What is the ideal anesthetic technique for induction of tracheal resection and anastomosis?

Ideal Anesthetic Technique for Induction of Tracheal Resection and Anastomosis

Total intravenous anesthesia (TIVA) with remifentanil, propofol, and ketamine while maintaining spontaneous ventilation is the ideal anesthetic technique for induction of tracheal resection and anastomosis. 1, 2

Pre-induction Considerations

• Thorough airway assessment is critical as these patients often have compromised airways due to stenosis or tumor involvement 3
• Antisialogogue administration (glycopyrronium bromide 0.2-0.4 mg IM 30-60 minutes pre-procedure or 0.1-0.2 mg IV 3-5 minutes pre-procedure) to reduce secretions and improve visualization 4
• Adequate topicalization of the airway with lidocaine (maximum dose 9 mg/kg lean body weight) to facilitate awake bronchoscopy and reduce coughing reflexes 4
• Position patient appropriately, typically in a ramped position to optimize airway access 4

Induction Technique

• Maintain spontaneous ventilation to prevent airway collapse, especially important in cases of tracheal stenosis 1, 2
• Administer 100% oxygen for pre-oxygenation for 3-5 minutes using a well-fitting mask with a closed circuit 4
• Initiate TIVA with:
  • Remifentanil: Start at 0.05-0.1 mcg/kg/min and titrate to effect 5, 2
  • Propofol: Target-controlled infusion or standard infusion titrated to clinical effect 2
  • Ketamine: Initial dose of 1-2 mg/kg IV administered slowly over 60 seconds 6, 1
• Avoid muscle relaxants to maintain spontaneous breathing and prevent airway collapse 1, 2

Airway Management During Induction

• Consider awake flexible bronchoscopy to assess the stenosis and guide intubation 4
• When performing awake tracheal intubation, use a two-point check to confirm correct tube placement:
  1. Visualization of the tracheal lumen with flexible bronchoscopy
  2. Confirmation with capnography 4
• For rigid bronchoscopy, maintain spontaneous assisted ventilation (SAV) throughout the procedure 1

Maintenance of Anesthesia

• Continue TIVA with remifentanil (0.05-0.2 mcg/kg/min), propofol, and intermittent ketamine as needed 5, 1, 2
• Monitor depth of anesthesia to maintain adequate sedation while preserving spontaneous breathing 2
• Titrate remifentanil to suppress cough reflexes while maintaining respiratory drive 5, 2

Extubation Strategy

• Plan extubation carefully as these patients are at high risk for complications 4
• Consider using an airway exchange catheter (AEC) for "at-risk" extubation:
  • Insert lubricated AEC through the tracheal tube to a predetermined depth (never beyond 25 cm in adults)
  • Remove the tracheal tube over the AEC
  • Keep AEC in place until confident that reintubation will not be necessary 4
• Alternatively, consider the Bailey maneuver (laryngeal mask exchange) if appropriate:
  • Insert deflated LMA behind the tracheal tube
  • Ensure correct LMA placement
  • Inflate LMA cuff
  • Deflate tracheal tube cuff and remove while maintaining positive pressure 4
• For deep extubation (if appropriate):
  • Ensure adequate depth of anesthesia
  • Deflate the tracheal tube cuff
  • Apply positive pressure via the breathing circuit and remove the tracheal tube
  • Maintain airway patency until the patient is fully awake 4

Common Pitfalls and How to Avoid Them

• Avoid neuromuscular blocking agents which can lead to complete airway collapse in patients with significant tracheal stenosis 1, 2
• Prevent coughing during induction and emergence which can disrupt the anastomosis site - use adequate remifentanil infusion to suppress cough reflexes 5, 2
• Avoid excessive positive pressure ventilation which may damage the surgical repair 4
• Monitor for and be prepared to treat hemodynamic instability, particularly hypotension from TIVA agents 4, 7
• Have emergency equipment readily available including rigid bronchoscopy equipment and surgical airway kit 4

By maintaining spontaneous ventilation with TIVA using remifentanil, propofol, and ketamine, you can provide optimal conditions for tracheal resection and anastomosis while minimizing risks of airway collapse and surgical complications.