General anaesthesia for thyroplasty

Anesthetic Technique and Functional Outcomes in Modified Montgomery Thyroplasty

BACKGROUND

Montgomery thyroplasty type I is a surgical technique indicated in vocal cord paralysis which consists of the paralyzed cord medialization, improving the voice quality. The objective of the study is to describe in detail the anesthetic method to obtain optimal post-medialization voice results.

METHODOLOGY

Retrospective case series study including patients who underwent medialization thyroplasty using the modified Montgomery technique at the General University Hospital of Valencia between 2011 and 2021. The anesthetic technique consisted of general anesthesia with neuromuscular relaxation and a laryngeal mask. Pre- and post-surgical vocal functional data of maximum phonation times (MPT), G score, and Voice Handicap Index-30 (VHI-30) were evaluated.

RESULTS

All the patients presented an improvement in voice results, increasing MPT after surgery and a decrease in VHI-30 and G score postoperatively, with statistically significant differences between the pre- and post-surgical results (p-value < 0.05). There were no complications related to anesthesia or surgery.

CONCLUSIONS

The use of general anesthesia with muscle relaxation in modified Montgomery thyroplasty may be a good option to consider. The use of a laryngeal mask for ventilation combined with a fiberoptic check allows direct visualization of the vocal cords intraoperatively, providing good functional voice results.

Dexmedetomidine sedation for laryngeal framework surgery

OBJECTIVES

Sedation for laryngeal framework surgery has lacked easy modulation between appropriate pain control, airway protection, and the alertness appropriate for vocal testing. Our objective was to determine whether dexmedetomidine hydrochloride could safely and effectively be used as the sole intravenous anesthetic agent in conjunction with local anesthesia for laryngeal framework procedures.

METHODS

We undertook a prospective review of 14 patients who underwent laryngeal framework surgery with dexmedetomidine anesthesia in 2004 and 2005. All dexmedetomidine doses, sedation levels, and vital signs, including blood pressure, heart rate, respiratory rate, and oxygen saturation level, were recorded every 15 minutes by the anesthesiologist throughout the duration of the procedures. Operative conditions were noted by the surgeon, focusing special attention on airway protection, patient arousability, and patient comfort.

RESULTS

Dexmedetomidine sedation produced hemodynamic and respiratory values that were maintained near preoperative values, and overall pharyngeal-laryngeal integrity provided superior operating conditions for the patient and the operating surgeon.

CONCLUSIONS

We believe that dexmedetomidine provides excellent sedative and operative conditions for awake laryngeal framework procedures. Coupled with local anesthesia, dexmedetomidine produced virtually no undesirable hemodynamic or respiratory effects, while allowing for adequate sedation the majority of the time. The operative conditions were markedly improved over those of previous standard monitored anesthesia regimens.

Efficacy of total intravenous anesthesia without intubation for laryngeal framework surgery

CONCLUSION

Total intravenous anesthesia (TIVA) without intubation has the advantages of both conventional general anesthesia and local anesthesia. It is useful in laryngeal framework surgery because intraoperative voice monitoring while the patient remains awake is required.

OBJECTIVE

In laryngeal framework surgery, it is desirable to monitor the voice during surgery. However, surgery is conducted under general anesthesia, although such a procedure renders the patient unable to phonate during surgery. We conducted TIVA without intubation, allowing patients to breathe spontaneously while undergoing operation, and succeeded in intraoperative voice monitoring with satisfactory postoperative voice production.

SUBJECTS AND METHODS

The subjects were 21 patients who underwent surgery. For TIVA, propofol and pentazocine were used as a sedative and analgesic, respectively. A bispectral index (BIS) monitor was used to measure the depth of the anesthesia. Before the vocal folds were to be rotated, propofol administration was interrupted to arouse and instruct the patient to phonate. Guided by the phonation, the vocal folds were correctly positioned. Then propofol administration was resumed, and the wound was closed.

RESULTS

The BIS value during continued administration of propofol was around 60, but exceeded 90 in all patients within 233.6 +/- 64.5 s after cessation. They clearly remembered the conversation they had with us during surgery.

A series of thyroplasty cases under general anaesthesia

Thyroplasty is an operation on the upper airway to improve voice quality in patients with unilateral vocal cord paralysis. It requires access to an uninstrumented larynx and a functional assessment of vocal cord medialization. It is a difficult anaesthetic procedure that requires sharing the airway with the surgeon. We describe an anaesthetic technique to give good operating conditions and a safe airway, using total intravenous anaesthesia, a laryngeal mask airway and intraoperative fibreoptic endoscopic assessment of the larynx, and present a series of 13 patients. Other anaesthetic techniques for thyroplasty are described and discussed.