Fully Automated Anesthesia, Analgesia and Fluid Management
Condition: General Anesthetic Drug Overdose; Adverse Effect of Intravenous Anesthetics, Sequela; Complication of Anesthesia; Drug Delivery System Malfunction; Hemodynamic Instability; Underdosing of Other General Anesthetics
MeSH terms: Drug Overdose
Study type: Interventional
Phase: Phase 1

Summary: 
      Evaluate the feasibility and quality of automated anesthesia, analgesia and fluid management
      based on a combination of several physiological variables (bispectral index [BIS], stroke
      volume [SV], and stroke volume variation [SVV]) using 2 independent physiologic closed-loop
      systems (PCLS) in patients undergoing high risk vascular surgery
    

Detailed description: 
      Evaluate the feasibility and quality of automated anesthesia, analgesia and fluid management
      based on a combination of several physiological variables (bispectral index [BIS], stroke
      volume [SV], and stroke volume variation [SVV]) using 2 independent physiologic closed-loop
      systems (PCLS) in patients undergoing high risk vascular surgery.

      All patients will receive total intravenous anesthesia in target controlled infusion mode
      using the population pharmacokinetic sets of Schnider for propofol and Minto for remifentanil
      to target the effect-site concentration. Infusion Toolbox 95 version 4.11 software (Free
      University of Brussels, Brussels, Belgium) implemented in a personal computer serving as a
      platform for: calculating effect-site concentrations of propofol and remifentanil; displaying
      effect-site concentration estimates in real time; providing a user interface that permits
      entry of patients' demographic data (sex, age, weight, and height) and modifications to
      target concentrations; controlling the propofol and remifentanil infusion pumps (Alaris
      Medical, Hampshire, United Kingdom); and recording calculated effect-site drug
      concentrations.

      All patients will receive a baseline crystalloid infusion (PlasmaLyte, Baxter, Belgium)
      delivered by a pump at a rate of 3 mL/ kg/h (Fresenius Kabi, Belgium). Additional fluid was
      given using a goal-directed fluid therapy protocol guided by the cardiac output monitor
      (EV-1000; Edwards Lifesciences) and consisted of 100 mL boluses (Voluven, Fresenius Kabi,
      Germany) delivered by our PCLS (Learning Intravenous Resuscitator [LIR]). For fluid output, a
      Q-Core Sapphire Multi-Therapy Infusion Pump (Q-Core, Israel) was controlled by the LIR using
      software provided by Q-Core via a serial connection (Commands Server R.01). If hypotension
      occurred (defined as mean arterial pressure <20% of baseline blood pressure) and no fluid is
      delivered by the LIR, it will be treated by the anesthesiologist using a vasopressor drug.

      In this pilot study, each closed loop also will operate independently, guided only by its own
      respective inputs (BIS for the propofol; SV and SVV for the fluid boluses).

      The investigators will also measure analgesia using the PhysioDoloris monitoring device
      (MDoloris Medical Systems, Lille, France).
    

Intervention name(s): BIS XP, Covidien, Ireland; EV-1000 TM, Edwards Lifesciences, Irvine, California, USA
Intervention type(s): Other; Other
Intervention description(s): Closed loop for propofol and remifentanil using BIS XP TM, Covidien, Ireland; Closed loop for fluid perfusion using EV-1000 TM, Edwards Lifesciences, Irvine, CA, USA
Other intervention name(s): bispectral index
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: closed loop; remifentanil; propofol