Is testing the voice under sedation reliable in medialization thyroplasty?

Area of Science:

• Otolaryngology
• Anesthesiology
• Speech Science

Background:

• Medialization thyroplasty is a surgical procedure to correct unilateral vocal cord palsy.
• Surgeons often adjust prosthesis depth based on intraoperative voice monitoring.
• Current practice recommends sedation over general anesthesia for this procedure.

Purpose of the Study:

• To objectively quantify the effects of sedation and patient positioning on voice during medialization thyroplasty.
• To determine if sedation is a justified anesthetic approach for this surgery.

Main Methods:

• A prospective study involving 15 adult patients undergoing medialization thyroplasty.
• Voice recordings were analyzed in three conditions: seated (no sedation), supine (no sedation), and supine (with sedation).
• Sedation involved midazolam, fentanyl, and propofol, with monitored sedation levels.

Main Results:

• Sedation significantly altered voice pitch and acoustic parameters, including jitter and shimmer.
• Specific findings showed higher pitch and jitter/shimmer values, and lower harmonics-to-noise ratio under sedation.
• Patient position (seated vs. supine) did not significantly influence voice outcomes.

Conclusions:

• Sedation demonstrably influences voice quality, complicating intraoperative vocal assessment.
• General anesthesia with intraoperative fibrolaryngoscopy or no sedation are proposed as alternatives.
• The findings question the routine use of sedation for medialization thyroplasty voice monitoring.