Binaural beat stimulation as a tool to reduce preoperative anxiety in patients undergoing elective surgery and general anesthesia - results from a randomized controlled trial.

Introduction: Pronounced anxiety is increasing in society and is common in patients awaiting surgery. It's associated with increased anesthetic requirements, increased postsurgical pain, and also adverse postoperative outcomes. Binaural beats have been proposed as a non-pharmacological intervention to reduce anxiety in medical settings.

Age-dependent changes in the power spectrum conflate composite scores to assess brain frailty.

Objective: Evaluating age-related dependencies in the electroencephalogram (EEG) during induction of general anesthesia and their impact on composite scores used to assess frailty.

Methods: A composite score was derived from spectral edge frequency, total power, alpha power, and the effect-site concentration (Ce) of propofol. All these parameters are influenced by age, brain health, and dosage and speed of drug administration.

Spectral Differences of Anesthetic Agents: Addressing Fundamental Problems With New Methods.

Background: Processed electroencephalography parameters are used to guide anesthesia to adequate levels for surgical procedures. Despite known spectral differences between anesthetics, studies often assume similar anesthetic states when titrating to the same target values, presupposing a reductive one-size-fits-all approach for all anesthetic agents. We hypothesize this may introduce bias and aim to characterize the differences using conventional and new approaches.

EEG features associated with Alzheimer's disease and Frontotemporal dementia are not reflected by processed indices used in anesthesia monitoring.

Patients with dementia face increased risks after general anesthesia. Improved perioperative electroencephalogram (EEG) monitoring techniques could aid in identifying vulnerable patients. However, current technology relies on processed indices to measure "depth-of-anesthesia".

Evaluation of different intramuscular injectable anesthetic combinations in rabbits: Impact on anesthetic depth, physiological parameters, and EEG recordings.

Rabbits have a high anesthesia-related mortality rate because of their small size, high metabolic rate and challenging airway management. This study aimed to investigate different combinations of intramuscularly administered anesthetics in New Zealand White rabbits, focusing on their effects on anesthetic depth, physiological parameters, and electroencephalogram (EEG) recordings. Defined doses ketamine (K), esketamine (SK), medetomidine (M), dexmedetomidine (D), midazolam (Mi), and butorphanol (B) were investigated and compared in five different combinations: KM (25/0.

Aperiodic component of the electroencephalogram power spectrum reflects the hypnotic level of anaesthesia.

Background: Aperiodic (nonoscillatory) electroencephalogram (EEG) activity can be characterised by its power spectral density, which decays according to an inverse power law. Previous studies reported a shift in the spectral exponent α from consciousness to unconsciousness. We investigated the impact of aperiodic EEG activity on parameters used for anaesthesia monitoring to test the hypothesis that aperiodic EEG activity carries information about the hypnotic component of general anaesthesia.

Changes in Intra- and Cross-hemispheric Directed Functional Connectivity in the Electroencephalographic Signals during Propofol-induced Loss of Consciousness.

Background: Numerous, sometimes conflicting, changes in brain functional connectivity have been associated with the transition from wakefulness to unresponsiveness at induction of general anesthesia. However, relatively few studies have looked at the detailed time evolution of the transition, for different electroencephalogram (EEG) frequency bands, and in the clinical scenario of surgical patients undergoing general anesthesia.

Methods: The authors investigated the changes in the frontal and frontoparietal directed and undirected functional connectivity to multichannel EEG data recorded from 29 adult male surgical patients undergoing propofol-induced loss of consciousness during induction of anesthesia.

Permutation Entropy Does Not Track the Electroencephalogram-Related Manifestations of Paradoxical Excitation During Propofol-Induced Loss of Responsiveness: Results From a Prospective Observational Cohort Study.

Background: During the anesthetic-induced loss of responsiveness (LOR), a "paradoxical excitation" with activation of β-frequencies in the electroencephalogram (EEG) can be observed. Thus, spectral parameters-as widely used in commercial anesthesia monitoring devices-may mistakenly indicate that patients are awake when they are actually losing responsiveness. Nonlinear time-domain parameters such as permutation entropy (PeEn) may analyze additional EEG information and appropriately reflect the change in cognitive state during the transition.

Development of Postanesthesia Care Unit Delirium Is Associated with Differences in Aperiodic and Periodic Alpha Parameters of the Electroencephalogram during Emergence from General Anesthesia: Results from a Prospective Observational Cohort Study.

Background: Intraoperative alpha-band power in frontal electrodes may provide helpful information about the balance of hypnosis and analgesia and has been associated with reduced occurrence of delirium in the postanesthesia care unit. Recent studies suggest that narrow-band power computations from neural power spectra can benefit from separating periodic and aperiodic components of the electroencephalogram. This study investigates whether such techniques are more useful in separating patients with and without delirium in the postanesthesia care unit at the group level as opposed to conventional power spectra.

Preoperative characterization of baseline EEG recordings for risk stratification of post-anesthesia care unit delirium.

Study Objective: Delirium in the post-anesthesia care unit (PACU-D) presents a serious condition with a high medical and socioeconomic impact. In particular, PACU-D is among common postoperative complications of elderly patients. As PACU-D may be associated with postoperative delirium, early detection of at-risk patients and strategies to prevent PACU-D are important.