[Closed-loop titration of propofol guided by the bispectral index]. / Titration automatisée du propofol guidée par l'index bispectral.

This review analyzes the clinical studies concerning the automated perfusion, or closed-loop, of propofol guided by the bispectral index (BIS). To carry out the maintenance of general anaesthesia by a closed loop propofol-BIS is feasible as shown by studies comprising few low risk patients. We showed that induction of anaesthesia is feasible with a closed loop, haemodynamic stability being similar to a manual titration. A second study, bearing on the whole of the anaesthesia of patients ASA I to III undergoing very diverse surgical acts, showed that the closed loop propofol-BIS was more precise than a manual perfusion. This confirms that the closed loop propofol-BIS is not an esoteric research and that it represents a tool with a future for the clinician.

Feasibility of closed-loop titration of propofol guided by the Bispectral Index for general anaesthesia induction: a prospective randomized study.

BACKGROUND: This study was designed to evaluate the feasibility of propofol infusion by a closed-loop system for the titration of anaesthetic induction guided by Bispectral Index. METHODS: Forty patients were prospectively and randomly allocated into two groups: the target control infusion (TCI) group, where propofol titration was performed manually guided by the Bispectral Index using a commercial pharmacokinetic model (Diprifusor device) and the closed-loop group where titration was performed using a proportional differential algorithm. For both groups, the objective was to achieve a Bispectral Index of 50. Remifentanil TCI was infused at a target of 2 ng mL-1 and was maintained constant throughout the study. Feasibility of automatic induction was evaluated with performance error and haemodynamic data. RESULTS: Bispectral Index overshoot (-9 +/- 13% vs. -16 +/- 20%, P = 0.035) and mean duration of induction (381 +/- 106 s vs. 490 +/- 131 s, P = 0.004) were lower in the closed-loop group than in the TCI group. Haemodynamic data were similar between groups with a similar use of ephedrine bolus. CONCLUSION: The system was able to allow induction clinically for all patients. Automated titration guided by Bispectral Index for propofol infusion was feasible without increase in haemodynamic adverse effects.