Lecture 7 - elderly Flashcards
describe physiology and ageing of elderly people
considerable variability. individualist assessment and targets
loss of total body water and muscle mass - increase in body fat
presentation/ signs/ symptoms may change
describe physiological changes affecting absorption
physiological changes - increase gastric pH or decrease GI mobility and blood
clinical effects are no clinical effect on the majority of drugs. calcium requires acidic environment for optimal absorption. enter-coated medication forms with increased gastric pH.concurrent use of antacids or PPIs might affect absorption
what are physiological changes affecting volume of distribution.
reduced body water has an effect of reduced volume of distribution for hydrophilic drugs fro example, lithium
reduced lean body mass has reduced volume of distribution for drugs that binds t muscles eg digoxin
increased body fat increases volume of distribution for lipophilic drugs eg diazepam and trazodone
reduced album increases amount in percentage of unbound or free drug eg warfarin and phenytoin
what are physiological changes affecting metabolism
first pass metabolism is decreased by 1% per annum in people aged over 40 years which causes an increase expected effect
metabolic clearance of drugs by the liver may be reduced by a reduction in blood flow, and decreases CYP450 system and decrease liver size and mass
what are phase I and phase II reactions and their effect
phase I reactions (oxidation, reduction, hydrolysis) has an effect of conversion to metabolites of lesser or equal or greater effect for example, diazepam and theophylline
phase II reactions has an effect of conversion to inactive metabolites such as lorazepam and temazepam
what are physiological changes affecting elimination ?
decreased size of the kidneys
reduced renal blood flow
reduced numbers of functional nephrons
decreased tubular secretion
all which lead to reduced glomerular filtration rate
what is delirium and what are potential causes ?
delirium is th acute deterioration in metal functioning triggered mainly by acute medical illness, surgery, trauma or drugs
potential causes drugs: urianry retention; infection; pain; severe constipation; dehydration
what are common medicines associated with falls ?
Commonly implicated drugs/drug groups…
- Sedatives: benzodiazepines, z-drugs
- Alpha-blockers/ACE-inhibitors: hypotension
- Drugs inducing electrolyte disturbances or dehydration
what are anticholinergic medicines adverse effects ?
ADR: dry mouth, constipation, urinary retention, hypotension, drowsiness, impaired cognition, balance …falls
