What are the recommendations for using armoured (endotracheal tube with a wire reinforcement) vs standard endotracheal tubes for Functional Endoscopic Sinus Surgery (FESS) septoplasty?

Armoured vs Standard Endotracheal Tubes for FESS/Septoplasty

For functional endoscopic sinus surgery (FESS) and septoplasty, standard polyvinyl chloride (PVC) endotracheal tubes are recommended over armoured (wire-reinforced) tubes, as the surgical field does not require the specific advantages of armoured tubes and these procedures carry lower risk of tube kinking compared to neurosurgical cases with extreme neck positioning.

Rationale for Standard Tubes in FESS/Septoplasty

Surgical Positioning Considerations

• FESS and septoplasty are performed with the patient supine and the head in neutral or slight extension, which does not create the extreme neck flexion that predisposes to tube kinking 1
• The surgical approach is entirely intranasal/endoscopic, meaning the endotracheal tube connector location is not in the surgical field and does not interfere with surgeon access 2, 3
• Standard PVC tubes provide adequate airway protection for these procedures without the specific complications associated with armoured tubes 1

Disadvantages of Armoured Tubes

• Armoured tubes are susceptible to perforation and partial obstruction from patient biting, which can occur during emergence from anesthesia 4
• The wire reinforcement, while preventing external compression, does not prevent internal obstruction from biting forces 4
• Armoured tubes are more expensive than standard PVC tubes without providing additional benefit in procedures where extreme positioning is not required 1

When Armoured Tubes Are Indicated

Specific Clinical Scenarios

Armoured (flexometallic) tubes should be reserved for cases with:

• Extreme neck flexion during neurosurgical procedures where standard PVC tubes would kink from over-bending 1
• Prolonged prone positioning where external compression of the tube is likely 1
• Shared airway procedures where the tube must be positioned away from the surgical field (though this does not apply to FESS/septoplasty) 5

Practical Recommendations for FESS/Septoplasty

Tube Selection

• Use a standard cuffed PVC endotracheal tube for routine FESS and septoplasty procedures 6
• Monitor cuff pressure and maintain below 20-25 cm H₂O to prevent tracheal mucosal injury 6, 7
• Ensure proper tube size selection using length-based resuscitation tapes for pediatric patients or standard sizing for adults 7

Positioning and Securing

• Position the head in neutral or slight extension to optimize surgical access without creating risk of tube kinking 1
• Secure the tube with tape or commercial holder, avoiding compression of neck vessels 5
• Document tube depth at the teeth/gums and verify position with waveform capnography 5

Aspiration Prevention

• Elevate the head of bed 30-45 degrees when feasible to reduce aspiration risk during emergence 8
• Clear secretions from above the endotracheal tube cuff before deflation and extubation 6

Common Pitfalls to Avoid

• Do not routinely use armoured tubes for FESS/septoplasty simply because they are available—they offer no advantage and carry specific risks 1, 4
• Avoid over-securing the tube in a way that creates neck flexion, as this could theoretically increase kinking risk even with standard tubes 1
• Monitor for tube obstruction during emergence, particularly if the patient begins biting (this risk is actually higher with armoured tubes) 4
• Re-verify tube position after any repositioning of the patient's head during the procedure 5