Geriatrics Flashcards
Pharmacokinetic changes in the elderly
ADME?
Absorption
- _______ which reduces oral bio-availability
- ______ (even if not taking PPI), which decreases breakdown of enteric coatings (decreases absorption); increases absorption of some drugs (eg methyldopa)
- ______ in the gut for calcium, folate, vitamin B12
Distribution
- Reduced skeletal muscle mass with increased ratio body fat to water
- Volume of distribution for water soluble drugs decreases, increasing serum concentration (e.g. paracetamol, digoxin)
- Volume distribution for fat soluble drugs increases, leading to prolonged half-life and more toxicity (e.g. diazepam, amiodarone, verapamil)
- Decreased albumin levels
- Increased free fraction of highly albumin-bound drugs (e.g. warfarin, phenytoin)
- However, increased free fraction leads to increased clearance
- Increased penetration across blood-brain barrier
Metabolism
Reduced liver mass and reduced ____ metabolism
- Prolonged half life, higher steady state concentrations of some drugs (eg. diazepam, metoprolol, phenytoin)
- Unchanged conjugative metabolism in liver
- Decreased ____ blood flow
- Affects drugs with high hepatic extraction ratio, reducing first pass metabolism and increasing drug concentration (eg morphine, verapamil)
Excretion
- Reduced glomerular filtration rate affects drugs like ____ (i.e gentamicin)
- Reduced tubular function reduces active tubular excretion of drugs like beta-lactam antibiotics
- Increased susceptibility to nephrotoxic drugs such as _____
- Acute illness (with dehydration) can rapidly reduce renal clearance
- Important in drugs with narrow margin between therapeutic and toxic dose (e.g. ____ )
Reduced eGFR (i.e reduced renal clearance)
Reduced Liver Mass and Metabolic capacity
Reduced skeletal muscle mass and increased body fat:water ratio
Absorption
- Increased gastric emptying time, which reduces oral bio-availability
- Increased gastric pH with reduced gastric acid secretion (even if not taking PPI), which decreases breakdown of enteric coatings (decreases absorption); increases absorption of some drugs (eg methyldopa)
- Decreased active transport mechanisms in the gut for calcium, folate, vitamin B12
Distribution
- Reduced skeletal muscle mass with increased ratio body fat to water
- Volume of distribution for water soluble drugs decreases, increasing serum concentration (e.g. paracetamol, digoxin)
- Volume distribution for fat soluble drugs increases, leading to prolonged half-life and more toxicity (e.g. diazepam, amiodarone, verapamil)
- Decreased albumin levels
- Increased free fraction of highly albumin-bound drugs (e.g. warfarin, phenytoin)
- However, increased free fraction leads to increased clearance
- Increased penetration across blood-brain barrier
Metabolism
Reduced liver mass and reduced oxidative metabolism
- Prolonged half life, higher steady state concentrations of some drugs (eg. diazepam, metoprolol, phenytoin)
- Unchanged conjugative metabolism in liver
- Decreased portal venous blood flow
- Affects drugs with high hepatic extraction ratio, reducing first pass metabolism and increasing drug concentration (eg morphine, verapamil
Excretion
- Reduced glomerular filtration rate affects drugs like aminoglycosides (i.e gentamicin)
- Reduced tubular function reduces active tubular excretion of drugs like beta-lactam antibiotics
- Increased susceptibility to nephrotoxic drugs such as ACE-I/ARB, diuretics, NSAIDs
- Acute illness (with dehydration) can rapidly reduce renal clearance
- Important in drugs with narrow margin between therapeutic and toxic dose (e.g. digoxin)
Resources for prescribing in the elderly?
STOPP/START criteria
*NB - STOPP criteria is indicated in BNF but not START*
Look in the Cautions section For STOPP criteria related to single drugs or drug classes • Where criteria relate to a drug class without a class monograph, look in the relevant treatment summaries.
Pharmacodynamic changes in the elderly
Increased susceptibility to drug toxicity
Anti-cholinergic side-effects of tricyclic antidepressants such as constipation and confusion
- Increased adverse effects with anticoagulants
- Frequency of bleeding events increases with age
- Increased sensitivity to opiates (by about 50%)
- Increased sensitivity to CNS depressants (eg. propofol)
Reduced Homeostatic Mechanisms
- Postural hypotension in response to vasodilators
- Combination of diminished baroreceptor reflexes and impaired cardiac conduction increases susceptibility to _bradyarrhythmias and hypotensio_n in response to verapamil and diltiazem
Which drugs should be avoided in the elderly where possible?
NSAIDS
Benzodiazepines
Anti-cholinergics
Tricyclic Antidepressants
Glibenclamide (causes hypoglycaemia)
Doxasozin (adrenergic antagonist - BPH)
Which phenotyoical frailty assessment score can be used to assess a patients frailty on acute admission to the hospital?
Remember frailty can be assessed by 4 major main themes:
Cumulative
Phenotypical
Surrogates
“Eyeball”
Bournemouth Criteria:
> 90 - automatically frail
Age: 75-89 - 2 of the following to be considered frail:
Immobility
Incontinence
Cognitive impairment (i.e dementia/delirum - does not include learning disabilities)
Instability (i.e falls)
Iatrogenesis (i.e polypharmacy - > 5 drugs)
*65-75 - need to be instituionalised (nursing/residential home)
A comprehensive geriatric assessment includes which team members and which domains of assessment?
Patient/ Their care giver and
- Doctors • Nurses
- Therapy (OT/PT/Nutrition/swallow etc)
- Social services
- Community services
- Pharmacist
*CGA is not a form but a process of accumulating data on patient by all team members*
Includes:
- Physical Assessment (illness/pain/incontinence/nutrition?ADL’s etc)
- Psychological (Sleeping/Mental Health/Alcohol)
- Social
- Medication review
These domains all inform care plan for patient.
Which medication is contraindicated with Sildenafil (Viagra) concurrent use?
Nitrates
Sildenafil is a PDE5 inhibitor which enhances the effect of nitric oxide and thus leads to vasodilation of the peripheral vasculature leading to a drop in the blood pressure in a similar way to how nitrates work. When taken together the effect is compounded and has led to several deaths in the 1990s.
A 72 year old woman with Parkinson’s disease is managed with Ropinirole (a _____ ). Which is the most important side effect to monitor for?
Dopamine agonist
Impulsivity
Due to the fact that Ropinirole is a dopamine agonist, it can lead to impulsivity. This can then lead to pathological gambling and hypersexuality, which can be a very devastating side effect for patients with Parkinson’s and their families to manage.
What is the pharmacological treatment of Alzheimer’s disease?
Acetylcholinesterase inhibitors aka anti-cholinesterases:
Donepezil - mild
Rivastigmine/Galantamine - moderate
Memantine (NMDA antagonist) - severe or Achesterase inhibitor contraindication
If you have Alzheimer’s disease, your cells can make too much glutamate. When that happens, the nerve cells get too much calcium, and that can speed up damage to them. NMDA receptor antagonists make it harder for glutamate to “dock” – but they still let important signals flow between cells.
A useful mnemonic to remember the features of Alzheimer;s is the ‘4As’:
Amnesia (recent memories lost first)
Aphasia (word-finding problems, speech muddled and disjointed)
Agnosia (recognition problems)
Apraxia (inability to carry out skilled tasks despite normal motor function)
Associated with visual loss, these patients often describe smaller versions of real life objects commonly of faces or cartoons.
Importantly, they realise that the hallucinations are not real. It is thought that this is due to damage of the visual system itself and is not a mental health disorder. Unfortunately there are little treatments or support to offer besides from reassurance of the patient’s sanity.
This is called ____ syndrome.
Charles Bonnet Syndrome
The common conditions leading to the syndrome are age related macular degeneration, followed by glaucoma and cataract.
The imagery is varied and may include groups of people or children, animals, and panoramic countryside scenes.
___ is type of corticosteroid mainly used for its mineralocorticoid properties leading to sodium retention and effective blood volume and therefore pressure.
Indications include orthostatic intolerance and adrenal insufficiencies. Notable side effects include oedema due to fluid retention, hypokalemia and supine hypertension.
Fludrocortisone
_____
Also known as depressive dementia, this is an important differential in the elderly, severe depression can lead to psycho-motor slowing, memory impairment and difficulties in concentration similar to dementia in appearance. These patients often present with self neglect and significant weight loss as a result.
Pseudo-dementia
Haloperidol is contraindicated in patient’s with ____ due to the fact that it promotes dopamine blockade. This can result in ____ and a deterioration in motor function.
Parkinson’s disease
Psychosis
This patient is suffering from Lewy body dementia, evidenced by the fact that she has presented with dementia, fluctuating cognition and mild features of Parkinsonism.
The criteria for diagnosing Lewy body dementia is the presence of dementia alongside two of the three (2/3) core features:
- Fluctuating attention and concentration
- Recurrent well-formed visual hallucinations
- Spontaneous Parkinsonism.
Lobar pneumonia pattern is much less common than bronchopneumonia and is caused by which organism?
Streptococcus Pneumonia (aka pneumococcus)
Empyema is a collection located in the ____ whereas an abscess is in the lung parenchyma.
Pleura
‘_____’ lung is the name given to end stage ILD - much like cirrhosis in the liver
‘Honeycomb’ lung
Polypharmacy can be defined as ____ or more medicines used daily.
5 or more medicines used daily
- Threshold can vary from ≥2 and ≥11 medications
- In children, the accepted definition is 2 or more medicines
Causes of acute confusion?
D - Drugs and Alcohol (Anti-cholinergics, opiates, anti-convulsants, recreational)
E - Eyes, ears and emotional
L - Low Output state (MI, ARDS, PE, CHF, COPD)
I - Infection
R - Retention (of urine or stool)
I - Ictal
U - Under-hydration/Under-nutrition
M - Metabolic (Electrolyte imbalance, thyroid, wernickes
(S) - Subdural, Sleep deprivation
Dementia
Typically progressive clinical syndrome of deteriorating mental function significant enough to \_\_\_\_\_
Affects memory, thinking, orientation, comprehension,
calculation, learning capacity, language and judgement.
• Diagnosis – requires impairment in > than ___ cognitive domains
(memory, language, behaviour and visuospatial/executive
function) significant enough to affect ADLs that can’t be
explained by another cause (eg condition or medications)
Interfere with activities of daily
living (ADLs)
2+
Most common types of dementia:
- ____ (50-75%)
- _____ (up to 20%)
- _____ (10-15%)
- _____(2%)
Alzheimer’s
Vascular
Lewy body
Frontotemporal
• Other (rarer) causes – list not exhaustive
Parkinson’s disease
Associated with Down’s Syndrome (prevalence may be up to 75% aged >=60)
Huntington’s disease
Management of Dementia
Conservative management:
- Environmental modification as previous
- Cognitive stimulation/ cognitive rehab/ group reminiscence therapy/ OT (mild to moderate)
Medical management (largely for Alzheimers or Lewy Body dementia):
https://www.bmj.com/content/bmj/suppl/2018/06/27/bmj.k2438.DC1/Dementia_v19_web.pdf
o Acetylcholinesterase inhibitors:
donepezil (mild), rivastigmine or galantamine (moderate)
o Glutamate antagonists: eg memantine (severe or with C/I to Ach inhibitors)
• Limited role for antipsychotics (haloperidol)
• Future development: Aducanumab: monoclonal antibody: targets amyloid build up
Licensed in US only June 2021
Frailty Management
• Gold Standard: Comprehensive Geriatric Assessment: MDT
approach holistic assessment considering physical issues, function,
environment/ support, _mobility and balanc_e, psychological issues
and medication. Care plans can be put in place
- Exercise interventions: core strength, flexibility, balance, endurance training
- Good nutrition, considering total protein intake, calcium and vitamin D
- Role for BMI reduction? Raised BMI associated with poor outcomes
• Medication reviews
• Advance care planning
Drugs particularly associated with adverse outcomes in
frailty
• Anticholinergics: unsteadiness, blurred vision, dry mouth,
urinary retention, confusion
• Benzodiazepines: falls, regular use increases all-cause
mortality, confusion
• Opioids: constipation, falls, delirium
• NSAID: AKI and gastric ulceration
• Antihypertensives: AKI, falls
What measures should be taken to reduce the risk of delirium during an admission?
- Ensure team of healthcare professionals who are familiar to the person at risk.
- Avoid moving people within and between wards; worth reflecting on the realityof hospital care and the difficulty in achieving this.
- Specialist MDT assessment and personalised care plan. Liaison geriatrics / joint care.
- Appropriate lighting and clear signage / a clock and a calendar should also be easily visible.
- Re-orientate frequently.
- Facilitate regular visits from family and friends.
- Address dehydration and / or constipation.
- Avoid unnecessary catheterisation / lines / restrictions.
- Encourage mobility and keep mobile / active when able.
- Assess for pain, including non-verbal clues of pain and address pain adequately.
- Carry out a medication review.
- Encourage good nutritional intake
- Ensuring hearing and visual aids are available to and used by people who need them, and that they are in good working order.
- Promote good sleep patterns and sleep hygiene.
- Consider alcohol withdrawal regime.
Be vigilant for withdrawal symptoms and
treat if required.
_____ artery ischaemia/infarction results in lateral pontine syndrome, a condition similar to the lateral medullary syndrome but with additional involvement of pontine cranial nerve nuclei.
Anterior Inferior Cerebellar
cranial nerves - 5,6,7,8 - expect ipsilateral facial paralysis or hearing loss - as labyrinthine artery is branch of AICA.
_____ (______ ) causes ipsilateral Horner’s syndrome (ptosis/meiosis/anhidrosis), ipsilateral loss of _____ on the face, and loss of pain and temperature sensation over the _____ body. This syndrome is caused by ischaemia/infarction to _____ artery that supplies the cranial nerves to the medulla
Wallenberg’s syndrome (lateral medullary syndrome) - or posterior inferior cerebellar artery (PICA)
pain and temperature sensation
contralateral
Posterior inferior cerebellar artery (PICA)
Thus
*AICA - causes lateral pontine syndrome (CN 5,6,7,8)
*PICA - causes lateral medullary syndrome (makes sense as medulla is below pons)
_____/ _____ syndrome (paramedian branches of the upper basilar and proximal posterior cerebral arteries): causes an _____ nerve palsy and contralateral hemiparesis.
Weber’s syndrome/medial midbrain
Ipsilateral oculomotor (CN3) - sits right above midbrain just beside posterior cerebral artery and posteromedial basilar arteries.
Webers syndrome- causes an ipsilateral oculomotor nerve palsy (i.e down and out) and contralateral hemiparesis
*Again makes sense as Posterior cerebral artery is above pons and medulla and thus serves the midbrain
_____ is defined by: a pure motor stroke, pure sensory stroke, sensorimotor stroke, or ataxic hemiparesis.
There should be NO:_____ , _____ , or ____
These strokes affect small deep perforating arteries, typically supplying _____ or _____ .
A lacunar infarct (LACI)
higher cerebral dysfunction, brainstem dysfunction.
internal capsule or thalamus
A lacunar stroke (LACS) is a subcortical stroke that occurs secondary to small vessel disease. There is no loss of higher cerebral functions (e.g. dysphasia).
CT scans are useful for detecting haemorrhagic strokes, but can be normal in the first ____ of an ischaemic stroke. ____ can confirm early ischaemic stroke, which appears bright.
Few hours
Diffusion-weighted MRI
A total anterior circulation infarct (TACI) is defined by:
Contralateral hemiparesis or hemiplegia, AND
Contralateral homonymous hemianopia, AND
Higher cerebral dysfunction (e.g. aphasia, neglect)
A TACI involves the anterior AND middle cerebral arteries on the affected side.
*Hemiparesis is a mild or partial weakness or loss of strength on one side of the body. Hemiplegia is a severe or complete loss of strength or paralysis on one side of the body.
A total anterior circulation infarct (TACI) is defined by:
Contralateral hemiplegia or hemiparesis,
AND
Contralateral homonymous hemianopia,
AND
Higher cerebral dysfunction (e.g. aphasia, neglect)
A TACI involves the anterior AND middle cerebral arteries on the affected side.
What is the actue management of Ischaemic Stroke?
Patients should be approached in the DR ABCDE manner.
Airway protection (in patients presenting with depressed consciousness) and aspiration precautions (in patients presenting with swallowing impairment) are very important.
Subsequent stroke management depends on whether the stroke is ischaemic or haemorrhagic. CT head should be performed on arrival to the emergency department to distinguish ischaemic from haemorrhagic stroke. (The most sensitive test for confirming ischaemic infarct is a diffusion weighted MRI. This is generally used if the diagnosis is unclear but is not normally possible in the emergency setting due to logistical challenges)
Alteplase (tissue plasminogen activator) is indicated in patients presenting within 4.5 hours of symptom onset and with no contraindications to thrombolysis (e.g. recent head trauma, GI or intracranial haemorrhage, recent surgery, acceptable BP, platelet count, and INR).
Mechanical Thrombectomy can be performed in patients with anterior circulation strokes within 6 hours of symptom onset, provided that they have a good baseline functional status and lack of significant early infarction on initial CT scan. Mechanical Thrombectomy can also be performed in posterior circulation strokes up to 12 hours after onset.
If hyper-acute treatments are not offered, patients should receive aspirin 300 mg orally once daily for two weeks. If hyper-acute treatments are offered (i.e thrombolysis or Thrombectomy), aspirin is usually started 24 hours after the treatment and following a repeat CT Head that excludes any new haemorrhagic stroke.
Anterior Cererbral Artery Strokes are most likely to cause ____ and ____ weakness (due to the motor homunculus).
The anterior cerebral arteries supply the medial and supero-medial edge of the cortex, along the falx cerebri.
Lesions of the ACA would cause foot and lower leg weakness, and are less likely to cause speech disturbance (patients can repeat sentences but struggle to initiate). ACA lesions can also causes a sensory loss of the lower limb
https://www.youtube.com/watch?v=5j1MsyJeLmc
MDT Management of Falls in the Elderly
- Analgesia titration to allow mobility.
- Orthopaedic support, but likely non-surgical (“conservative”) management.
- Delirium risk reduction (Lighting/clock/continuation of staff).
- Medication review - hold ACEi / beta-blocker / alpha blocker with low B.P.
-
Multi-factorial falls assessment, including gait and balance / lying and standing B.P / medication review / Alert technology whilst inpatient, certainly patient activated “call bell” for assistance but with dementia consider automated system such as a falls alert mat / consider “bay tag” observation
with cognitive impairment. - Treat other co-morbidities (for example, constipation,pneumonia)
- Patient education with falls risk.
- Further cardiac monitor (ECG)
- Further falls risk assessment as MDT as part of discharge planning including:
o Medication review when lying and standing B.P are known.
o Gait and balance specialist assessment and balance and strengthening exercise programme and review walking aids.
o Environmental review with interventions.
o Vitamin D supplementation - check levels, fragility fracture / osteoporosis secondary prevention.
o Assistive technology (falls sensor for possible future falls to alert and avoid “long lie”).
Which tools can be used to identify non-specific cognitive dysfunction?
And which tool can be used to specifically assess for delirium?
Non-specific
MOCA
MMSE
10/4 AMT
6-CIT
Delirum Specific
4AT
How do you assess capacity?
Assume capacity unless patient gives you reason to doubt
