Premedication

Premedication is useful for:

Anxiolysis

Allaying anxiety is an important part of patient preparation. Strategies include:

  • Pharmacological
  • Non-pharmacological

Pharmacological

Premedication is helpful in children who can’t use logic. Consider:

  • Anxiolysis/sedation
    • Midazolam: 0.5-1 mg/kg PO (up to 15mg)
      Onset with 15-30 minutes.
    • Clonidine 2-4μg/kg PO
      Slower onset than midazolam (>45 minutes). Consider combining with midazolam; e.g. 0.5mg/kg midazolam and 1μg/kg clonidine PO.
    • Temazepam 10-20mg or Diazepam 0.2mg/kg
      For older children, and 45-60 minutes prior to induction.
    • Ketamine 3-6mg/kg PO
      • Avoid as first line agent or without co-administration of benzodiazepine
      • May prolong recovery time
      • Consider in the presence of other behavioural problems

Non-Pharmacological

  • Explanatory booklets
  • Parental presence at induction
    Not appropriate for all parents or all children.
    • Reduces separation anxiety
    • Parental anxiety (and calmness) may be transmitted to the child
    • Requires understanding by the parents about:
      • Induction plan
      • When the parents are to leave
        Need a dedicated member of staff to guide them out.

Skin Preparation

Topical cutaneous anaesthesia is routine prior to venepuncture and cannulation. Options include:

  • Local anaesthetics
    • EMLA cream
      • 2.5% lignocaine and 2.5% prilocaine
      • Cover with an occlusive dressing and leave for 1-2/24
        65% effective after 1/24.
      • Lasts 30-60 minutes folling removal
      • Vasoconstrictor effect at 1.5 hours
    • Tetracaine
      • 4% gel
      • Cover with occlusive dressing
      • Onset within 40 minutes
      • Lasts 4 hours following removal
      • Erythema and local vasodilation
  • Ethyl chloride
    • Solution in glass vial
    • Evaporates on skin contact, causing transient freezing and subsequent anaesthesia
    • Works instantaneously

Analgesia

For minor procedures:

  • 25% sucrose 0.25ml Q2min (up to 1ml, or 0.5ml if < 1500g) for infants

Secretions

Useful in children where secretion control is paramount, including:

  • Cerebral palsy
  • Potential difficult airway
  • High risk of laryngospasm
    • Neonates

Options include:

  • Atropine 40μg/kg PO
    Given ~90 minutes before induction.
  • Glycopyrrolate 100μg/kg PO.
    Given ~1 hour before induction.

References