Related Experiment Video
Updated: Aug 24, 2026

Recording Brain Electromagnetic Activity During the Administration of the Gaseous Anesthetic Agents Xenon and Nitrous Oxide in Healthy Volunteers
Published on: January 13, 2018
[Increase in bispectral index induced by antihyperalgesic dose of ketamine]
K Chaaben1, E Marret, L Lamonerie
1Département d'anesthésie-réanimation, 4, rue de la Chine, 75970 Paris cedex 020, France.
Abstract:
We report two cases of sudden increase in Bispectral Index (BIS) after the injection of low-dose ketamine for the prevention of postoperative hyperalgesia. The two patients were anaesthetised with a continuous infusion of remifentanil associated with propofol for one and isoflurane for the other. Changes in BIS occurred while the two patients were in a stable phase of surgery (beginning of parietal closure and suture of an anastomosis) and had a stable target concentration of anaesthetic agents. No others signs of awakening were observed. The BIS value returned progressively to 40-50 despite no increase in target concentration. None of the patients complained of intra-operative recall.
Related Concept Videos
Parenteral Anesthetics: Overview
Stages of General Anesthesia
Analgesia and Pain Management
Inhalational Anesthetics: Overview
