EEG during Anesthesia Does Not Reduce Delirium in Older Adults after Cardiac Surgery

Deschamps A, Abdallah AB, Jacobson E, et al. Electroencephalography-Guided Anesthesia and Delirium in Older Adults After Cardiac Surgery: The ENGAGES-Canada Randomized Clinical Trial. JAMA 332, 112-123 (2024).

Berger M, Neuman MD. Anesthesia Dose and Delirium—A Picture Coming Into Focus. JAMA. 332, 107-108 (2024).

Available evidence suggests that electroencephalography-guided (EEG) wave suppression during general anesthesia is related to anesthetic agent dosage and these EEG changes are associated with an increased risk for postoperative delirium.

This article reported data from a randomized, prospective trial that compared EEG-guided anesthesia (n = 567) with usual care (n = 573) in patients 60 years of age and older who underwent cardiac surgery procedures. The primary outcome of interest was a diagnosis of delirium within the first 5 days after the procedure, and the secondary outcomes included ICU and hospital length of stay, complications, mortality and intraoperative awareness.

Delirium was diagnosed in 18.15% of the EEG-guided anesthesia group and in 18.1% of the usual care group. Lengths of stay were similar in the two groups; no patients reported intraoperative awareness. Complication and mortality rates were similar in the two groups.

The authors concluded that EEG-guided anesthesia did not reduce the risk for postoperative delirium following cardiac surgery procedures.

In the accompanying editorial, Berger and Neuman noted that other published data have reported reduced risk of delirium in patients receiving EEG-guided anesthesia. Of note was the fact that studies showing reductions in delirium included younger patients with fewer comorbid conditions. They emphasized that future research could identify patients at higher risk for delirium who might benefit from EEG-guided anesthesia.