The Accuracy and Clinical Feasibility of a New Bayesian-Based Closed-Loop Control System for Propofol Administration Using the Bispectral Index as a Controlled Variable

BACKGROUND: Closed-loop control of the hypnotic component of anesthesia has been proposed in an attempt to optimize drug delivery. Here, we introduce a newly developed Bayesian-based, patient-individualized, model-based, adaptive control method for bispectral index (BIS) guided propofol infusion into clinical practice and compare its accuracy and clinical feasibility under direct observation of an anesthesiologist versus BIS guided, effect compartment controlled propofol administration titrated by the anesthesiologist during ambulatory gynecological procedures. METHODS: Forty ASA patients were randomly allocated to the closed-loop or manual control group. All patients received midazolam 1 mg IV and alfentanil 0.5 mg IV before induction. In the closed-loop control group, propofol was administered using the previously described closed-loop control system to reach and maintain a target BIS of 50. In the manual control group, the propofol effect-site concentration was adapted at the discretion of the anesthesiologist to reach and maintain a BIS as close as possible to 50. Induction characteristics, performance, and robustness during maintenance and recovery times were compared. Hemodynamic and respiratory stability were calculated as clinical feasibility parameters. RESULTS: The closed-loop control system titrated propofol administration accurately resulting in BIS values close to the set point. The closed-loop control system was able to induce the patients within clinically accepted time limits and with less overshoot than the manual control group. Automated control resulted in beneficial recovery times. Our closed-loop control group showed similar acceptable clinical performance specified by similar hemodynamic, respiratory stability, comparable movement rates, and quality scores than the manual control group. CONCLUSIONS: The Bayesian-based closed-loop control system for propofol administration using the BIS as a controlled variable performed accurate during anesthesia for ambulatory gynecological procedures. This control system is clinical feasibility and can be further validated in clinical practice.

[1]  I J Rampil,et al.  Automated anesthesia: fact or fantasy? , 2001, Anesthesiology.

[2]  Michel M. R. F. Struys,et al.  Estimation of Optimal Modeling Weights for a Bayesian-Based Closed-Loop System for Propofol Administration Using the Bispectral Index as a Controlled Variable: A Simulation Study , 2007, Anesthesia and analgesia.

[3]  J. Bruhn,et al.  Pharmacodynamic Interaction between Propofol and Remifentanil Regarding Hypnosis, Tolerance of Laryngoscopy, Bispectral Index, and Electroencephalographic Approximate Entropy , 2004, Anesthesiology.

[4]  Detection.  The sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) , 1997 .

[5]  K. Leslie,et al.  Closed loop control of sedation for colonoscopy using the Bispectral Index* , 2002, Anaesthesia.

[6]  S. Shafer,et al.  The Influence of Method of Administration and Covariates on the Pharmacokinetics of Propofol in Adult Volunteers , 1998, Anesthesiology.

[7]  Steven L Shafer,et al.  Using the Time of Maximum Effect Site Concentration to Combine Pharmacokinetics and Pharmacodynamics , 2003, Anesthesiology.

[8]  M. Struys,et al.  Comparison of Plasma Compartment versus Two Methods for Effect Compartment–controlled Target-controlled Infusion for Propofol , 2000, Anesthesiology.

[9]  A. Absalom,et al.  Closed-loop control of propofol anaesthesia using bispectral index: performance assessment in patients receiving computer-controlled propofol and manually controlled remifentanil infusions for minor surgery. , 2003, British journal of anaesthesia.

[10]  Manfred Morari,et al.  Modeling and closed-loop control of hypnosis by means of bispectral index (BIS) with isoflurane , 2001, IEEE Transactions on Biomedical Engineering.

[11]  Michel M R F Struys,et al.  Performance Evaluation of Two Published Closed-loop Control Systems Using Bispectral Index Monitoring: A Simulation Study , 2004, Anesthesiology.

[12]  D. Bogen,et al.  The Use of Computers for Controlling the Delivery of Anesthesia , 1992, Anesthesiology.

[13]  A. Absalom,et al.  Closed-loop Control of Anesthesia Using Bispectral Index: Performance Assessment in Patients Undergoing Major Orthopedic Surgery under Combined General and Regional Anesthesia , 2002, Anesthesiology.

[14]  R. Pirracchio,et al.  Feasibility of closed‐loop titration of propofol guided by the Bispectral Index for general anaesthesia induction: a prospective randomized study , 2006, European journal of anaesthesiology.

[15]  M. Morari,et al.  Multitasked closed-loop control in anesthesia , 2001, IEEE Engineering in Medicine and Biology Magazine.

[16]  M. Struys,et al.  Comparison of Closed-loop Controlled Administration of Propofol Using Bispectral Index as the Controlled Variable versus “Standard Practice” Controlled Administration , 2001, Anesthesiology.

[17]  M. Hara,et al.  PROPOFOL ACTIVATES THE GABAA RECEPTOR-IONOPHORE COMPLEX IN DISSOCIATED HIPPOCAMPAL NEURONS OF THE RAT , 1992 .

[18]  G N Kenny,et al.  Closed-loop control of propofol anaesthesia. , 1999, British journal of anaesthesia.

[19]  Steven L. Shafer,et al.  Measuring the predictive performance of computer-controlled infusion pumps , 1992, Journal of Pharmacokinetics and Biopharmaceutics.

[20]  L B Sheiner,et al.  Forecasting individual pharmacokinetics , 1979, Clinical pharmacology and therapeutics.

[21]  Henry R. Black,et al.  The sixth report of the Joint National Committee on the Detection, Evaluation, and Treatment of High Blood Pressure , 1998 .

[22]  L C Sheppard,et al.  Therapeutic Uses of Sodium Nitroprusside and an Automated Method of Administration , 1978, International Anesthesiology Clinics.

[23]  Reginald G. Bickford,et al.  Automatic electroencephalographic control of general anesthesia , 1950 .

[24]  S L Shafer,et al.  The influence of age on propofol pharmacodynamics. , 1999, Anesthesiology.

[25]  A Iliadis,et al.  Application of Bayesian estimation for the prediction of an appropriate dosage regimen of amikacin. , 1989, Journal of pharmaceutical sciences.

[26]  Rolf Wymann,et al.  A New Closed-Loop Control System for Isoflurane Using Bispectral Index Outperforms Manual Control , 2004, Anesthesiology.