Binaural Beat Stimulation to Improve Patient Outcome After Surgery and Anesthesia

Study Overview
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Brief Summary
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We plan to evaluate the potential of binaural beat stimulation as a cost-effective tool to improve perioperative patient outcome. Preoperative anxiety and postoperative neurocognitive disorders are two major issues patients have to deal with in the perioperative period. In this context, preoperative stress and anxiety are independent risk factors for postoperative neurocognitive disorders. The primary goal of our proposed study therefore is to reduce preoperative anxiety by stimulating patients with binaural beats. As binaural beats might also entrain brainwaves, the secondary goal of the study is to investigate whether binaural beats can induce alpha oscillatory activity during emergence from anesthesia. This type of oscillation has been demonstrated to be protective for postoperative neurocognitive disorders and might therefore complement the effects of preoperative anxiety reduction.

Official Title
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Binaural Beat Stimulation as a Cost-effective Tool to Reduce Preoperative Anxiety and Improve Postoperative Outcome After General Anesthesia

Conditions
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Preoperative Anxiety, Perioperative Complication

Intervention / Treatment
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* Other: Binaural Beat Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Fluent in German (Munich) or Portuguese (Porto) Scheduled for elective minor or intermediate risk procedure Exclusion Criteria: ASA status 4 History of drug abuse Pre-existing neurocognitive or psychiatric disorders Auditory Impairments, vision diseases or other diagnosed cognitive impairments

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Control Group, no Intervention received | |
| Experimental: Preop Stimulation<br>Binaural Beat Stimulation preoperatively | Other: Binaural Beat Stimulation<br>* During binaural beats stimulation both ears receive a tone which varies slightly in its frequency. If the left ear is stimulated with a sinusoidal wave of 98 Hz and the right ear with a sinusoidal wave of 108 Hz, the brain will perceive this stimulation as a single tone at the mean frequency of 103 Hz. The amplitude of the perceived tone will fluctuate with a frequency that is equal to the difference of the two initial tones, i.e., 10 Hz<br>|
| Experimental: Postop Stimulation<br>Binaural Beat Stimulation postoperatively | Other: Binaural Beat Stimulation<br>* During binaural beats stimulation both ears receive a tone which varies slightly in its frequency. If the left ear is stimulated with a sinusoidal wave of 98 Hz and the right ear with a sinusoidal wave of 108 Hz, the brain will perceive this stimulation as a single tone at the mean frequency of 103 Hz. The amplitude of the perceived tone will fluctuate with a frequency that is equal to the difference of the two initial tones, i.e., 10 Hz<br>|
| Experimental: Pre- & Postop Stimulation<br>Binaural Beat Stimulation pre- and postoperatively | Other: Binaural Beat Stimulation<br>* During binaural beats stimulation both ears receive a tone which varies slightly in its frequency. If the left ear is stimulated with a sinusoidal wave of 98 Hz and the right ear with a sinusoidal wave of 108 Hz, the brain will perceive this stimulation as a single tone at the mean frequency of 103 Hz. The amplitude of the perceived tone will fluctuate with a frequency that is equal to the difference of the two initial tones, i.e., 10 Hz<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction of preoperative anxiety | Binaural beat stimulation before surgery can reduce preoperative anxiety | Assessments will take place one day before surgery as well as before administration of the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Increase of EEG alpha-band power during anesthesia emergence | Binaural beat stimulation during anesthesia emergence can increase or stabilize EEG alpha-band power. | Analysis will include the last 20 minutes of surgical procedure until patients are responsive again | 
| Lower incidence of perioperative neurocognitive disorders | 2. Reduced preoperative anxiety and/or increased or stabilized alpha oscillations during anesthesia emergence are correlated with a lower incidence of perioperative neurocognitive disorders. | Incidence of perioperative neurocognitive disorders will be assessed during the patients stay in the PACU as well as one day post surgery |