Pain Flashcards
Defin
Unpleasant sensory and emot experience assoc with actual or poten tiss dam
Acute- recent onset, lim durat, ID cause
Chronic- after healing, over 3mnth, maybe no ID cause
What pt says
Nociception
Unconc transmiss painful stim
fibres
A delta- sharp pain
C- dull pain
Modulation
Brain- paracetamol, opioid, water therapy, hypnosis, personality.
SC- TENS, opioid, capsaicin, LA
Periph- NSAID, LA
Pyramid
Go up with incr, chronic or CA pain
Go down if acute, breakthrough, or sev chronic
Not really apply to post op pain
Non opioid- paracetamol, NSAID
Weak opioid ADDED- tramadol, codeine
Storng opioid- morphine, diamorphine, buprenorphine, al/remi/fentanyl, pethidine
paracetamol
COX inhib maybe Can give IV, v effec Antipyretic Caution in liver fail, under 50kg Acetylcysteine for OD
NSAID
Inup, diclofenac, parocoxib, ketorolac, asp, naproxen
Usef for inflammatory pain
Anti pyretic
Caution in renal fail, bleeding, fluid reten, bronchospasm, GI disturb
Asp also used for- preven thromb, pre eclampsia, essen thrombocythemia.
MOA- block COX1 and 2, prev pg and thromboxane format. Reduces stom lining protec, prevs clotting, prevs pain fever and inflamm.
CI- allergy, renal impair, hypovol, coag defect, asthma, preg, breast feed.
Ibup can give over 1yo, asp over 12 only
weak opioid codeine
Widely avail Variable metab, enx dep Resp dep Constipation MOA- stim opiod Rs Oral or IM NOT FOR KID Codeine and oramorph not controlled
weak opioid tramadol
Powerful Avail IV Constipation Caution in eld eg sedat,hallucin Oral, IM, IV Inhibs na and 5HT3 repupt Can interact with SSRI and TCA, and ondansetron. Lowers seiz thresh
Strong opioids
Remifentanyl, alfentanyl, fentanyl- short acting, used as aneas
Morphine, diamorhpine, oxycodone, oxynorm- longer acting
Morphine predictable effect
S/e- constip, RD, NV, sedat, itching
Adjuncts
Clonidine
Ketamine
LA infus- regional, wound, IV
Gabapentin- prevs acute to chronic
Central neuroaxial methods
Spinal block- sub arach CSF, LA lasts 3 hr, diamorphine lasts 8hr post op
Epidural catheter- infusion LA and opioid.
But these 2 can reduce mobil
Tap and N blocks often favoured
Femoral N block for NoF, with strong opioids
PCA
48mg morphine syringe in 4hr, 1mg bolus, 5 min lock out
Plasma levs vary less, usually req less
High satis
Reduc stress and wait
s/e mx
Give anti emetic as req- RF fem, motion sickn, non smoker
Always have written up prn
As with laxatives if over couple days
Pain mx
Non pharm- env, posit, distrac, hypnosis, acupunc, TENS, heat
Inhalat- entonox
LA- topical EMLA and ametop, SC, periph N block, central
Sys active drug- pyramid
Sedative- BDZs, ketamine, chloral hydrate
Dis specif- horms, antispasmodic eg buscopan, chemo, radio, surg
