Automated Anesthesia Guided by the Conox Monitor for Surgery (Conox-loop)

Comparison Between Manual Versus Closed-loop Titration of Propofol and Remifentanil Guided by the qCon and qNox Indexes During Induction and Maintenance of General Anesthesia in Adult Patients: a Multicentre Randomized Controlled Study

This study compares automated administration of propofol and remifentanil versus manual administration during general anesthesia for a surgery. The closed-loop coadministration of propofol and remifentanil is guided by qCon and qNox indexes from the Conox monitor.

Study Overview

• Status: Terminated
• Conditions: Anesthesia, General
• Intervention / Treatment: Device: Closed loop anesthesia; Drug: Propofol; Drug: Remifentanil

Detailed Description

Several monitors are currently proposed to evaluate the depth of hypnosis. The Conox monitor differentiates itself from the other brain monitor by calculating two EEG indexes, the qCon and the qNox. The qCon corresponds to the depth of the sedation and the qNox relates to the probability that a nociceptive stimulation triggers a movement of the patient. A controller allowing the automated titration of propofol guided by the qCon and remifentanil guided by the qNox has been developed. In preparation for a large multi-center control trial, this prospective randomized study evaluates the effectiveness of such a closed-loop anesthesia system. Two groups of patients are compared: one arm in which propofol and remifentanil are administered by the anesthesiologist using target-controlled infusion (TCI) systems, and the second arm in which propofol and remifentanil are administered automatically by the combined closed-loop anesthesia system. In both groups, the goal is to maintain qCon between 40 and 60, the recommended range during anesthesia by the manufacturer. It is expected the combined closed-loop anesthesia system group to do similar or better control to maintain the qCon in the desired range.

• Study Type: Interventional
• Enrollment (Actual): 62
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Bourgogne-Franche-Comté
    • Besançon, Bourgogne-Franche-Comté, France, 25030
      • Service d'Anesthésie Réanimation Chirurgicale, CHU Besançon
  • Ile De France
    • Suresnes, Ile De France, France, 92151
      • Service d'Anesthésie, Hôpital Foch
  • Poitou-Charentes
    • Soyaux, Poitou-Charentes, France, 16800
      • Service d'Anesthésie du Centre Clinical

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Scheduled surgery for at least one hour
• Consent for participation
• Affiliation to the social security system

Exclusion Criteria:

• Pregnant or breastfeeding women
• Patients for which Conox monitor should not be used
• Allergies to propofol or remifentanil

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Full automation group; Full automation control of propofol and remifentanil	Device: Closed loop anesthesia; Propofol and Remifentanil are administered automatically using a closed-loop system. The goal of this study is to compare manual titration versus automated titration of propofol and remifentanil in adult patients undergoing surgery guided by the electro-cortical activity. The aim in both group is to maintain the qCon in the range 40-60 during induction and maintenance of general anesthesia using the propofol in TCI mode. But also the qNox in the range 40-60 using remifentanil. The controller is based on a Proportional-Integral-derivative algorithm which steers a target to the pumps during induction and maintenance of general anesthesia.; Drug: Propofol; The dosage is modified automatically by the device or according to the new medical prescription.; Drug: Remifentanil; The dosage is modified automatically by the device or according to the new medical prescription.
Other: Control group; Manual control of of propofol and remifentanil using TCI system	Drug: Propofol; The dosage is modified automatically by the device or according to the new medical prescription.; Drug: Remifentanil; The dosage is modified automatically by the device or according to the new medical prescription.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adequate sedation	Percentage of time with qCon index within the 40-60 range as recommended by the manufacturer of Conox monitor. Data from the Conox monitor (signal quality index, qCon index, qNox index, Suppression ratio) are recorded every second.	Start of general anesthesia maintenance, i.e. qCon below 60 for 30 consecutive seconds for the first time, until the end of propofol et remifentanil infusion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adequate analgesia	Percentage of time with qNox index within the 40-60 range as recommended by the manufacturer of Conox monitor.	Start of general anesthesia maintenance, i.e. qNox below 60 for 30 consecutive seconds for the first time, until the end of propofol et remifentanil infusion
Occurrence of Burst Suppression Ratio (bsr)	Presence of Burst Suppression defined by a rate > 10% for at least one minute	Intraoperative period
Dose of hypnotic drug	Total amount of propofol during the induction and the maintenance of the anesthesia	Intraoperative period
Dose of analgesic drug	Total amount of remifentanil during the induction and the maintenance of the anesthesia	Intraoperative period
Medical interventions on the dosage of drugs	Number of modifications of target of propofol and remifentanil	Intraoperative period
Hemodynamic status	Number of episodes of hemodynamic anomalies having required a treatment	Intraoperative period
Fluid therapy	Intraoperative volume loading and transfusion	Intraoperative period
Delay before awakening	Delay between the cessation of infusion of propofol and remifentanil and extubation	12 hours
Explicit memorization	Awareness standardized questionnaire	48 hours

Collaborators and Investigators

• Sponsor: CMC Ambroise Paré

Publications and helpful links

General Publications

• Liu N, Chazot T, Hamada S, Landais A, Boichut N, Dussaussoy C, Trillat B, Beydon L, Samain E, Sessler DI, Fischler M. Closed-loop coadministration of propofol and remifentanil guided by bispectral index: a randomized multicenter study. Anesth Analg. 2011 Mar;112(3):546-57. doi: 10.1213/ANE.0b013e318205680b. Epub 2011 Jan 13.
• Jensen EW, Valencia JF, Lopez A, Anglada T, Agusti M, Ramos Y, Serra R, Jospin M, Pineda P, Gambus P. Monitoring hypnotic effect and nociception with two EEG-derived indices, qCON and qNOX, during general anaesthesia. Acta Anaesthesiol Scand. 2014 Sep;58(8):933-41. doi: 10.1111/aas.12359. Epub 2014 Jul 4.

Study record dates

Study Major Dates

• Study Start (Actual): July 2, 2018
• Primary Completion (Actual): February 18, 2019
• Study Completion (Actual): February 18, 2019

Study Registration Dates

• First Submitted: May 6, 2018
• First Submitted That Met QC Criteria: May 17, 2018
• First Posted (Actual): May 30, 2018

Study Record Updates

• Last Update Posted (Actual): November 5, 2021
• Last Update Submitted That Met QC Criteria: October 28, 2021
• Last Verified: October 1, 2021

More Information

Terms related to this study

• Keywords: EEG monitoring; Total intravenous anesthesia; Anesthesia, general; Closed loop anesthesia; Conox; qCon; qNox
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anesthetics, Intravenous; Anesthetics, General; Anesthetics; Analgesics, Opioid; Narcotics; Hypnotics and Sedatives; Remifentanil; Propofol
• Other Study ID Numbers: 2017/04

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No