Simple Analgesia

Paracetamol

  • Paracetamol given pre- and intraoperatively reduces PONV and improves analgesia, but does ont reduce opioids
  • Reduces PONV when given IV
    Effect is independent of its reduction in opioid requirements.

NSAIDs

  • Renal injury is low when used appropriately
  • All NSAIDs sit on a spectrum of activity between COX-1 and COX-2
  • Non-selective NSAIDs:
    • Are associated with ↑ risk of minor and major bleeding
    • May precipitate bronchospasm in susceptible patients
  • COX-2 inhibitors do not:
    • Impair platelet function
      Blood loss is reduced compared to non-selective NSAIDs and comparable to placebo after TKR.
    • Precipitate bronchospasm
    • Appear to ↑ rates of gastric ulceration when used in short courses (5-7 days)
    • Affect bone healing in humans
  • Cardiac risk is:
    • Slightly greater with COX-2s
    • Appears dose-related
    • ↑ in patients without diagnosed cardiac disease
    • Naproxen and celecoxib have lower risks of myocardial injury than other NSAIDs

References

  1. Schug SA, Palmer GM, Scott DA, Alcock M, Halliwell R, Mott JF; APM:SE Working Group of the Australian and New Zealand College of Anaesthetists and Faculty of Pain Medicine (2020), Acute Pain Management: Scientific Evidence (5th edition), ANZCA & FPM, Melbourne.