physiolgy of pain Flashcards
What provides elimination of pain?
Analgesic drug- eg lidocaine
What is the aim of analgesia?
Elimination of pain
Haemostasis
What gives reduction in haemorrhage?
Vasoconstrictor- epinephrine/ felypressin
What else does the vasoconstrictor do?
Prolongs activity of drug
Reduces toxicity
What items of the nerve contribute to conduction?
Nodes of ranker
End feet synapse
What do the nodes of ranvier do?
Ionic exchange of pain impulses
Allows impulse to jump along length of fibre
Effects the speed of the impulse
Analgesic solution gains access as nodes
What do chemical transmitters do?
Transmit impulses from end feet of neurone to dendrites of the next
Name chemical transmitters
Noradrenaline
Serotonin
Gamma amino butyric acid
Dopamine
What conditions give rise to pain?
Inflammation
Trauma
Necrosis
Ischaemia
Name pain producing substances produced by injured tissues
Potassium
Sodium
Chloride
Calcium
Name the phases of impulse conduction
Polarisation Depolarisation Action potential Repolarisation Resting
What happens at polarisation?
No pain
Potassium in cytoplasm
Soldium outside
What happens at de polarisation
Destruction of polarity
Ionic exchange
Sodium on inside
Potassium on outside
What happens at action potential
Change in membrane potential permeability
Allows transference of ions
Potassium exchanges with sodium
What occurs at Repolarisation?
.
Achieved by sodium potassium pump
Reverts ions to polarised state
