be for a person who has had an ischaemic stroke in the past?
< 130mmHg
which groups of pts are at an increased risk of muscle toxicity from statins?
those with a personal or family hx of muscular disroders, high alcohol intake, hypothyroidism, renal impairment
how long must you not drive for after having a stroke?
one month then you can drive after this is there is satisfactory clinical recovery
