Can Adequacy of Anesthesia Depth and Quality of Recovery be Influenced by the Level of Neuromuscular Blockade?

Phase 4

Completed

Brief Summary: The investigators hypothesize that an anesthetic protocol maintaining deep neuromuscular block throughout the entire surgical procedure followed by sugammadex reversal, would suppress EMG activity and result in improved anesthetic stability by reducing the variability of the Bispectral Index of the EEG, and be beneficial by reducing the total doses of the anesthetic drugs propofol and remifentanil required to maintain an adequate level of anesthesia (BIS between 40 and 60).

Recruitment & Eligibility

Inclusion Criteria

Patients ASA I-III
Between 18 - 80 years old
Scheduled for routine cervical surgery
Minimum duration of surgery is 90 minutes and performed with total intravenous anaesthesia (TIVA) with the hypnotic propofol, the analgesic remifentanil and the neuromuscular relaxant rocuronium
Patients that are able to and do provide a signed informed consent form

Exclusion Criteria

Patients with neuromuscular diseases and severe cardiac and respiratory pathologies
Contra indication for any of the drugs used
Not able to complete the baseline PQRS test.
Indication to perform tracheal intubation using fibroscopy
Patients who are pregnant or nursing

Arm && Interventions

Group	Intervention	Description
Deep NMB group	Rocuronium	Deep Neuromuscular Block group - with a standard rocuronium dose for intubation (0.6 mg/kg), followed by a constant infusion of rocuronium (10-15 ug/kg/min) to guarantee a PTC less or equal to 2 on the TOF monitor (PTC is evaluated every 5 minutes). The reversal of neuromuscular block is performed with Sugammadex (4 mg/kg).
Deep NMB group	Sugammadex	Deep Neuromuscular Block group - with a standard rocuronium dose for intubation (0.6 mg/kg), followed by a constant infusion of rocuronium (10-15 ug/kg/min) to guarantee a PTC less or equal to 2 on the TOF monitor (PTC is evaluated every 5 minutes). The reversal of neuromuscular block is performed with Sugammadex (4 mg/kg).

Primary Outcome Measures

Name	Time	Method
BIS Signal Variability Using the Measured Standard Deviation During the Maintenance Phase of Anesthesia	Maintenance of anesthesia, an average of 130 minutes	BIS (Bispetral Index of the EEG) sample standard deviation during the maintenance phase of anesthesia was used as a measure of signal variability, maintenance phase is defined as the time between the first time the BIS signal drops below 60 after loss of consciousness, until the time the BIS signal goes above 60 after the propofol infusion is stopped. BIS signal varies between 0 to 100. BIS values near 100 represent an "awake" clinical state while 0 denotes the maximal effect an isoelectric EEG. The aim was to maintain the BIS value within a target range of 40 to 60. The higher the BIS sample standard deviation the higher the oscillation around the sample mean.
Required Effect-site Concentrations of Propofol and Remifentanil	Maintenance of anesthesia, an average of 130 minutes	Mean effect-site concentration of propofol required during maintenance of anesthesia (using target controlled infusion). Mean effect-site concentration of remifentanil required during maintenance of anesthesia (using target controlled infusion).

Secondary Outcome Measures

Name	Time	Method
PQRS Results at 15 and 40 Minutes After Surgery (Taking Into Account the Patient Baseline Values of the PQRS Test Done on the Preanesthetic Visit)	15 and 40 minutes after surgery	PQRS(Post-operative Quality Recovery Scale) recovery rate at 15 minutes post surgery and PQRS recovery rate at 40 minutes post surgery. Recovery is defined as returning to PQRS baseline values.
PQRS Satisfaction Results at Day 3 After Surgery	3rd day after surgery	Patient satisfaction with anesthetic care rated as: Not satisfied, A little satisfied, Moderately satisfied ,Satisfied, Totally Satisfied