Hemispheric-synchronisation during anaesthesia: a double-blind randomised trial using audiotapes for intra-operative nociception control

Effect of Binaural Beats on Anxiety and Tolerance in Patients Undergoing Upper Gastrointestinal Endoscopy Without Sedation: A Randomized Controlled Trial

Objective: Binaural beats, or the perceptual auditory illusions created when simultaneously presenting two similar frequencies to each ear separately, have been used to reduce anxiety in various procedures. Unfortunately, no prior study involved preprocedure binaural music exposure among patients undergoing upper gastrointestinal endoscopy, and this study sought to investigate its effect on anxiety and tolerance among participants undergoing sedation-free upper gastrointestinal endoscopy. Methods: The prospective, controlled, randomized trial included the participation of 96 Turkish patients aged between 18 and 70 years who were scheduled for an upper gastrointestinal endoscopy, regardless of sex or illness, and were divided randomly into two different groups to undergo endoscopy, namely, the binaural beats group (n = 48) and a control group (n = 48). Patients in the binaural beat music group wore headphones, and music was given 15 mins before endoscopy; however, no particular treatment was given for either group. Anxiety levels were assessed by using the State Trait Anxiety Inventory questionnaire, in addition to changes before and after endoscopy to measure patient satisfaction based on the physician's recorded numbers of retches noted by doctors as tolerance was documented and compared among both groups. Results: The results showed that following this procedure, in the music group, state scores remained significantly lower than before them (p = 0.016), compared with the control group (p > 0.05). There was no significant difference regarding changes in diastolic or systolic heart rate or blood pressure (p > 0.05). However, the procedure tolerance and satisfaction scores were significantly higher in the music group than those without music (p < 0.05). Conclusion: For patients undergoing upper gastrointestinal endoscopy, music with binaural beats was found to significantly reduce anxiety levels and increase patient tolerance, providing an alternative option to sedative medications as a potential sedative treatment option.Clinical trials registration number: NCT06114524.

Does brain entrainment using binaural auditory beats affect pain perception in acute and chronic pain?: a systematic review

BACKGROUND

Pain is a major clinical problem across all ages with serious social and economic consequences and a great negative impact on quality of life. Brain entrainment using binaural beats is a non-pharmaceutical intervention that is claimed to have analgesic effects in acute and chronic pain. We aimed to systematically review the available randomized clinical trials on the efficacy of binaural auditory beats in reducing adults' pain perception in acute and chronic pain. A systematic search in electronic databases including Medline (via PubMed), Web of Science, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase was performed. The search was completed through Google Scholar and a manual search of the reference lists of all included studies. Randomized clinical trials with full text available in English that investigated the effect of binaural auditory beats on pain perception in acute and chronic pain in adults were included. The risk of bias was assessed by the revised Cochrane risk-of-bias (RoB 2) tool. Furthermore, The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to assess the quality of the evidence. Sixteen studies (three on chronic pain and thirteen on acute pain perception) fulfilled the eligibility criteria. Because of substantial heterogeneity of the studies, a meta-analysis was inappropriate and this review focused on the narrative interpretation of the results. The risk of bias in most studies was high and the quality of evidence was low to very low. Although the effects of binaural beats on pain perception seem to be influenced by the etiology of pain or medical procedures, our review identifies alpha or a combination of tones in the range of delta to alpha as a potential non-pharmacological intervention in reducing acute pain. However, drawing a conclusion regarding the efficacy of binaural beats for chronic pain requires more high-quality studies.

REGISTRATION

The protocol of this review was registered in PROSPERO (No. CRD42023425091).

Advances in the Cognitive Management of Chronic Pain in Children through the Use of Virtual Reality Combined with Binaural Beats: A Pilot Study

Chronic pain affects the quality of life of those affected. The need to investigate alternative and complementary methods to the pharmacological one to alleviate chronic pain is evident, so virtual reality and binaural tones have become a topic of interest in this field in recent years. This study aims to analyze the contributions of the combination of these two techniques in pediatric patients with chronic pain. For this, data on psychophysiological responses (heart rate and galvanic skin response) and pain perception are collected during and after interaction with this technology using a mixed pre- and posttest experimental methodology. The physiological data and answers in the Pediatric Pain Questionnaire (PPQ) have been collected in a sample of n = 13 healthy participants and n = 9 pediatric patients with chronic pain. The results show a significant difference between baseline and after applying virtual reality and binaural beats, md = 1.205 (t = 3.32; $p<0.05$ ). There are great effects on the perception of chronic pain if virtual reality and binaural beats are combined, even greater than with virtual reality alone, making this combination of technologies a very useful tool to be exploited for the management of chronic pain in pediatric patients with rheumatic diseases.

The efficacy of sensory neural entrainment on acute and chronic pain: A systematic review and meta-analysis

Background

Changes to the power of neural oscillations in cortical and sub-cortical structures can change pain perception. Rhythmic sensory stimulation is a non-invasive method that can increase power in specific frequencies of neural oscillations. If the stimulation frequency targets those frequencies related to pain perception, such as alpha or theta frequencies, there can be a reduction in perceived pain intensity. Thus, sensory neural entrainment may provide an alternative to pharmacological intervention for acute and chronic pain. This review aimed to identify and critically appraise the evidence on the effectiveness of sensory entrainment methods for pain perception.

Methods

We undertook a systematic search across Medline, Embase, PsycInfo, Web of Science and Scopus in November 2020 to identify studies investigating the efficacy of sensory entrainment on adults. We assessed studies for their quality using the PRISMA checklist. A random-effects model was used in a meta-analysis to measure the effect of entrainment on pain perception.

Results

Our systematic review yielded nine studies fitting the search criteria. Studies investigated the effect of visual and auditory entrainment on pain intensity rating, electrophysiological markers of pain and amount of analgesia needed during surgery. The meta-analysis suggests that alpha (8–13 Hz) sensory entrainment is effective for acute pain perception, whereas theta (4–7 Hz) entrainment is effective for chronic pain.

Conclusions

Although there is heterogeneity in the current evidence, our review highlights the potential use of sensory entrainment to affect acute and chronic pain. Further research is required regarding the timing, duration and frequency of the stimulation to determine the best application for maximum efficacy.

The Effect of Binaural Beat Audio on Operative Pain and Anxiety in Cataract Surgery under Topical Anaesthesia: A Randomized Controlled Trial

Background: The aim of this paper was to examine the analgesic and anxiolytic effects of binaural beat audio in patients undergoing cataract surgery under topical anaesthesia. Methods: This was a prospective, randomized controlled trial of 61 patients undergoing cataract surgery under topical anaesthesia. They were divided into two research conditions; the binaural beat audio group, and a sham-control group (ear phones with no music). Patients completed the State-Trait Anxiety Inventory questionnaire (STAI), and their blood pressure (BP) and heart rate (HR) were measured pre- and post-intervention. Intraoperative pain levels were ascertained using a visual analog scale (VAS) completed immediately after the surgery. Results: The binaural beat group had significantly lower pain scores (p < 0.001), HR (p < 0.001), diastolic BP (p = 0.003), mean arterial pressure (p = 0.007) and anxiety (p = 0.009) than the control group. Within the binaural beat group, subjects experienced a statistically significant reduction in HR (p = 0.004) and anxiety (p < 0.001) levels compared to baseline values, while all parameters, except anxiety, increased significantly in the control group. Conclusions: Binaural beat audio decreases operative pain and anxiety in cataract surgery under topical anaesthesia. It may have additional benefits in modulating the tachycardic response to stress.

Neurophysiological effects of various music genres on electroencephalographic (EEG) cerebral cortex activity

Background

Music has been associated with therapeutic properties for thousands of years across a vast number of diverse regions and cultures. This study expands upon our current understanding of music’s influence on human neurophysiology by investigating the effects of various music genres on cerebral cortex activity using electroencephalography (EEG).

Methods

A randomized, controlled study design was used. EEG data were recorded from 23 healthy adults, ages 19–28, while listening to a music sequence consisting of five randomized songs and two controls. The five studied music genres include: Classical, Tribal Downtempo, Psychedelic Trance (Psytrance), Goa Trance, and Subject Choice.

Results

Controls were associated with lower percentages of beta frequencies and higher percentages of alpha frequencies than the music genres. Psytrance was associated with higher percentages of theta and delta frequencies than the other music genres and controls. The lowest percentages of beta frequencies and highest percentages of alpha frequencies occurred in the occipital and parietal regions. The highest percentages of theta and delta frequencies occurred in the frontal and temporal regions. Subjects with prior music training exhibited increased percentages of delta frequencies in the frontal region. Subject gender and music preference did not have a significant influence on frequency band percentages.

Conclusions

Findings from this study support those of previous music therapy studies and provide novel insights regarding music’s influence on human neurophysiology. These findings also support the hypothesis that music may promote changes in cerebral cortex activity that have similarities to non-rapid eye movement (NREM) sleep, while the listener remains awake.

Perception of auditory stimuli during general anesthesia and its effects on patient outcomes: a systematic review and meta-analysis

Purpose

Interest in implicit memory formation and unconscious auditory stimulus perception during general anesthesia has resurfaced as perioperative music has been reported to produce beneficial effects. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating explicit and implicit memory formation during general anesthesia and its effects on postoperative patient outcomes and recovery.

Source

We performed a systematic literature search of Embase, Ovid Medline, and Cochrane Central from inception date until 15 October 2020. Eligible for inclusion were RCTs investigating intraoperative auditory stimulation in adult surgical patients under general anesthesia in which patients, healthcare staff, and outcome assessors were all blinded. We used random effects models for meta-analyses. This study adhered to the PRISMA guidelines and was registered in PROSPERO (CRD42020178087).

Principal findings

Fifty-three (4,200 patients) of 5,859 identified articles were included. There was evidence of implicit memory formation in seven out of 17 studies (41%) when assessed using perceptual priming tasks. Mixed results were observed on postoperative behavioural and motor response after intraoperative suggestions. Intraoperative music significantly reduced postoperative pain (standardized mean difference [SMD], -0.84; 95% confidence interval [CI], -1.1 to -0.57; P < 0.001; I² = 0; n = 226) and opioid requirements (SMD, -0.29; 95% CI, -0.57 to -0.015; P = 0.039; I² = 36; n = 336), while positive therapeutic suggestions did not.

Conclusion

The results of this systematic review and meta-analysis show that intraoperative auditory stimuli can be perceived and processed during clinically adequate, general anesthesia irrespective of surgical procedure severity, leading to implicit memory formation without explicit awareness. Intraoperative music can exert significant beneficial effects on postoperative pain and opioid requirements. Whether the employed intraoperative anesthesia regimen is of influence is not yet clear.

Electronic supplementary material

The online version of this article (10.1007/s12630-021-02015-0) contains supplementary material, which is available to authorized users.

The Effect of Perioperative Music on Medication Requirement and Hospital Length of Stay: A Meta-analysis

Objective:

To assess and quantify the effect of perioperative music on medication requirement, length of stay and costs in adult surgical patients.

Summary Background Data:

There is an increasing interest in nonpharmacological interventions to decrease opioid analgesics use, as they have significant adverse effects and opioid prescription rates have reached epidemic proportions. Previous studies have reported beneficial outcomes of perioperative music.

Methods:

A systematic literature search of 8 databases was performed from inception date to January 7, 2019. Randomized controlled trials investigating the effect of perioperative music on medication requirement, length of stay or costs in adult surgical patients were eligible. Meta-analysis was performed using random effect models, pooled standardized mean differences (SMD) were calculated with 95% confidence intervals (CI). This study was registered with PROSPERO (CRD42018093140) and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines.

Results:

The literature search yielded 2414 articles, 55 studies (N = 4968 patients) were included. Perioperative music significantly reduced postoperative opioid requirement (pooled SMD −0.31 [95% CI −0.45 to −0.16], P < 0.001, I² = 44.3, N = 1398). Perioperative music also significantly reduced intraoperative propofol (pooled SMD −0.72 [95% CI −1.01 to −0.43], P < 0.00001, I² = 61.1, N = 554) and midazolam requirement (pooled SMD −1.07 [95% CI −1.70 to −0.44], P < 0.001, I² = 73.1, N = 184), while achieving the same sedation level. No significant reduction in length of stay (pooled SMD −0.18 [95% CI −0.43 to 0.067], P = 0.15, I² = 56.0, N = 600) was observed.

Conclusions:

Perioperative music can reduce opioid and sedative medication requirement, potentially improving patient outcome and reducing medical costs as higher opioid dosage is associated with an increased risk of adverse events and chronic opioid abuse.

Effects of Listening to Binaural Beats on Anxiety Levels and Pain Scores in Male Patients Undergoing Cystoscopy and Ureteral Stent Removal: A Randomized Placebo-Controlled Trial

Purpose: To investigate the effects of pure binaural beats on anxiety and pain scores in male patients undergoing diagnostic cystoscopy (DC) and ureteral stent removal (USR) under local anesthesia. Materials and Methods: This was a prospective, randomized placebo-controlled study. Patients in the DC group (DCG) and USR group (USRG) were divided into three subgroups according to interventions applied; DCG-1 and USRG-1, patients listened to binaural beats; DCG-2 and USRG-2, patients listened to classical music; and DCG-3 and USRG-3, patients wore headphones, but were not exposed to audio (control group). The State-Trait Anxiety Inventory (STAI) and Visual Analog Scale (VAS) were used for measuring anxiety and pain scores, respectively. Demographic data, initial STAI, tolerance rate of interventions, terminal STAI (STAI-T), differences of STAI (delta STAI, STAI-D), and VAS scores were compared. Results: Between July 2019 and March 2020, a total of 252 and 159 eligible male patients for DCG and USRG were included, respectively. After exclusions, remaining patients were DCG-1, n = 61; DCG-2, n = 73; DCG-3, n = 75; USRG-1, n = 41; USRG-2, n = 50; and USRG-3, n = 52. The tolerance rate in binaural beat groups was significantly lower than in other groups (p < 0.05 for all). There were significant decreases in terms of STAI-T when DCG-1 and DCG-2 were compared with DCG-3 and USRG-1 and USRG-2 were compared with USRG-3 (p < 0.05 for all). There were significant decreases in STAI-D scores when DCG-1 and DCG-2 were compared with DCG-3 and when USRG-1 and USRG-2 were compared with USRG-3 (p < 0.001 for all). Binaural beat groups had significantly lower VAS scores than other groups and classical music groups had significantly lower VAS scores than control groups (p < 0.05 for all). Conclusions: Listening to pure binaural beats may be a simple and effective method to reduce anxiety levels and pain scores associated with the DC and USR procedures in males.

Reduced pain and analgesic use after acoustic binaural beats therapy in chronic pain - A double-blind randomized control cross-over trial

BACKGROUND

Binaural Beats (BB) consist of two artificial acoustic stimuli with different frequency, presented simultaneously but independently to each ear. The human brain perceives and synchronizes to this frequency difference (entrainment). Aim of this study was to test the hypothesis that brain entrainment to a lower function rhythm, with BB application, can decrease pain perception and analgesic medication use, in chronic pain patients.

METHODS

In a double blind, randomized, cross-over trial, BB at 5Hz (theta rhythm) were applied for 30 minutes, under simultaneous electroencephalogram recordings, followed by liberal, on demand use by chronic pain patients for a week, compared to sham stimulation (SS). Pain as the main outcome (numeric scale, NRS), stress (STAI) and medication usage (defined daily doses, DDD) were assessed at baseline, 30 minutes and week's end.

RESULTS

Perceived pain (NRS) was significantly reduced in BB intervention (5.6±2.3 to 3.4±2.6, p<0.001), compared to SS (5.2±2.1 to 4.8±2.3, p=0.78), during the first 30-minute phase, as well as at the week's end (to 3.9±2.5 compared to 5.5±2.6 respectively, p<0.001). The mean EEG theta power at 5Hz was significantly increased only during BB application. Stress was significantly reduced at 30 minutes in both interventions but remained reduced only in the BB group at the week's end. Analgesic medication consumption (DDD, g) during the week was significantly less in the BB intervention (3.9±3.7 vs. 4.6±4.1, p<0.05), while reporting equal to SS mean levels of pain.

CONCLUSIONS

Acoustic BB reduced pain intensity, stress and analgesic use, compared to SS, in chronic pain patients.

SIGNIFICANCE

This study provides evidence that theta rhythm binaural beats can alleviate pain intensity, both after a brief 30 minute and a longer one week on-demand intervention. The subsequent significant reduction in analgesic medication consumption in chronic pain patients' daily living could offer a valuable tool, augmenting the effect of existing pain therapies.

Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: a meta-analysis

Binaural auditory beats are a perceptual phenomenon that occurs when presenting separately to each ear two tones that slightly differ in their frequency. It has been suggested that binaural beats can influence cognition and mental states among others. The objective of this meta-analysis was to study the effect of binaural beats on memory, attention, anxiety, and analgesia. Twenty-two studies met our inclusion criteria for this meta-analysis. The results, based on 35 effect sizes, showed an overall medium, significant, consistent effect size (g = 0.45). Meta-regression results indicated that it does not seem to be necessary to mask binaural beats with white noise or pink noise in terms of effectiveness, obtaining similar effects with unmasked binaural beats. Moreover, the findings suggest that binaural-beat exposure before, and before and during the task produces superior results than exposure during the task. Time under exposure contributed significantly to the model indicating that longer periods are advisable to ensure maximum effectiveness. Our meta-analysis adds to the growing evidence that binaural-beat exposure is an effective way to affect cognition over and above reducing anxiety levels and the perception of pain without prior training, and that the direction and the magnitude of the effect depends upon the frequency used, time under exposure, and the moment in which the exposure takes place.

Does Listening to Music during Tonsillectomy Affect Sevoflurane Consumption?

OBJECTIVE

The aim of this study was to investigate the effect of listening to music on the consumption of an anesthetic agent as well as postoperative recovery and pain in children undergoing elective tonsillectomy.

MATERIALS AND METHODS

Fifty patients were randomized into those to whom music was played during surgery (group M) and a control group to whom music was not played (group C). The depth of anesthesia was provided by entropy levels of 50 ± 5 in both groups. Demographic characteristics and hemodynamic parameters were recorded perioperatively. The duration of surgery, sevoflurane consumption, eye opening time, and extubation time were also recorded. p < 0.05 was considered statistically significant.

RESULTS

Surgical pleth index values measured intraoperatively were statistically lower in group M than in group C. In the postanesthesia care unit children in the music group felt less pain than those in the control group according to the Wong-Baker Faces Pain Rating Scale (p = 0.035). The heart rates of the patients in the music group were statistically lower at 30 min intraoperatively and at the end of the procedure compared to the values of the control group (p = 0.015). The consumption of sevoflurane was lower in group M than in group C but the difference was not statistically significant. The need for additional fentanyl was significantly lower in group M than in group C.

CONCLUSION

In this study, the children exposed to music intraoperatively needed less analgesia during surgery, and reported less pain postoperatively, but there was no difference in sevoflurane requirements.

Anaesthetic interventions for prevention of awareness during surgery

BACKGROUND

General anaesthesia is usually associated with unconsciousness. 'Awareness' is when patients have postoperative recall of events or experiences during surgery. 'Wakefulness' is when patients become conscious during surgery, but have no postoperative recollection of the period of consciousness.

OBJECTIVES

To evaluate the efficacy of two types of anaesthetic interventions in reducing clinically significant awareness:- anaesthetic drug regimens; and- intraoperative anaesthetic depth monitors.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, ISSUE 4 2016); PubMed from 1950 to April 2016; MEDLINE from 1950 to April 2016; and Embase from 1980 to April 2016. We contacted experts to identify additional studies. We performed a handsearch of the citations in the review. We did not search trial registries.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of either anaesthetic regimens or anaesthetic depth monitors. We excluded volunteer studies, studies of patients prior to skin incision, intensive care unit studies, and studies that only randomized different word presentations for memory tests (not anaesthetic interventions).Anaesthetic drug regimens included studies of induction or maintenance, or both. Anaesthetic depth monitors included the Bispectral Index monitor, M-Entropy, Narcotrend monitor, cerebral function monitor, cerebral state monitor, patient state index, and lower oesophageal contractility monitor. The use of anaesthetic depth monitors allows the titration of anaesthetic drugs to maintain unconsciousness.

DATA COLLECTION AND ANALYSIS

At least two authors independently scanned abstracts, extracted data from the studies, and evaluated studies for risk of bias. We made attempts to contact all authors for additional clarification. We performed meta-analysis statistics in packages of the R language.

MAIN RESULTS

We included 160 studies with 54,109 enrolled participants; 53,713 participants started the studies and 50,034 completed the studies or data analysis (or both). We could not use 115 RCTs in meta-analytic comparisons because they had zero awareness events. We did not merge 27 of the remaining 45 studies because they had excessive clinical and methodological heterogeneity. We pooled the remaining 18 eligible RCTs in meta-analysis. There are 10 studies awaiting classification which we will process when we update the review.The meta-analyses included 18 trials with 36,034 participants. In the analysis of anaesthetic depth monitoring (either Bispectral Index or M-entropy) versus standard clinical and electronic monitoring, there were nine trials with 34,744 participants. The overall event rate was 0.5%. The effect favoured neither anaesthetic depth monitoring nor standard clinical and electronic monitoring, with little precision in the odds ratio (OR) estimate (OR 0.98, 95% confidence interval (CI) 0.59 to 1.62).In a five-study subset of Bispectral Index monitoring versus standard clinical and electronic monitoring, with 34,181 participants, 503 participants gave awareness reports to a blinded, expert panel who adjudicated or judged the outcome for each patient after reviewing the questionnaires: no awareness, possible awareness, or definite awareness. Experts judged 351 patient awareness reports to have no awareness, 87 to have possible awareness, and 65 to have definite awareness. The effect size favoured neither Bispectral Index monitoring nor standard clinical and electronic monitoring, with little precision in the OR estimate for the combination of definite and possible awareness (OR 0.96, 95% CI 0.35 to 2.65). The effect size favoured Bispectral Index monitoring for definite awareness, but with little precision in the OR estimate (OR 0.60, 95% CI 0.13 to 2.75).We performed three smaller meta-analyses of anaesthetic drugs. There were nine studies with 1290 participants. Wakefulness was reduced by ketamine and etomidate compared to thiopental. Wakefulness was more frequent than awareness. Benzodiazepines reduces awareness compared to thiopental, ketamine, and placebo., Also, higher doses of inhaled anaesthetics versus lower doses reduced the risk of awareness.We graded the quality of the evidence as low or very low in the 'Summary of findings' tables for the five comparisons.Most of the secondary outcomes in this review were not reported in the included RCTs.

AUTHORS' CONCLUSIONS

Anaesthetic depth monitors may have similar effects to standard clinical and electrical monitoring on the risk of awareness during surgery. In older studies comparing anaesthetics in a smaller portion of the patient sample, wakefulness occurred more frequently than awareness. Use of etomidate and ketamine lowered the risk of wakefulness compared to thiopental. Benzodiazepines compared to thiopental and ketamine, or higher doses of inhaled anaesthetics versus lower doses, reduced the risk of awareness.

Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics [heart rate variability (HRV)] during post-exercise relaxation. Subjects (n = 21; 18-29 years old) participated in a double-blind, placebo-controlled study during which binaural beats and placebo were administered over two randomized and counterbalanced sessions (within-subjects repeated-measures design). At the onset of each visit, subjects exercised for 20-min; post-exercise, subjects listened to either binaural beats ('wide-band' theta-frequency binaural beats) or placebo (carrier tones) for 20-min while relaxing alone in a quiet, low-light environment. Dependent variables consisted of high-frequency (HF, reflecting parasympathetic activity), low-frequency (LF, reflecting sympathetic and parasympathetic activity), and LF/HF normalized powers, as well as self-reported relaxation. As compared to the placebo visit, the binaural-beat visit resulted in greater self-reported relaxation, increased parasympathetic activation and increased sympathetic withdrawal. By the end of the 20-min relaxation period there were no observable differences in HRV between binaural-beat and placebo visits, although binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.

WITHDRAWN: Music for pain relief

2011: this review is being updated by a new author team who are preparing a new protocol. This update is due to be published in 2011.

The replacement protocol was published in September 2011 (Bradshaw DH, Brown CJ, Cepeda MS, Pace NL. Music for pain relief (Protocol). Cochrane Database of Systematic Reviews 2011, Issue 9. Art. No.: CD009284. DOI: 10.1002/14651858.CD009284).

2015: at July 2015, the PaPaS Review Group withdrew the 2011 protocol (Bradshaw 2011) as there were significant delays in preparing the full review, which did not meet the expectations of Cochrane and PaPaS editorial processes and timelines. For more information, please contact the PaPaS CRG office.

The editorial group responsible for this previously published document have withdrawn it from publication.

Sensory environment on health-related outcomes of hospital patients

BACKGROUND

Hospital environments have recently received renewed interest, with considerable investments into building and renovating healthcare estates. Understanding the effectiveness of environmental interventions is important for resource utilisation and providing quality care.

OBJECTIVES

To assess the effect of hospital environments on adult patient health-related outcomes.

SEARCH METHODS

We searched: the Cochrane Central Register of Controlled Trials (last searched January 2006); MEDLINE (1902 to December 2006); EMBASE (January 1980 to February 2006); 14 other databases covering health, psychology, and the built environment; reference lists; and organisation websites. This review is currently being updated (MEDLINE last search October 2010), see Studies awaiting classification.

SELECTION CRITERIA

Randomised and non-randomised controlled trials, controlled before-and-after studies, and interrupted times series of environmental interventions in adult hospital patients reporting health-related outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently undertook data extraction and 'Risk of bias' assessment. We contacted authors to obtain missing information. For continuous variables, we calculated a mean difference (MD) or standardized mean difference (SMD), and 95% confidence intervals (CI) for each study. For dichotomous variables, we calculated a risk ratio (RR) with 95% confidence intervals (95% CI). When appropriate, we used a random-effects model of meta-analysis. Heterogeneity was explored qualitatively and quantitatively based on risk of bias, case mix, hospital visit characteristics, and country of study.

MAIN RESULTS

Overall, 102 studies have been included in this review. Interventions explored were: 'positive distracters', to include aromas (two studies), audiovisual distractions (five studies), decoration (one study), and music (85 studies); interventions to reduce environmental stressors through physical changes, to include air quality (three studies), bedroom type (one study), flooring (two studies), furniture and furnishings (one study), lighting (one study), and temperature (one study); and multifaceted interventions (two studies). We did not find any studies meeting the inclusion criteria to evaluate: art, access to nature for example, through hospital gardens, atriums, flowers, and plants, ceilings, interventions to reduce hospital noise, patient controls, technologies, way-finding aids, or the provision of windows. Overall, it appears that music may improve patient-reported outcomes such as anxiety; however, the benefit for physiological outcomes, and medication consumption has less support. There are few studies to support or refute the implementation of physical changes, and except for air quality, the included studies demonstrated that physical changes to the hospital environment at least did no harm.

AUTHORS' CONCLUSIONS

Music may improve patient-reported outcomes in certain circumstances, so support for this relatively inexpensive intervention may be justified. For some environmental interventions, well designed research studies have yet to take place.

The anxiety- and pain-reducing effects of music interventions: a systematic review

Musical interventions have been used in health care settings to reduce patient pain, anxiety, and stress, although the exact mechanism of these therapies is not well understood. This article provides a systematic review of 42 randomized controlled trials of the effects of music interventions in perioperative settings. Music intervention had positive effects on reducing patients' anxiety and pain in approximately half of the reviewed studies. Further research into music therapy is warranted in light of the low cost of implementation and the potential ability of music to reduce perioperative patient distress.

The effects of prayer, relaxation technique during general anesthesia on recovery outcomes following cardiac surgery

During general anesthesia the possibility of subconscious perception of intraoperative events is a controversial subject. Some studies found that positive verbal suggestions, or music improved intraoperative relaxation and postoperative recovery. The aim of the current study was to evaluate the effect of prayer and relaxation technique applied while patients are under general anesthesia for open-heart surgery. A randomized, controlled, double-blind trial study included 78 patients who underwent cardiac surgery. During the surgery the patients used a headphone connected to a CD player. They were randomly divided into three groups. One group listened to prayer during the surgery, the other listened to relaxation technique and one, placebo. There was only one significant finding: the prayer group is less likely to believe that prayer would assist conventional medical treatments. Although not statistically significant, we discussed the length of stay (LOS) after surgery and the incidence of sternal wound infection.

Binaural Beat Technology in Humans: A Pilot Study To Assess Psychologic and Physiologic Effects

INTRODUCTION

Binaural beat technology (BBT) products are sold internationally as personal development and health improvement tools. Producers suggest benefit from regular listening to binaural beats including reduced stress and anxiety, and increased focus, concentration, motivation, confidence, and depth in meditation. Binaural beats are auditory brainstem responses that originate in the superior olivary nucleus as a result of different frequency auditory stimuli provided to each ear. Listeners to binaural beat "hear" a beat at a frequency equal to the difference between the frequencies of the applied tones.

OBJECTIVES

The objectives of this pilot study were to gather preliminary data on psychologic and physiologic effects of 60 days daily use of BBT for hypothesis generation and to assess compliance, feasibility, and safety for future studies.

DESIGN

Uncontrolled pilot study.

SUBJECTS

Eight healthy adults participated in the study.

INTERVENTION

Participants listened to a CD with delta (0-4 Hz) binaural beat frequencies daily for 60 days.

OUTCOME MEASURES

Psychologic and physiological data were collected before and after a 60-day intervention. PSYCHOLOGIC: Depression (Beck Depression Inventory-2), anxiety (State-Trait Anxiety Inventory), mood (Profile of Mood States), absorption (Tellegen Absorption Scale) and quality of Life (World Health Organization-Quality of Life Inventory). PHYSIOLOGICAL: Cortisol, dehydroepiandrosterone, melatonin, insulin-like growth factor-1, serotonin, dopamine, epinephrine, norepinephrine, weight, blood pressure, high sensitivity C-reactive protein.

RESULTS

There was a decrease in trait anxiety (p = 0.004), an increase in quality of life (p = 0.03), and a decrease in insulin-like growth factor-1 (p = 0.01) and dopamine (p = 0.02) observed between pre- and postintervention measurements.

CONCLUSIONS

Binaural beat technology may exhibit positive effect on self-reported psychologic measures, especially anxiety. Further research is warranted to explore the effects on anxiety using a larger, randomized and controlled trial.

Music for pain relief

BACKGROUND

The efficacy of music for the treatment of pain has not been established.

OBJECTIVES

To evaluate the effect of music on acute, chronic or cancer pain intensity, pain relief, and analgesic requirements.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE, PsycINFO, LILACS and the references in retrieved manuscripts. There was no language restriction.

SELECTION CRITERIA

We included randomized controlled trials that evaluated the effect of music on any type of pain in children or adults. We excluded trials that reported results of concurrent non-pharmacological therapies.

DATA COLLECTION AND ANALYSIS

Data was extracted by two independent review authors. We calculated the mean difference in pain intensity levels, percentage of patients with at least 50% pain relief, and opioid requirements. We converted opioid consumption to morphine equivalents. To explore heterogeneity, studies that evaluated adults, children, acute, chronic, malignant, labor, procedural, or experimental pain were evaluated separately, as well as those studies in which patients chose the type of music.

MAIN RESULTS

Fifty-one studies involving 1867 subjects exposed to music and 1796 controls met inclusion criteria. In the 31 studies evaluating mean pain intensity there was a considerable variation in the effect of music, indicating statistical heterogeneity ( I(2) = 85.3%). After grouping the studies according to the pain model, this heterogeneity remained, with the exception of the studies that evaluated acute postoperative pain. In this last group, patients exposed to music had pain intensity that was 0.5 units lower on a zero to ten scale than unexposed subjects (95% CI: -0.9 to -0.2). Studies that permitted patients to select the music did not reveal a benefit from music; the decline in pain intensity was 0.2 units, 95% CI (-0.7 to 0.2). Four studies reported the proportion of subjects with at least 50% pain relief; subjects exposed to music had a 70% higher likelihood of having pain relief than unexposed subjects (95% CI: 1.21 to 2.37). NNT = 5 (95% CI: 4 to 13). Three studies evaluated opioid requirements two hours after surgery: subjects exposed to music required 1.0 mg (18.4%) less morphine (95% CI: -2.0 to -0.2) than unexposed subjects. Five studies assessed requirements 24 hours after surgery: the music group required 5.7 mg (15.4%) less morphine than the unexposed group (95% CI: -8.8 to -2.6). Five studies evaluated requirements during painful procedures: the difference in requirements showed a trend towards favoring the music group (-0.7 mg, 95% CI: -1.8 to 0.4).

AUTHORS' CONCLUSIONS

Listening to music reduces pain intensity levels and opioid requirements, but the magnitude of these benefits is small and, therefore, its clinical importance unclear.

The Effect of Hemispheric Synchronization on Intraoperative Analgesia

In this double-blinded randomized study, we sought to confirm that patients undergoing general anesthesia who were exposed to a hemispheric synchronization (Hemi-Sync) musical recording during surgery had a smaller analgesia requirement, as was suggested in a previous study. Bispectral index monitoring was used to adjust depth of hypnosis, and hemodynamic variables were used to determine analgesia administration. Consented patients underwent either laparoscopic bariatric or one-level lumbar disk surgery. After endotracheal intubation and application of headphones, baseline heart rate and arterial blood pressure were established. Isoflurane was titrated to maintain sedation on the basis of a target bispectral index range of 40-60, and 25-microg increments of fentanyl were administered in response to increases in heart rate and systolic arterial blood pressure. Bariatric patients who listened to Hemi-Sync required one-third less fentanyl than the control group (mean [SD]: 0.015 [0.01] vs 0.024 microg.kg(-1).min(-1) [0.01]) (P = 0.009). It is interesting to note that lumbar patients in the experimental and control groups required similar amounts of fentanyl (0.012 [0.01] vs 0.015 microg.kg(-1).min(-1) [0.01]). End-tidal isoflurane concentration was similar for Hemi-Sync and blank-tape patients (bariatric, 0.74% (0.14) vs 0.77% (0.21); lumbar, 0.36% [0.16] vs 0.39% [0.12]). The bariatric patients in this study demonstrated that Hemi-Sync may be an innovative intraoperative supplement to analgesia.

IMPLICATIONS

The purpose of this study was to determine the decrease in analgesia requirement for patients listening to hemispheric synchronization (musical tones) while under general anesthesia. We demonstrated that bariatric patients who listened to hemispheric synchronization had a smaller analgesia requirement than those who listened to a blank tape.

The Effect of Music on the Neurohormonal Stress Response to Surgery Under General Anesthesia

Several pharmacological interventions reduce perioperative stress hormone release during surgery under general anesthesia. Listening to music and therapeutic suggestions were also studied, but mostly in awake patients, and these have a positive effect on postoperative recovery and the need for analgesia. In this study, we evaluated the effect of listening to music under general anesthesia on the neurohormonal response to surgical stress as measured by epinephrine, norepinephrine, cortisol, and adrenocorticotropic hormone (ACTH) blood levels. Thirty female patients scheduled for abdominal gynecological procedures were enrolled and randomly divided into two groups: group NM (no music) and group M (music). In group M, music was played from after the induction of anesthesia until the end of surgery. In the NM group, the patients wore the headphones but no music was played. We established three sample times for hormonal dosage during the procedure and one in the recovery room. Hemodynamic data were recorded at all times, and postoperative consumption of morphine in the first 24 h was noted. There was no group difference at any sample time or in the postoperative period in terms of mean arterial blood pressure, heart rate, isoflurane end-tidal concentration, time of the day at which the surgery was performed, bispectral index (BIS) value, doses of fentanyl, or consumption of postoperative morphine. There was no difference between the two groups with regard to plasmatic levels of norepinephrine, epinephrine, cortisol, or ACTH at any sample time, although the blood level of these hormones significantly increased in each group with surgical stimulation. In conclusion, we could not demonstrate a significant effect of intraoperative music on surgical stress when used under general anesthesia.

IMPLICATIONS

Listening to music under general anesthesia did not reduce perioperative stress hormone release or opioid consumption in patients undergoing gynecological surgery.

Hemispheric synchronized sounds and intraoperative anesthetic requirements

Hemispheric synchronization is currently promoted as a treatment for preoperative anxiety and for reduction of intraoperative anesthetic and analgesic consumption. We designed this study to examine the effect of Hemisync sounds on anesthetic hypnotic depth. After obtaining informed consent, we randomized subjects undergoing general anesthesia and outpatient surgery into two groups: the treatment group received Hemisync sounds (n = 31), and the control group received a blank cassette tape (n = 29). Both groups received the intervention in the preoperative area and during the surgical procedure. Subjects underwent a propofol-based anesthetic regimen, and propofol doses required for the induction and maintenance of anesthesia were recorded. A bispectral index monitor was used to ensure that the hypnotic component of the anesthetic state was the same in all patients. We found no differences in the amount of propofol used during the induction of anesthesia (2.49 +/- 0.59 mg/kg versus 2.60 +/- 0.59 mg/kg; P = 0.48) or the maintenance of anesthesia (0.141 +/- 0.02 mg x kg(-1) x min(-1) versus 0.146 +/- 0.04 mg x kg(-1) x min(-1); P = 0.62) between the Hemisync and control groups. We also found no differences between the Hemisync group and the control group for participants with high state anxiety (P = not significant). We conclude that Hemisync sounds do not reduce the hypnotic component of the anesthetic state of patients undergoing general anesthesia and surgery.

Improved recovery after music and therapeutic suggestions during general anaesthesia: a double-blind randomised controlled trial

PURPOSE

This study was designed to determine whether music or music in combination with therapeutic suggestions in the intra-operative period under general anaesthesia could improve the recovery of hysterectomy patients.

METHODS

In a double-blind randomised clinical investigation, 90 patients who underwent hysterectomy under general anaesthesia were intra-operatively exposed to music, music in combination with therapeutic suggestion or operation room sounds. The anaesthesia was standardised. Postoperative analgesia was provided by a patient-controlled analgesia (PCA). The pain scores were recorded by means of a visual analogue scale. Nausea, emesis, bowel function, fatigue, well-being and duration of hospital stay were studied as outcome variables.

RESULTS

On the day of surgery, patients exposed to music in combination with therapeutic suggestions required less rescue analgesic compared with the controls. Patients in the music group experienced more effective analgesia the first day after surgery and could be mobilised earlier after the operation. At discharge from the hospital patients in the music and music combined with therapeutic suggestion group were less fatigued compared to the controls. No differences were noted in nausea, emesis, bowel function, well-being or length of hospital stay between the groups.

CONCLUSION

This double-blind study has demonstrated that intra-operative music and music in combination with therapeutic suggestions may have some beneficial effects on postoperative recovery after hysterectomy. Further controlled studies are necessary to confirm our results.