Laryngeal microsurgery under deep neuromuscular block

Patients are randomized in two group using minimization For both groups patients are in dorsal position with classical monitoring. Preoxygenation Local of glottis 2mg/kg lidocaine Ventilation with high frequencies jet ventilation driving pressure between 1.5 and 3 bar, respiratory rate 150/min and report I/T 30% Surgeons will not be aware of the group to which the patient belongs. Automatic and continuous recording of vital parameters by Philips monitoring. In particular, monitoring of neuromuscular function by the NMT module (Acceleromyography by hand with TOF-tube: calibration, supra-maximal stimulation of the ulnar nerve by train-of-four (TOF) every 15 seconds and recording of muscle responses in the protocol of anesthesia according to the recommendations of the literature Group non curare, anesthesia induction 1. lidocaine 1mg/kg intravenous bolus 2. remifentanyl 0.5 µg/kg/min at the start and 0.15 µg/kg/min during the surgery continuous intravenous 3. propofol mode Target controlled intravenous anaesthesia to adapt according to the depth of anesthesia 4. solumedrol 2mg/kg bolus intravenous After the disappearance of the ciliary reflex and spontaneous ventilation, an assisted manual ventilation test is performed: The patient is manually ventilated until it is deep enough. Bi-spectral index <60. Placement of eye protection. The surgeon exposes the glottal in apnea and evaluates its facility: easy, difficult or inexposable + duration of installation and his vision of vocal cords: o, ¼ post, ½ post, ¾ post or entire. With the installation of the laryngoscope performed, the surgeon places the Mayne-Remacle metal catheter in infraglottic and the high frequency type ventilation starts: The quality of the operating conditions will be evaluated from the first visualization of the operative field and every 5 minutes in different ways: - Evaluation of the operating conditions by the surgeon (4 grades excellent, acceptable, to improve and unacceptable). An unacceptable operating condition in the group will require improvement of analgesia (increase of remifentanyl concentration by 0.15 ± 0.25 µg/kg/min), anesthesia (increase of propofol concentrations) and if conditions remain unacceptable to curarise rocuronium 0.6mg/kg. - Cough within 5 min: present / absent - Vocal cords position (abduction, adduction) - Vocal cords movement during the 5 minutes: yes-no. - Measurement of the glottal surface via the same optics (0) for all procedures. Calibrated measurement via the use of a palpator allowing a perfectly objective measurement. -SpO2 every 5 minutes. The continuous infusion of remifentanyl is stopped 5 minutes before the end of the procedure. The metal catheter is removed at the end of the surgical procedure and at the same time the propofol administration is stopped. Assisted manual ventilation is used to reduce end tidal CO2 <45 and allow the patient to recover his spontaneous rythm.