Anesthetic Management Using Multiple Closed-loop Systems and Delayed Neurocognitive Recovery: A Randomized Controlled Trial
Alexandre Joosten, M.D., Ph.D.; Joseph Rinehart, M.D.; Aurélie Bardaji, M.D.; Philippe Van der Linden, M.D., Ph.D.; Vincent Jame, M.D.; et alLuc Van Obbergh, M.D., Ph.D.; Brenton Alexander, M.D.; Maxime Cannesson, M.D., Ph.D.; Susana Vacas, M.D., Ph.D.; Ngai Liu, M.D., Ph.D.; Hichem Slama, Ph.D.; Luc Barvais, M.D., Ph.D.
 Author Notes
From the Department of Anesthesiology (A.J., A.B., V.J., L.V.O, L.B.), and Department of Clinical and Cognitive Neuropsychology (H.S.), Erasme Hospital, and Department of Anesthesiology, Brugmann Hospital (P.V.d.L.), Université Libre de Bruxelles, Brussels, Belgium; Department of Anesthesiology and Intensive Care, University of Paris-Saclay, Bicetre Hospital, Le Kremlin-Bicétre, Paris, France (A.J.); Department of Anesthesiology and Perioperative Care, University of California, Irvine, Irvine, California (J.R.); Department of Anesthesiology, University of California, San Diego, San Diego, California (B.A.); Department of Anesthesiology and Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California (M.C., S.V.); Department of Anesthesiology, Foch Hospital, Suresnes, Paris, France (N.L.); and Outcome Research Consortium, Cleveland Clinic, Cleveland, Ohio (N.L.).
Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).
A.J. and J.R. contributed equally to this article.
Submitted for publication January 11, 2019. Accepted for publication September 16, 2019.
Correspondence: Address correspondence to Dr. Joosten: Department of Anesthesiology and Intensive Care, University of Paris-Saclay, Bicetre Hospital, 94270 Le Kremlin-Bicêtre, France. joosten-alexandre@hotmail.com. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Anesthesiology Newly Published on November 5, 2019. doi:10.1097/ALN.0000000000003014

Abstract
Editor’s Perspective:

What We Already Know about This Topic:

Recommendations for anesthetic care are often difficult to implement in the intraoperative setting because of the requirement for continuous attention

What This Article Tells Us That Is New:

Closed-loop, automated management of anesthetic, analgesic, fluid, and ventilation parameters was superior to manual control and might influence postoperative outcomes

Background: Cognitive changes after anesthesia and surgery represent a significant public health concern. We tested the hypothesis that, in patients 60 yr or older scheduled for noncardiac surgery, automated management of anesthetic depth, cardiac blood flow, and protective lung ventilation using three independent controllers would outperform manual control of these variables. Additionally, as a result of the improved management, patients in the automated group would experience less postoperative neurocognitive impairment compared to patients having standard, manually adjusted anesthesia.

Methods: In this single-center, patient-and-evaluator-blinded, two-arm, parallel, randomized controlled, superiority study, 90 patients having noncardiac surgery under general anesthesia were randomly assigned to one of two groups. In the control group, anesthesia management was performed manually while in the closed-loop group, the titration of anesthesia, analgesia, fluids, and ventilation was performed by three independent controllers. The primary outcome was a change in a cognition score (the 30-item Montreal Cognitive Assessment) from preoperative values to those measures 1 week postsurgery. Secondary outcomes included a battery of neurocognitive tests completed at both 1 week and 3 months postsurgery as well as 30-day postsurgical outcomes.

Results: Forty-three controls and 44 closed-loop patients were assessed for the primary outcome. There was a difference in the cognition score compared to baseline in the control group versus the closed-loop group 1 week postsurgery (–1 [–2 to 0] vs. 0 [–1 to 1]; difference 1 [95% CI, 0 to 3], P = 0.033). Patients in the closed-loop group spent less time during surgery with a Bispectral Index less than 40, had less end-tidal hypocapnia, and had a lower fluid balance compared to the control group.

Conclusions: Automated anesthetic management using the combination of three controllers outperforms manual control and may have an impact on delayed neurocognitive recovery. However, given the study design, it is not possible to determine the relative contribution of each controller on the cognition score.