COTE Flashcards
Define polypharmacy
being prescribed more than FOUR medications
Define pharmacodynamics
how the DRUG interacts with the body
Define pharmacokinetics and the four subtypes
how the BODY affects the drug
- Absorption
- Distribution across body compartments
- Metabolism
- Excretion
What can polypharmacy result in?
- Increased risk of SEs
- Risk of drug-drug interaction
- Therapeutic cascade (as a result of SEs misinterpreted as a new medical condition)
- Risk of meds not being thoroughly reviewed
Why is polypharmacy more common in the elderly?
- Frailty
- Communication problems
- Co-morbidities
- Prescribing for SEs
- Changes in pharmacokinetics:
- Increased % body fat
- Decreased % body water and serum albumin
- Results in increased distribution of fat-soluble
drugs and decreased distribution of water-soluble
drugs - Decreased metabolism with age
- Increased kidney problems (reduced GFR -> reduced excretion of drugs excreted by kidneys, e.g. Digoxin
- Decreased liver volume and enzyme activity (hepatic metabolism of many drugs decreased so the dose should be adjusted to reduce risk of toxicity)
Complications of polpharmacy?
- Increased morbidity and mortality
- Increased hospital stay lengths
- Reduce compliance
- Risk of adverse effects and drug-drug interactions
Define inappropriate prescribing
- prescribing a CI drug
- prescribing for inappropriate dose or duration
- prescribe drug likely to adverseley effect prognosis
- not prescribe a drug that could improve outcomes
how to avoid polypharmacy?
- Regular medication reviews
- Combining medications
- Take a thorough history
Define osteoporosis
Progressive loss of bone mass associated with change in bone micro-architecture
What is bone remodelling
- A normal process continually taking place within bone.
- An essential process that allows bone to adapt to stressors and repair microdamage.
- The net product of bone formation and resorption.
What are the stages of bone remodelling?
- Activation of osteoclasts from circulating precursor cells - medicated by RANK ligand (NF-kB)
- Aggregation and adherence of osteoclasts to regions fo active bone resorption on trabecular plates
- OsteoClastic breakdown of bone matrix -> releasing CALCIUM, MINERALS and ACTIVE GROWTH FACTORS
- OsteoBlastic deposition of OSTEOID with subsequent MINERALISATION as CALCIUM and PHOSPHATE is deposited
What happens in post-menopausal women?
- Shift towards RESORPTION, leading to net bone loss
- Osteoclasts function in less regulated manner -> perforating through trabecular plate
- No framework for osteoblast activity and structural integrity is lost
- Loss of connectivity between trabecular plates is typical of microstructural changes seen in OP
Name an OP risk tool and what it calculates
FRAX: 10-year fracture risk
What are the risk factors for primary osteoporosis?
8
- Female
- Previous fragility fracture
- Maternal history of hip fracture
- Current smoker
- Alcohol intake > 3 units/day
- Glucocorticoids > 3 months > 5mg/day
- Low calcium and vitamin D deficiency
- Low BMI (<19)
What are the causes of secondary osteoporosis?
5
- Rheumatoid arthritis
- Chronic malabsorption/malnutrition (e.g. coeliac)
- Hyperthyroidism/Hyperparathyroidism
- Premature menopause (< 45yrs)
- Chronic liver disease
What investigations might you do if suspected osteoporosis?
- Bloods: FBC/UE/LFT/TFT/Calcium/Phosphate/VitD/PTH/Coeliac serology/myeloma screen
- DEXA Scan: GOLD STANDARD - measures BMD standard deviation from norm.
T-score = average 25yr old; -2.5 = OP
Z-score = age-matched score - Whole spine XR
- Bone turnover markers: serum C-terminal telopeptide (CTX levels)
Pharmacological management for OP? Important things to consider?
- Vitamin D supplements for all with fracture/at risk
- Calcium supplements (dependent on base levels and diet)
- Bisphosphonates:
o Ensure no serious dental issues -> can cause osteonecrosis of the jaw
o CI if CrCl < 30mL/min
o PO alendronic acid if probability > 1% (unless GORD/PUD)
o IV zoledronic acid if probably > 10%, or if oral not tolerated or CI (Oral can be difficult to take as have to take first thing and remain standing for 30 mins)
o Risk of atypical femur fracture so monitor BMD
Lifestyle management for OP?
- Weight-bearing and muscle-strengthening exercises
- Falls prevention
- Smoking cessation and alcohol avoidance
Define syncope
Transient loss of consciousness due to transient global cerebral hypoperfusion characterised by rapid onset, short duration and complete recovery
Epidemiology of syncope?
- Incidence rises over 70yrs of age
- Men are more likely to have a cardiac cause
Syncope differentials?
Loss of consciousness:
- Epilepsy
- Metabolic disorders (hypoxia/hypoglycaemia)
- Intoxication
- Vertebrobasilar TIA
Without LOC:
- Cataplexy
- Drop attacks
- Falls
- Pseudosycnope
Types of cardiac syncope?
Bradycardic: - Sinus node disease - Atrioventricular disease Tachycardic: - Supraventricular - Ventricular Drug-induced: - Antiarrhythmics - Antianginals - Antiemetics - Antipsychotics - Inotropes Cardiac: - Acute MI - Hypertrophic cardiomyopathy - Pericardial disease/tamponade - Congenital abnormalities Others: - Pulmonary embolus - Severe pulmonary HTN - Acute aortic dissection
Treatment for cardiac syncope?
- Stop any drugs that may exacerbate arrhythmias
- Sinus node disease/AV defects -> cardiac pacing
- Ventricular tachycardia -> cardiac catheter ablation/IUD
Define orthostatic hypotension
Within 3 mins of standing:
- Systolic BP drop of 20mmHg (with or without symptoms)
- OR a drop to below 90mmHg on standing even if the drop is less than 20mmHg (with or without symptoms)
- OR diastolic drop of 10 mmHg with symptoms
Occurs as a consequence of impaired vasoconstriction due to chronic impairment of autonomic sympathetic activity
Types of orthostatic syncope?
Drug-induced: - Antihypertensives - Diuretics - Vasodilators - Phenothiazides - Antidepressants Primary autonomic failure: - Pure autonomic failure - Parkinsons (w/autonomic failure) - Multi-system atrophy - Dementia with lewy bodies Secondary autonomic failure: - Diabetes mellitus - Amyloidosis - Spinal cord injury - Uraemia Volume depletion: - Haemorrhage - Diarrhoea - Vomiting - Dehydration
Management of orthostatic syncope?
Discontinue any offending medication if possible
Lifestyle modifications:
- Increase fluid intake
- Counter manoeuvres
- Compressions stockings
Pharmacological:
- Fludrocortisone (mineralocorticoid - increases plasma vol)
- Midodrine (alpha-antagonist - increases BP)
Define reflex syncope?
Transient loss of consciousness due to inappropriate cardiovascular response of vasodilation or bradycardia, cerebral hypoperfusion
Most common cause of syncope!
Types of reflex syncope?
Vasovagal: - Emotional stress (fear/pain) - Orthostatic stress Situational: - Post-prandial - Post-micturition - Cough/sneeze - Post-exercise - Playing a wind instrument - Weight lifting Carotid sinus syndrome
Describe carotid sinus syndrome
- Ventricular pause of > 3 seconds and a fall in systolic BP of > 50 mmHg following carotid sinus massage
- Disease of the autonomic nervous system
- Hypersentivie baroreceptors:
o Cause dilation and drop in BP
o Bradycardia
o Collapse - A form of REFLEX syncope
- Rare before 40 yrs
- Diagnosis with tilt table and carotid massage
- 3 types:
o Cardioinhibitory
o Vasodepressor
o Mixed
Treatment of reflex syncope?
- Physical counter manouevres (knees crossed) at suspected time –> increases BP
- Cardioinhibitory carotid sinus syndrome -> cardiac pacing may be beneficiary
Describe sinus sick syndrome
- Usually cause by sinus node fibrosis
- Sinus node becomes dysfunctional and in some cases slows to the point of sinus bradycardia or sinus pauses
- Diagnose with history, ECG and carotid sinus massage
Describe vascular steal syndrome
- Subclavian artery stenosis
- Means you can’t get blood from subclavian (due to stenosis), so blood is ‘stolen’ from the Circle of Willis instead
- Leads to collapse
What is the STOPP tool?
The Screening Tool of Older Person Prescriptions
- For patients over 65 yrs
Aims to:
- Improve the appropriateness of prescription
- Reduce the occurrence of adverse events
- Reduce drug costs
What is the START tool?
The Screening Tool to Alert doctors of the Right Treatment
- Looks at which medications should be used for certain conditions on patients 65 yrs and older
Which medications may cause urinary incontinence and how might they present?
- Alcohol: Polyuria, frequency, delirium
- ACE-I: Cough and stress incontinence
- Anticholinergic: Urinary retention and overflow
- Diuretic: Polyuria, frequency, urgency
- Opiates: delirium, sedation, constipation and urinary retention
- Tricyclic antidepressants: Urinary retention and overflow
Define stress incontinence
- Sphincter weakness
- Detrusor pressure causes closing press of urethra
- Involuntary leakage on effort or exertion
What are the causes of stress incontinence?
- Menopause (low oestrogen)
- Radiotherapy
- Pelvic surgery
- Congenital weakness
- Vaginal prolapse
- Post-prostatectomy in men
How might stress incontinence present?
- When cough/laugh/lift/exercise/movement
Must exclude overactive bladder via CYSTOMETRY
