What is the recommended approach for paediatric total intravenous anaesthesia (TIVA) using target-controlled infusion (TCI)?

Paediatric Total Intravenous Anaesthesia and Target-Controlled Infusion

For paediatric total intravenous anaesthesia (TIVA), target-controlled infusion (TCI) using propofol with remifentanil is the recommended approach, with age-appropriate pharmacokinetic models and continuous monitoring of depth of anaesthesia to optimize outcomes and minimize complications. This approach provides excellent control of anaesthesia depth while reducing the risk of awareness, PONV, and facilitating rapid recovery.

Key Components of Paediatric TIVA-TCI

Drug Selection and Administration

• Primary agents:

  • Propofol as the hypnotic agent
  • Remifentanil as the short-acting opioid 1

• Pharmacokinetic models:

  • For propofol: Absalom or Kataria parameter sets are most commonly used 2
  • For remifentanil: Minto parameter set is recommended 2

• Administration technique:

  • Open-loop TCI system where the physician selects target concentrations
  • Computer-controlled infusion pumps programmed with paediatric pharmacokinetic parameters
  • Target either plasma concentration or effect-site concentration 3

Dosing Guidelines

For children aged 1-12 years:

• Initial propofol target: 4-6 μg/ml (plasma concentration)
• Maintenance propofol target: 3-4 μg/ml
• Remifentanil: 2-8 ng/ml (effect-site concentration)

For infants (birth to 2 months):

• Higher clearance rates require increased infusion rates
• Remifentanil 0.4-1.0 μg/kg/min 1
• Additional bolus doses may be required but should be used cautiously

Monitoring Requirements

• Essential monitoring:

  • Processed EEG monitoring (BIS or Entropy) to prevent awareness 4, 2
  • Target BIS values between 40-60 3
  • Standard cardiorespiratory monitoring
  • Neuromuscular monitoring if muscle relaxants are used

• Special considerations:

  • More vigilant monitoring for:
    • Infants under 1 year
    • Children with low body weight
    • Patients with hemodynamic instability

Clinical Applications and Benefits

• Advantages of paediatric TIVA-TCI:

  • Rapid onset and offset of action
  • Reduced PONV compared to inhalational techniques 3
  • Smooth emergence from anaesthesia
  • Ability to maintain spontaneous ventilation when required
  • Avoidance of pollution in the operating room 5

• Ideal scenarios for TIVA-TCI:

  • Day-case procedures requiring rapid recovery
  • ENT and ophthalmic surgery
  • Procedures requiring neurophysiological monitoring
  • Patients with susceptibility to PONV 3
  • Repeated diagnostic or therapeutic procedures 5

Safety Considerations and Pitfalls

• Potential complications:

  • Risk of awareness if infusion is interrupted
  • Propofol infusion syndrome with prolonged high-dose administration
  • Respiratory depression requiring careful titration

• Avoiding complications:

  • Use dedicated IV line for TIVA drugs
  • Ensure visibility of infusion site
  • Implement safety checks for TCI equipment
  • Have backup anaesthesia plan in case of IV access issues
  • Use processed EEG monitoring, especially with neuromuscular blockade 2

• Special populations requiring caution:

  • Infants under 1 year (require experienced practitioners) 5
  • Children with cardiovascular instability
  • Patients with difficult IV access

Practical Implementation

1. Pre-anaesthesia preparation:

   • Secure reliable IV access
   • Prepare TCI pumps with appropriate models
   • Set up EEG monitoring

2. Induction:

   • Start with propofol TCI at 4-6 μg/ml
   • Add remifentanil TCI at 4-6 ng/ml
   • Titrate to clinical effect

3. Maintenance:

   • Adjust propofol target to maintain BIS 40-60
   • Adjust remifentanil based on surgical stimulation
   • Consider supplemental regional anaesthesia for postoperative analgesia 3

4. Emergence:

   • Reduce remifentanil concentration 5-10 minutes before end of surgery
   • Reduce propofol concentration gradually
   • Ensure alternative analgesia is established before TIVA discontinuation 1

TIVA-TCI in paediatrics requires proper education and clinical experience to be administered safely. The use of processed EEG monitoring is particularly important to prevent awareness during administration in difficult clinical situations, including patients with low body weight, obesity, or when using neuromuscular blocking agents 4.