Monitored Anesthesia Care with Target-Controlled Infusion in Vibroplasty

Abstract

Objectives: Correct positioning of a floating mass transducer during middle ear implant surgery is often problematic. With the use of monitored anesthesia care (MAC), however, deep sedation is maintained during surgery, followed by conscious sedation in which the patient can respond to test questions that investigate correct device position and function. The main aim of this study was to determine whether intraoperative audiometric assessment was feasible with MAC with target-controlled infusion in vibroplasty. An additional aim was to determine whether MAC was sufficiently comfortable for patients during the procedure. Methods: The study group comprised 8 patients who underwent vibroplasty under sedation. Before suturing, audiometric assessment was done by stimulating the external auditory processor with pure tones at 0.5, 1, 2, and 4 kHz. Blood pressure, arterial oxygen saturation level, heart rate, and end tidal carbon dioxide level were monitored during the procedure and at awakening. Results: Audiometric assessment was successfully completed in all 8 patients. The selected parameters indicated that no patient experienced pain or discomfort during surgery; the absence of discomfort was confirmed 1 to 2 hours after the operation by simple questioning. Conclusions: We found MAC to be an efficient and relatively safe technique for verifying the correct coupling of the floating mass transducer with the middle ear during vibroplasty. The patients were able to respond appropriately to questions and commands; moreover, none reported having experienced pain or discomfort during the operation.