Analgesia in Oral Surgery Flashcards
what drugs can we prescribe for pain in dentistry
aspirin
ibuprofen
diclofenac
dihydrocodeine
carbamazepine
paracetamol
what is the arachidonic pathway of pain
trauma and infection lead to breakdown of membrane phospholipids producing arachidonic acid
this can be broken down to form prostaglandins
these sensitise tissues to other inflammatory products which results in pain
what is the action of prostaglandins
sensitise tissues to other inflammatory products such as leukotrienes
what are the properties of aspirin
analgesic
antipyretic
antiinflammatory
metabolic
what is the mechanism of action of aspirin
inhibits COX1 and COX2 to reduce production of prostaglandins
what does COX1 inhibition do
reduce platelet aggregation
what is the analgesic action of aspirin
peripheral action predominates
results from inhibition of prostaglandin synthesis in inflamed tissues
what is the antipyretic properties of aspirin
prevents the temperature raising effects of IL1 and rise in brain prostaglandin levels so reduces elevated temperature in fever
what is the antiinflammatory action of aspirin
as they inhibit production of prostaglandins (which are vasodilators) they can reduce redness and swelling
what are the adverse effects of aspirin
GIT problems
hypersensitive
overdose - tinnitus, metabolic acidosis
aspirin burns - mucosal
how does aspirin cause GIT problems
as prostaglandins inhibit gastric acid secretion and increase blood flow through gastric mucosa and help production of mucin cells
aspirin stops this by inhibiting prostaglandin secretion
what hypersensitivity reactions can occur due to aspirin
acute bronchospasm/asthma attacks
skin rashes/urticaria
what would overdose of aspirin present as
hyperventilation
tinnitus, deafness
vasodilation and sweating
metabolic acidosis
coma
how does aspirin cause mucosal burns
due to salicylic acid
how do you prevent mucosal aspirin burns
make sure aspirin is taken with water
what are the groups to avoid when prescribing aspirin
peptic ulcers
epigastric pain
bleeding abnormalities
anticoagulants
pregnant/breast feeding
patients on steroids
renal/hepatic impairment
under 16s
asthma
allergies to other NSAIDs
taking other NSAIDs
elderly
why should people on anticoagulants avoid aspirin
it enhances warfarin and other coumarin anticoagulants as it displaces warfarin from binding sites of plasma proteins and increases free warfarin
why should pregnant people not take aspirin
increased risk of haemorrhage
increased risk of jaundice in baby
prolong/delay labour
why should patients on steroids avoid taking aspirin
25% of steroid patients will develop peptic ulcer
aspirin can result in perforation of the ulcer
where is aspirin metabolised and excreted
metabolised in liver
excreted in kidney
with regards to the kidneys, what might inhibition of renal prostaglandin result in
sodium retention
reduced renal blood flow
renal failure
what is reye’s syndrome
fatty degenerative process in liver causing profound swelling in the brain
when is aspirin completely contraindicated
children and adolescents under 16
previous or active peptic ulceration
haemophilia
hypersensitivity to aspirin or any other NSAID
what is the prescription for aspirin
aspirin dispersible tablets 300mg
two tablets four times daily, preferably after food for five days