Automatic Remifentanil Administration Guided by ANI During Propofol Anesthesia (ANI-LOOP)

Automatic Remifentanil Administration Guided by the Analgesia Nociception Index During Propofol Anesthesia

Prospective Randomized Monocentric Clinical Trial during propofol anesthesia. The aim of the study is to test whether the use of a medical device designed to automatically administer remifentanil during surgery based on expert rules and continuous reading of heart rate, blood pressure and the Analgesia Nociception Index results in lower overall remifentanil administration versus standard practice.

Prospective Randomized Monocentric Clinical Trial during propofol anesthesia. inclusion: ASA 1, 2 or 3 adult patients scheduled to undergo burn wound surgery in a Burn Center (University Hospital of Lille, France) arm 1 : Remifentanil will be automatically administered by an expert system guided by heart rate, blood pressure and the Analgesia Nociception Index (ANI). arm 2 : Remifentanil will be administered by a target controlled device using the Minto pK/pD model. propofol is administered throughout the procedure with a target controlled device using the pK/pD model of Schnider. The target will be guided by the BiSpectral index values. primary endpoint : overall normalized remifentanil administration. secondary endpoints : relative amount of time spent in a state of hemodynamic reactivity ; relative amount of time the ANI spends in the [0-50], [50-70] and [70-100] windows ; relative amount of time the BIS spends in the [0-40], [40-60] and [60-100] ; hemodynamic status at various times during anesthesia ; total amount of target modifications of remifentanil and propofol ; total amount of morphine administered in PACU ; total amount of ketamine administered in PACU ; incidence of nausea/vomiting in PACU ;

Monocentric prospective randomized controlled clinical trial arm 1: medical device automatically administering remifentanil, guided by expert rules and continuous reading of heart rate, blood pressure and Analgesia Nociception Index (MDMS, Loos, France) arm 2 : standard practice : remifentanil is administered using a target controlled device using a pK/pD model of Minto

arm 1 : remifentanil is automatically administered by a medical device using expert rules and continuous reading of heart rate, blood pressure and Analgesia Nociception Index (MDMS, Loos, France)

arm 2: remifentanil is administered by a target control device using Minto's remifentanil pK/pD model. This is standard practice for this type of surgery at the Burn Center of the University Hospital of Lille, France.

experimental medical device using expert rules and continuous reading of heart rate, blood pressure and Analgesia Nociception Index for automatic remifentanil administration

Remifentanil Ce target can range from 0 to 10 ng.ml-1. Remifentanil target is adapted in order to maintain Analgesia Nociception Index (MDMS, Loos, France) in the [50-70] range.

propofol is used for induction and maintenance of general anesthesia using Schnider pK/pD model. Propofol Ce target is adapted in order to maintain BiSpectral Index in [40-60] range

ANI (Analgesia Nociception Index) value is used in the "std_practice" arm for guidance of the remifentanil Ce target

relative amount of time during which heart rate or SBP exceed 120% of baseline, or heart rate drops below 40/min, or SBP drops below 75 mmHg.

5 min before start of nociception, 5 min after start of nociception and 20 min after start of nociception

Visual Analog Scale every 15 min in PACU The pain VAS is a continuous scale comprised of a horizontal (HVAS) or vertical (VVAS) line, usually 10 centimeters (100 mm) in length, anchored by 2 verbal descriptors, one for each symptom extreme (0, 10).

Inclusion Criteria: ASA 1, 2 or 3 adult patients scheduled to undergo burn wound surgery at the Burn Center of the University Hospital of Lille Exclusion Criteria: BMI outside [17 - 35 kg/m2] pregnancy or breast feeding women non sinus cardiac rhythm documented dysautonomia complicated diabetes mellitus known allergy to a drug used in the clinical trial