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The influence of white noise on sleep in subjects exposed to ICU noise
Abstract
There is disagreement in the literature about the importance of sleep disruption from intensive care unit (ICU) environmental noise. Previous reports have assumed that sleep disruption is produced by high-peak noise. This study aimed to determine whether peak noise or the change in noise level from baseline is more important in inducing sleep disruption. We hypothesized that white noise added to the environment would reduce arousals by reducing the magnitude of changing noise levels.
Four subjects underwent polysomnography under three conditions: (1) baseline, (2) exposure to recorded ICU noise and (3) exposure to ICU noise and mixed-frequency white noise, while one additional subject completed the first two conditions. Baseline and peak noise levels were recorded for each arousal from sleep.
A total of 1178 arousals were recorded during these studies. Compared to the baseline night (13.3+/-1.8 arousals/h) the arousal index increased during the noise (48.4+/-7.6) but not the white noise/ICU noise night (15.7+/-4.5) (P<0.004). The change in sound from baseline to peak, rather than the peak sound level, determined whether an arousal occurred and was the same for the ICU noise and white noise/ICU noise condition (17.7+/-0.4 versus 17.5+/-0.3 DB, P=0.65).
Peak noise was not the main determinant of sleep disruption from ICU noise. Mixed frequency white noise increases arousal thresholds in normal individuals exposed to recorded ICU noise by reducing the difference between background noise and peak noise.
... The results of sleep and WN studies, which account for 15.2% of the studies, are summarized in Table 1. White noise (50 to 75 dB) has demonstrated positive and improving effects on the sleep and wake cycle of participants in all the studies in which it was used as an intervention (17)(18)(19)(20)(21).As a result of these studies and comparisons between target and control groups, WN has proven to be effective in reducing the number of infants awakening during nighttime sleep, improving their sleep quality, and helping them sleep better. Children with ASD also reported fewer sleep onset delays and fewer night wakeups following this intervention (20). ...
... Meanwhile, a study on healthy adults found that when WN is used, the difference between background noise and peak noise is decreased, increasing the arousal threshold in people to the noise. As a result, it leads to complete sleep and less arousal during sleep (21). In short, WN is a promising intervention for improving sleep that can be investigated further. ...
... By involving long-term memory structures, such as the hippocampus, and by enhancing learning capacity, WN simplifies and im-proves the learning process for new vocabulary (25,26).According to polysomnographic studies, adding mixed-frequency WN to the ambient noise led to a significant reduction in sleepinduced arousal and sleep disturbance since the difference between background and peak sounds was significantly reduced. Thus, WN promotes more profound and more restful sleep (18)(19)(20)(21). ...
Background:
White noise (WN), because of its unique behavior and characteristics, has different applications in different sciences. Nevertheless, the results of studies and reviews of the literature on occupational safety and health found that this type of noise is often used as a noise source to assess the effects of hearing and its physical characteristics. Its possible applications in this area have not received as much attention. The present review study aimed to answer the question, "Can WN be used as a means of promoting occupational safety and health at the workplace?".
Methods:
In this review, we reviewed the articles published in reputable databases from 1990 to 2020. Our study included 33 articles from 120 that were searched in full text and followed the inclusion and exclusion criteria.
Results:
Various applications were examined, including noise masking, white noise therapy, cognitive functions, and sleep. WN can enhance the work environment and meet occupational safety and health objectives based on the study's results. The results of this study will provide a basis for continuing research into the use of WN in the workplace as an engineering and management control method.
Conclusion:
WN is being used in various fields that may hold promise for its application in occupational health sciences and maintaining the well-being of workplace workers.
... For the nighttime hours, we also measured the frequency of noise spikes >80 dB, sound level changes (SLCs, the difference between two consecutive sound measurements) >17.5 dB, and light spikes >150 lux -all of which are associated with night wakings. 12,14,19 Data were analyzed using RStudio. ...
... Nighttime noise levels always exceeded WHO recommendations for sleep, 15 with patients exposed to multiple noise spikes associated with night wakings. 12,14,19 While light levels were frequently dim enough to be conducive to sleep at night, patients were rarely exposed to light bright enough to preserve a healthy circadian rhythm during the day. Furthermore, the afternoon timing of the brightest daytime light exposure was also not ideal for maintaining circadian entrainment. ...
... 5 Humans can become accustomed to a persistently noisy environment so long as it is constant -variability may drive night wakings. 12,14,19 By two different metrics, children in our study were exposed to exceedingly disruptive noise: 3.4 noise spikes >80 dB (roughly equivalent to a gas-powered lawnmower 20 ) and 5.6 SLCs >17.5 dB per night. It may be important to focus intervention efforts on minimizing brief, but problematic, bursts of sound. ...
Noise and light levels during hospitalizations can disrupt sleep and circadian health, resulting in worse health outcomes. This study describes patterns of noise and light in an inpatient room of children undergoing stem cell transplants. Objective meters tracked noise and light levels every minute for 6 months. Median overnight sound was 55dB (equivalent to conversational speech), which exceeded recommendations. There were 3.4 loud noises (>80dB) per night on average. Children spent 62% of the 24-hour cycle in non-optimal lighting, with daytime light dimmer than recommended 98% of the time. These data suggest improvements for hospital environment in pediatric cancer patients.
... Quality sleep is a commonly used term, but it has not yet been well defined. Akerstedt et al. commented that "in fact, there seems to be little systematic knowledge about what constitutes subjectively good sleep and how to measure it" [72], and Buysse et al. define sleep quality as "complex phenomena that are difficult to define and measure objectively" [73]. According to a study conducted by Harvey et al., which investigated the subjective meaning of people's perceptions of sleep quality, the most common item that people with insomnia and the healthy general public responded to as being related to quality sleep was "Motivation to get up or sleep in the morning", "Tiredness on waking and throughout the day", "Sleep onset latency", and "Awakenings in the night" [74]. ...
... In sound masking, the arousal caused by distracting external background noise can be minimized by continuously reproducing pure colored noise at a relatively greater intensity. A representative study of this evidence was conducted by Stanchina et al. [73]. In this study, sound sources recorded in the intensive care unit, including patient care activities, nurse-patient interactions, periodic alarms from mechanical ventilators, infusion pumps, and mixed background noise, were present during polysomnography. ...
... In the studies by Williamson and Umbas, natural sounds such as waterfall or rain were used as sound sources, which can mask surrounding noise similarly to white noise [44,46]. In Williamson, since the experiment focused on night sleep of patients in an intensive care unit, it is judged that sound masking caused by natural sounds helped to induce sleep under conditions similar to that found in the study by Stanchina et al. [44,73]. Since the study of Umbas et al. was conducted in the dormitory, it is thought that masking by sounds of nature helped to induce sleep in an environment containing various living noises [46]. ...
The increased demand for well-being has fueled interest in sleep. Research in technology for monitoring sleep ranges from sleep efficiency and sleep stage analysis to sleep disorder detection, centering on wearable devices such as fitness bands, and some techniques have been commercialized and are available to consumers. Recently, as interest in digital therapeutics has increased, the field of sleep engineering demands a technology that helps people obtain quality sleep that goes beyond the level of monitoring. In particular, interest in sleep aids for people with or without insomnia but who cannot fall asleep easily at night is increasing. In this review, we discuss experiments that have tested the sleep-inducing effects of various auditory stimuli currently used for sleep-inducing purposes. The auditory stimulations were divided into (1) colored noises such as white noise and pink noise, (2) autonomous sensory meridian response sounds such as natural sounds such as rain and firewood burning, sounds of whispers, or rubbing various objects with a brush, and (3) classical music or a preferred type of music. For now, the current clinical method of receiving drugs or cognitive behavioral therapy to induce sleep is expected to dominate. However, it is anticipated that devices or applications with proven ability to induce sleep clinically will begin to appear outside the hospital environment in everyday life.
... When WN is given, a more number of neonates fell asleep within five minutes than is not given [10]. For improving sleep experience, WN is recommended to use in intensive care unit and coronary care [11], [12]. Natural sounds are popular to induce sleep on the internet. ...
... We set that the window is 512 and the number of overlap samples is 256. We used the four frequency bands: delta (0.5-4 Hz), theta (4-8 Hz), alpha (8)(9)(10)(11)(12)(13)(14), and beta (14-40 Hz) bands. Therefore, we got f by T matrix from each 10 min occipital EEG during auditory stimulation (f : 4 and T : 586). ...
... However, we could not check it since they did not perform PSQI. WN was recommended to use in intensive care unit and coronary care because WN has a masking effect to prevent other noise [11], [12]. In our laboratory environment, there was no other noise, and our results did not come from noise masking effects. ...
Sleep has a significant role to maintain our health. However, people have struggled with sleep induction because of noise, emotion, and complicated thoughts. We hypothesized that there was more effective auditory stimulation to induce sleep based on their mental states. We investigated five auditory stimulation: sham, repetitive beep, binaural beat, white noise, and rainy sounds. The Pittsburgh sleep quality index was performed to divide subjects into good and poor sleep groups. To verify the subject's mental states between initiation of sessions, a psychomotor vigilance task and Stanford sleepiness scale (SSS) were performed before auditory stimulation. After auditory stimulation, we asked subjects to report their sleep experience during auditory stimulation. We also calculated alpha dominant duration that was the period that represents the wake period during stimulation. We showed that there were no differences in reaction time and SSS between sessions. It indicated sleep experience is not related to the timeline. The good sleep group fell asleep more frequently than the poor sleep group when they hear white noise and rainy sounds. Moreover, when subjects failed to fall asleep during sham, most subjects fell asleep during rainy sound (Cohen's kappa: -0.588). These results help people to select suitable auditory stimulation to induce sleep based on their mental states.
... 9 The mechanism of white noise can improve sleep quality is still unclear. 10 Some research abroad shows that listening to white noise can improve sleep quality continuously by increasing the acoustic threshold to the maximum so that the surrounding noise is less able to stimulate the brain during sleep. Some research also shows that white noise affects the electrical activity of the brain and improves sleep quality by reducing the latency of sleep onset and triggering deeper sleep so that it can improve one's sleep architecture. ...
... Some research also shows that white noise affects the electrical activity of the brain and improves sleep quality by reducing the latency of sleep onset and triggering deeper sleep so that it can improve one's sleep architecture. [10][11][12] Based on the description above, we are interested in researching the effect of white noise on the sleep quality of individuals who are the subject of our study. ...
... Interventions given to improve participants' sleep quality are white noise stimulation that is played every night for 60 min as a lullaby, where white noise can affect the electrical activity of the brain and improve sleep quality by reducing the latency of sleep onset and triggering deeper sleep to improve sleep architecture of a person. [10][11][12] After completing the intervention for the participants for 30 days, based on the results of the post-test, the mean PSQI score decreased to 6.50 ± 3.00. Some participants said there was an increase in sleep quality, improved sleep latency, improved sleep efficiency, reduced frequency of sleep disturbance at night, no use of sleeping pills, and improved dysfunction in daytime activities. ...
Objective
To know the effect of white noise on the sleep quality at high senior students in Putri Rajawali Makassar.
Aim
This study aimed to evaluate the effect of white noise on the sleep quality of high school students at Unit B of Rajawali Girls Dormitory Makassar.
Methods
This was an experimental study involving twelve subjects, ages 16–18, with a total sampling method. The JBL T5 speaker was placed in the subject's room to generate white noise for 30 days. The white noise was listened continuously from 10 pm to 5 am, and sleep quality was measured subjectively with the Pittsburgh Sleep Quality Index (PSQI) before and after the intervention. Then the data were analyzed by paired t-test.
Results
The mean of PSQI score before the intervention was 8.50 ± 2.5 and significantly decrease into 6.50 ± 3.00 after the intervention (p-value 0.019).
Conclusion
White noise decreased the score of PSQI, which interpreted as better sleep quality.
... Descriptive studies have defined and expanded our understanding of the relationship between environmental problems and serious sleep disturbances in the ICU [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39]. Consequently, several studies have evaluated interventions targeting sleep optimization in the ICU, including non-pharmacologic and pharmacologic interventions [21,30,[40][41][42][43][44][45][46][47][48][49][50][51]. As for pharmacological therapy, this should be for short periods, with continuous re-evaluation of the need due to adverse effects. ...
... In neonates and infants, auditory masking has been useful in promoting sleep [25,32]. In normal individuals, the addition of mixed-frequency white noise substantially reduces sleep arousals, and although the mean basal sound level increases with the addition of white noise, sleep is more consolidated and arousals occur much less frequently [31,46]. In the ICU, patients exposed to white noise improve and maintain qualitatively assessed sleep [45] and it is more effective in improving sleep than other noise reduction strategies, such as earplugs [25]. ...
Introduction:
In critically ill patients, sleep and circadian rhythms are greatly altered. These disturbances have been associated with adverse consequences, including increased mortality. Factors associated with the ICU environment, such as exposure to inadequate light and noise levels during the day and night or inflexible schedules of daily care activities, have been described as playing an essential role in sleep disturbances. The main objective of this study is to evaluate the impact of the use of a multifaceted environmental control intervention in the ICU on the quantity and quality of sleep, delirium, and post-intensive care neuropsychological impairment in critically ill patients.
Methods:
This is a prospective, parallel-group, randomized trial in 56 critically ill patients once they are starting to recover from their acute illness. Patients will be randomized to receive a multifaceted intervention of environmental control in the ICU (dynamic light therapy, auditory masking, and rationalization of ICU nocturnal patient care activities) or standard care. The protocol will be applied from enrollment until ICU discharge. Baseline parameters, light and noise levels, polysomnography and actigraphy, daily oscillation of plasma concentrations of Melatonin and Cortisol, and questionnaires for the qualitative evaluation of sleep, will be assessed during the study. In addition, all patients will undergo standardized follow-up before hospital discharge and at 6 months to evaluate neuropsychological impairment.
Discussion:
This study is the first randomized clinical trial in critically ill patients to evaluate the effect of a multicomponent, non-pharmacological environmental control intervention on sleep improvement in ICU patients. The results will provide data about the potential synergistic effects of a combined multi-component environmental intervention in ICU on outcomes in the ICU and long term, and the mechanism of action.
Trial registration:
ClinicalTrials.gov, NCT. Registered on January 10, 2023. Last updated on 24 Jan 2023.
... [8] In some of the experiments, white noise was played two hours after the experimenters were in bed; while in other experiments that are in the hospitals, the white noise was stopped after the experimenters fell into deep sleep based on observations of brain waves. [9] The whole experiment would last for one month or more. The experiments in a small number of selected papers did not set a control group, but the data of various sleep factors in different periods in the experimental group were clearly analyzed, and the experimental environment was relatively stable. ...
... Whether for patients admitted to the ICU for physical illness or admitted for observation for mental illness, white noise significantly improved their sleep quality. [9] The study was limited by age coverage and a lack of long-term monitoring of side effects. Except for those involving infants and young children, most of the experiments were not clearly divided by age, which resulted in a lack of research comprehensiveness. ...
... Hastalarda, okyanus sesinin (beyaz ses -white noise) ses maskesi olarak kullanıldığı gecelerde derin uyku süreleri ile buna bağlı olarak uyku kalitesinin arttığı ve ani uyanma durumlarının azalttığı belirtilmiştir. Beyaz sesin ses maskesi olarak uygulandığı çalışmalarda uykunun %42,7 iyileştiği bildirilmiştir [90,91]. Hastane cihazlarından ortama yayılan seslerin kontrolü için akustik köpüklerin kullanıldığı bir çalışmada ise ses şiddetinin 3,3 dB(A) azaldığı gözlemlenmiştir [92]. ...
... Ülkemizde belediyelerin ve üniversitelerin araştırmaları sonucu belirlenen gürültü haritaları, eylem planlarının sınır değerler üzerindeki gürültü seviyesine maruz kalan kişilerin etkilenmemesi durumuna ilişkin önlemleri değerlendirmektedir. Ülkemizde yapılan çalışmalar trafik nedenli gürültü problemlerine ilişkin önlemler sunmuşlardır [62,63,70,[85][86][87][88][89][90][91][92][93][94][95][96][97][98]. Bir çalışmada, kara yolu trafiği için trafik yönetiminin (hız sınırları, trafik yoğunluğu, kompozisyonu gibi etmenlerin değerlendirilmesi) ve ses emici yol üst yapı tiplerinin (gözenekli asfalt kullanımı) kullanılması önerilmiştir [70]. ...
Bu kitap, iç çevre kalitesi (ses, ışık, ısıl konfor ve iç hava kalitesi) bileşenlerinin, uyku kalitesi ve ertesi gün sağlık ve zihinsel performansı üzerine günümüze kadar yapılan araştırmaların derlemesini ve değerlendirmesini içeren özgün çalışmalardan oluşmaktadır. Çalışmaların amacı, iç çevre parametrelerinin etkileri üzerine okuyucuya veyaşam alanı tasarımcılarına günümüz itibariyle bir çerçeve çizmek, ilgili araştırma alanlarını akademisyenlere tanıtmaktır.
Kitap şu bölümlerden oluşmaktadır: Bölüm 1: İÇ HAVA KALİTESİNİN UYKU KALİTESİNE VE ERTESİ GÜN SAĞLIK VE PERFORMANSINA ETKİSİ -
Macit Toksoy, Berrin Tuğrul, Sait Cemil Sofuoğlu
Bölüm 2: AKUSTİK KONFOR VE UYKU - Çağrı Şahin, Sait Cemil Sofuoğlu, Macit Toksoy
Bölüm 3: IŞIK VE UYKU - Begüm Can-Terzi, Sait Cemil Sofuoğlu, Macit Toksoy
Bölüm 4: ISIL KONFOR VE UYKU KALİTESİ - Sezgi Koçak Soylu, İbrahim Atmaca
Bölüm 5: UYKU ORTAMINDA İÇ ÇEVRE KALİTESİNİN HAD ANALİZİ İLE İNCELENMESİ ÜZERİNE BİR DERLEME - Nur Çobanoğlu, Ziya Haktan Karadeniz
Bölüm 6: KALİTELİ BİR UYKU İÇİN HAVALANDIRMANIN ÖNEMİ ve TASARIMI - Nur Çobanoğlu, Ziya Haktan Karadeniz, Sait Cemil Sofuoğlu, Macit Toksoy
... SLC is the difference between background noise and peak noise. A SLC cut-off ≥ 17.5 dB was used based on data from a prior study [14]. Meters were placed as close to the head of the patient's bed as possible. ...
... Average and peak noise levels contribute to background noise but may not be the source of sleep disruptions. Stanchina et al., using polysomnography in healthy subjects exposed to recordings of hospital noise, demonstrated that SLCs from baseline and not peak noise level determined whether a subject was aroused from sleep by noise [14]. In our study, patients in the single and shared room experienced a similar number of SLCs and therefore the same potential for arousal from sleep. ...
Objective
This study aimed to examine the environmental and operational factors that disrupt sleep in the acute, non-ICU hospital setting.Design, setting and participantsThis was a prospective study of adult patients admitted to an acute tertiary hospital ward (shared versus single room) and sleep laboratory (single room conducive to sleep).Main outcome measuresThis study measured ambient light (lux) and sound (dB), number of operational interruptions, and questionnaires assessing sleep and mental health.ResultsSixty patients were enrolled, 20 in a double bedroom located close to the nursing station (‘shared ward’), 20 in a single bedroom located distant to the nursing station (‘single ward’) and 20 attending the sleep laboratory for overnight polysomnography (‘sleep laboratory’). Sleep was disturbed in 45% of patients in the shared and single ward groups (Pittsburgh Sleep Quality Index > 5). Light levels were appropriately low across all 3 locations. Sound levels (significant effect of room F(1.38) = 6.452, p = 0.015) and operational interruptions (shared ward 5.6 ± 2.5, single ward 6.2 ± 2.9, sleep laboratory 2.7 ± 2.1 per night, p < 0.05 wards compared to sleep laboratory) were higher in the shared and single ward group compared to the sleep laboratory but not compared to each other. Noise was rated as the greatest environmental disturbance by 70% of ward patients compared to 10% in the sleep laboratory.Conclusion
Higher noise levels and frequent operational interruptions are potential barriers to sleep and recovery on an acute medical ward which are not ameliorated by being in a single bedroom located distant to the nursing station
... Broadband sounds (eg, white, brown, or pink sounds), ocean sounds, and music have all been attempted to reduce arousals from sleep and increase subjective sleep quality in critically ill patients, some with excellent effect. [17][18][19][20][21] The challenge with masking is there is a sound level at which the mask itself is not tolerated. One cannot increase masking indefinitely without the mask itself becoming annoying. ...
... Acoustic interruption (AI) is the difference between background sound levels and short, high sound spikes. We selected a difference of 17 dBA (A-weighted decibel) between average and peak sound levels as the value for defining AIs as this has previously been shown to cause an arousal from sleep [48]. ...
Background
ICU survival is improving. However, many patients leave ICU with ongoing cognitive, physical, and/or psychological impairments and reduced quality of life. Many of the reasons for these ongoing problems are unmodifiable; however, some are linked with the ICU environment. Suboptimal lighting and excessive noise contribute to a loss of circadian rhythms and sleep disruptions, leading to increased mortality and morbidity. Despite long-standing awareness of these problems, meaningful ICU redesign is yet to be realised, and the ‘ideal’ ICU design is likely to be unique to local context and patient cohorts. To inform the co-design of an improved ICU environment, this study completed a detailed evaluation of the ICU environment, focussing on acoustics, sound, and light.
Methods
This was an observational study of the lighting and acoustic environment using sensors and formal evaluations. Selected bedspaces, chosen to represent different types of bedspaces in the ICU, were monitored during prolonged study periods. Data were analysed descriptively using Microsoft Excel.
Results
Two of the three monitored bedspaces showed a limited difference in lighting levels across the day, with average daytime light intensity not exceeding 300 Lux. In bedspaces with a window, the spectral power distribution (but not intensity) of the light was similar to natural light when all ceiling lights were off. However, when the ceiling lights were on, the spectral power distribution was similar between bedspaces with and without windows. Average sound levels in the study bedspaces were 63.75, 56.80, and 59.71 dBA, with the single room being noisier than the two open-plan bedspaces. There were multiple occasions of peak sound levels > 80 dBA recorded, with the maximum sound level recorded being > 105 dBA. We recorded one new monitor or ventilator alarm commencing every 69 s in each bedspace, with only 5% of alarms actioned. Acoustic testing showed poor sound absorption and blocking.
Conclusions
This study corroborates other studies confirming that the lighting and acoustic environments in the study ICU were suboptimal, potentially contributing to adverse patient outcomes. This manuscript discusses potential solutions to identified problems. Future studies are required to evaluate whether an optimised ICU environment positively impacts patient outcomes.
... White noise has been extensively studied on sleep, mainly in infants and children (122), as well as intensive care unit patients (31,123), although, at high intensity, it has been revealed in rodents that white noises can be harmful to the organism, creating anxiety-like behaviors as well as inducing apoptosis, chromatolysis, cytoplasmic organelle destruction, and glial activation brain structures (153). Concerning studies on pain, a team compared the effect of an MRI scanner noise to white noises on the sensory-discriminative (i.e., intensity, localization) and the motivational-affective (i.e., unpleasantness) components of pain (11). ...
For the past two decades, using Digital Therapeutics (DTx) to counter painful symptoms has emerged as a novel pain relief strategy. Several studies report that DTx significantly diminish pain while compensating for the limitations of pharmacological analgesics (e.g., addiction, side effects). Virtual reality (VR) is a major component of the most effective DTx for pain reduction. Notably, various stimuli (e.g., auditory, visual) appear to be frequently associated with VR in DTx. This review aims to compare the hypoalgesic power of specific stimuli with or without a VR environment. First, this review will briefly describe VR technology and known elements related to its hypoalgesic effect. Second, it will non-exhaustively list various stimuli known to have a hypoalgesic effect on pain independent of the immersive environment. Finally, this review will focus on studies that investigate a possible potentialized effect on pain reduction of these stimuli in a VR environment.
... The use of PRN pulses makes MICNEST friendly to human ear. As drones may operate in populated areas, pulses should not cause acoustic discomfort, yet PRN has the same acoustic characteristics as white noise and is almost imperceptible to human ears [32], [33], [34]. Finally, MICNEST is resistant to impersonation attack, because pulses are (pseudo) randomly generated and it is difficult for third parties to generate the same pulse and impersonate a drone. ...
We present
MicNest
: an acoustic localization system enabling precise drone landing. In
MicNest
, multiple microphones are deployed on a landing platform in carefully devised configurations. The drone carries a speaker transmitting purposefully-designed acoustic pulses. The drone may be localized as long as the pulses are correctly detected. Doing so is challenging:
i)
because of limited transmission power, propagation attenuation, background noise, and propeller interference, the Signal-to-Noise Ratio (SNR) of received pulses is intrinsically low;
ii)
the pulses experience non-linear Doppler distortion due to the physical drone dynamics;
iii)
as location information is used during landing, the processing latency must be reduced to effectively feed the flight control loop. To tackle these issues, we design a novel pulse detector, Matched Filter Tree (MFT), whose idea is to convert pulse detection to a tree search problem. We further present three practical methods to accelerate tree search jointly. Our experiments show that
MicNest
can localize a drone 120 m away with 0.53% relative localization error at 20 Hz location update frequency. For navigating drone landing,
MicNest
can achieve a success rate of 94 %. The average landing error (distance between landing point and target point) is only 4.3 cm.
... This metric was chosen as sleep disruption is more likely to occur in the setting of brief bursts of sound rather than with a continuously loud background. 22 Patientspecific data were collected for each day of admission, including patient demographics, illness severity at admission (assessed by the PEdiatric Logistic Organ Dysfunction-2 [PELOD-2] score), use of mechanical ventilation, receipt of various medications (vasoactives, sedatives and analgesics, antipsychotics), and Richmond Agitation and Sedation Scale (RASS) scores (recorded every 4 hours). 23,24 Outcomes CAPD scores in our unit are standardly reported at 04:00 a.m. and 04:00 p.m. 21 Delirium was defined as a CAPD score 9 on at least 1 study day. ...
The purpose of this study was to evaluate the association between sound and light variables and development of delirium in pediatric intensive care unit (PICU) patients within the subsequent 3 days. Light and sound were continuously measured, and patient-specific data were collected daily. Outcomes included presence of delirium, determined by Cornell Assessment of Pediatric Delirium (CAPD) score ≥ 9 on at least 1 day, and development of delirium in the subsequent 3 days. One hundred and forty-two patients were enrolled, totaling 896 study days. Delirium prevalence was 31%. Neurologic diagnosis, younger age, longer PICU stay, restraints, benzodiazepines, opiate infusion, and dexmedetomidine were associated with delirium. Nighttime sound peaks (>70 and >80 dB) were not associated with delirium (p = 0.94 and 0.36, respectively). Light intensity during midday hours (12:00, 1:00, 2:00 pm) was not associated with the development of delirium (p=0.93, 0.81, 0.83, respectively), nor was maximum light at night, difference between maximum daytime and nighttime light, or between maximum and minimum daytime light (p = 0.15, 0.46, and 0.96, respectively). When adjusting for covariables, none of the sound or light variables was associated with delirium. Despite increasing awareness of pediatric delirium, data surrounding modifiable risk factors and concrete treatment strategies are lacking. We found no significant association between light or sound and development of delirium in PICU patients. However, there was little difference between daytime and nighttime light and sound, which may have impacted findings. As the etiology of delirium is multifactorial and potentially different for individual patients, targeted light/dark cycles warrant further study as they relate to delirium and critical illness.
... 5 Nonpharmacologic interventions, such as elimination of unnecessary noise and light, consolidation of patient care interactions, use of earplugs and eye masks, relaxation techniques, and addition of white noise, have been implemented to improve patients' sleep quality in the ICU. 6,7 However, the effects of these strategies are limited, and adjunctive drug therapy is often needed in some circumstances. 8 Dexmedetomidine has increasingly been used in ICU patients to improve sleep quality. ...
Purpose:
To examine whether nighttime dexmedetomidine infusion improved sleep quality in patients after laryngectomy.
Patients and methods:
Thirty-five post-laryngectomy patients admitted to the intensive care unit (ICU) were randomly assigned to a 9-h (from 2100 h on surgery day to 0600 h the morning after laryngectomy) dexmedetomidine (0.3 μg/kg/h continuous infusion) or placebo group. Polysomnography results were monitored during the dexmedetomidine infusion period. The percentage of stage 2 non-rapid eye movement (stage N2) sleep was the primary outcome measure.
Results:
Thirty-five patients (18 placebo group; 17 dexmedetomidine group) had complete polysomnogram recordings. The percentage of stage N3 sleep was significantly increased in the dexmedetomidine infusion group (from median 0% (0 to 0) in placebo group to 0% (interquartile range, 0 to 4) in dexmedetomidine group (difference, -2.32%; 95% CI, -4.19 to -0.443; P = 0.0167)). Infusion had no effect on total sleep time, stage N1 or N2 sleep percentages, or sleep efficiency. It decreased muscle tensity and snore non-rapid eye movement. Subjective sleep quality improved. Hypotension incidence increased in the dexmedetomidine group, but significant intervention was not required.
Conclusion:
Dexmedetomidine infusion improved overall patient sleep quality in the ICU after laryngectomy.
... The device was introduced to trainees in the PLA group through a 15-minute presentation, as a 'novel sleep-promoting device' that is emitting a frequency through antennas within a 20 m radius that will be detected by the brain and enhance sleep. The presentation cited previous research investigating other novel sleep devices, including devices that emit white noise (Forquer, Johnson, & Hypnosis, 2007), low energy emissions (Reite et al., 1994), and mixed-frequency white noise (Stanchina, Abu-Hijleh, Chaudhry, Carlisle, & Millman, 2005). The device was also introduced as being a betaproduct testing device that had not yet been studied, and given the nature of the invention, it was highly classified. ...
The manipulation of light exposure in the evening has been shown to modulate sleep, and may be beneficial in a military setting where sleep is reported to be problematic. This study investigated the efficacy of low‐temperature lighting on objective sleep measures and physical performance in military trainees. Sixty‐four officer‐trainees (52 male/12 female, mean ± SD age: 25 ± 5 years) wore wrist‐actigraphs for 6 weeks during military training to quantify sleep metrics. Trainee 2.4‐km run time and upper‐body muscular‐endurance were assessed before and after the training course. Participants were randomly assigned to either: low‐temperature lighting (LOW, n = 19), standard‐temperature lighting with a placebo “sleep‐enhancing” device (PLA, n = 17), or standard‐temperature lighting (CON, n = 28) groups in their military barracks for the duration of the course. Repeated‐measures ANOVAs were run to identify significant differences with post hoc analyses and effect size calculations performed where indicated. No significant interaction effect was observed for the sleep metrics; however, there was a significant effect of time for average sleep duration, and small benefits of LOW when compared with CON (d = 0.41–0.44). A significant interaction was observed for the 2.4‐km run, with the improvement in LOW (Δ92.3 s) associated with a large improvement when compared with CON (Δ35.9 s; p = 0.003; d = 0.95 ± 0.60), but not PLA (Δ68.6 s). Similarly, curl‐up improvement resulted in a moderate effect in favour of LOW (Δ14 repetitions) compared with CON (Δ6; p = 0.063; d = 0.68 ± 0.72). Chronic exposure to low‐temperature lighting was associated with benefits to aerobic fitness across a 6‐week training period, with minimal effects on sleep measures.
... Research showed that RS among autonomous sensory meridian response was able to induce sleep [12]. Nurse in the intensive care unit and coronary care unit was recommended to use WN because it prevents other noise [14], [15]. The monotonous task induced micro sleep [16]. ...
Sleep is an essential behavior to prevent the decrement of cognitive, motor, and emotional performance and various diseases. However, it is not easy to fall asleep when people want to sleep. There are various sleep-disturbing factors such as the COVID-19 situation, noise from outside, and light during the night. We aim to develop a personalized sleep induction system based on mental states using electroencephalogram and auditory stimulation. Our system analyzes users' mental states using an electroencephalogram and results of the Pittsburgh sleep quality index and Brunel mood scale. According to mental states, the system plays sleep induction sound among five auditory stimulation: white noise, repetitive beep sounds, rainy sound, binaural beat, and sham sound. Finally, the sleep-inducing system classified the sleep stage of participants with 94.7 percent and stopped auditory stimulation if participants showed non-rapid eye movement sleep. Our system makes 18 participants fall asleep among 20 participants.
... alre Another solution is using loudspeakers to mask environmental sounds using white noise. This has shown to have positive short-term effect on improving sleep quality [6] while recent studies suggest that prolonged exposure to noise from sound machines can induce auditory perceptual problems [7]. Instead of a static solution, where e.g. a white noise machine is either turned on the whole night or turned off with a timer, this calls for a more interactive solution. ...
Classifying sleep stages in real-time represents considerable potential, for instance in enabling interactive noise masking in noisy environments when persons are in a state of light sleep or to support clinical staff in analyzing sleep patterns etc. However, the current gold standard for classifying sleep stages, Polysomnography (PSG), is too cumbersome to apply outside controlled hospital settings and requires manual as well as highly specialized knowledge to classify sleep stages. Using data from Consumer Sleep Technologies (CSTs) to inform machine learning algorithms represent a promising opportunity for automating the process of classifying sleep stages, also in settings outside the confinements of clinical expert settings. This study reviews 27 papers that use CSTs in combination with Artificial Intelligence (AI) models to classify sleep stages. AI models and their performance are described and compared to synthesize current state of the art in sleep stage classification with CSTs. Furthermore, gaps in the current approaches are shown and how these AI models could be improved in the near-future. Lastly, the challenges of designing interactions for users that are asleep are highlighted pointing towards avenues of more interactive sleep interventions based on AI-infused CSTs solutions.
... watch?v=_CMzWGteDCY). White noise has the same intensity at all audible frequencies (10,17), unlike music, which is defined as an orderly arrangement of sounds consisting of melody, harmony, rhythm, tone, and pitch (18) (Supplemental Figure 1). We used headphones manufactured by JVC Kenwood Co. (Kanagawa, Japan) and tablet PCs by Bluedot Co. (Chiba, Japan). ...
Background and objectives
Pain during cannulation for vascular access is a considerable problem for patients with kidney disease who are undergoing hemodialysis. We examined whether listening to music can reduce cannulation pain in these patients.
Design, setting, participants, & measurements
We conducted a multicenter, single-blind, crossover, randomized trial of 121 patients who reported pain during cannulation for hemodialysis. We compared participants listening to “Sonata for Two Pianos in D Major, K.448” or white noise as control while undergoing the cannulation procedure. The cannulation operator was blinded to the intervention, and the hypothesized superiority of music over white noise was concealed during explanations to the participants. The primary end point was the visual analog scale score for cannulation pain independently evaluated by participants.
Results
The primary analysis was on the basis of the modified intention-to-treat principle. The median baseline visual analog scale pain score was 24.7 mm (interquartile range, 16.5–42.3). Median change of the visual analog scale pain score from the “no sound” to the music period was −2.7 mm (interquartile range, −9.2 to 3.6), whereas it was −0.3 mm (interquartile range, −5.8 to 4.5) from “no sound” to white noise. The visual analog scale pain score decreased when listening to music compared with white noise. (Adjusted difference of visual analog scale pain score: −12%; 95% confidence interval, −21 to −2; P =0.02.) There were no significant differences in the secondary outcomes of anxiety, BP, or stress assessed by salivary amylase (adjusted difference of visual analog scale anxiety score −8%, 95% confidence interval, −18 to 4; P =0.17). No intervention-related adverse events were reported.
Conclusions
Listening to music reduced cannulation pain in patients on hemodialysis, although there was no significant effect on anxiety, BP, or stress markers.
... Among the auditory stimuli used in the treatment, binaural beats are associated with a calm and positive affect and are known to reduce stress and anxiety [45,46], contributing to reduced pain perception. Studies also reported that nature-based sounds can promote relief, concentration, and asleep [47], especially by masking environmental noise [48,49] or by amplifying slow waves sleep [50,51]. Therefore, these auditory stimuli can help people with CPP and endometriosis relax and feel reduced pain. ...
Background
Chronic pelvic pain is a common and disabling condition in women living with endometriosis. Pharmacological and surgical treatments are not always effective at controlling pain and present important restrictions. Digital therapeutics (DTx) are emerging as major nonpharmacological alternatives that aim to extend the analgesic therapeutic arsenal of patients.
Objective
In this randomized controlled trial (RCT), we aimed to measure the immediate and 4-hour persisting effects of a single use 20-minute DTx (Endocare) on pain in women experiencing pelvic pain due to endometriosis.
Methods
A total of 45 women with endometriosis participated in a randomized controlled study comparing the analgesic effect of a single use of a virtual reality digital treatment named Endocare (n=23, 51%) to a 2D digital control (n=22, 49%). Perceived pain and pain relief were measured before the treatment and 15, 30, 45, 60, and 240 minutes after the end of the treatment.
Results
The clustered posttreatment pain was significantly reduced compared to the pretreatment for both Endocare and the control group (all P<.01). Endocare was significantly more effective than the control group (all P<.01). Endocare decreased the mean pain intensity from 6.0 (SD 1.31) before the treatment to 4.5 (SD 1.71) posttreatment, while the control only decreased it from 5.7 (SD 1.36) to 5.0 (SD 1.43). When comparing each posttreatment measures to the pretest, Endocare significantly reduced pain perception for all points in time up to 4 hours posttreatment. The differences did not reached significance for the control group. Moreover, Endocare was significantly superior to the control group 15, 30, and 45 minutes after the treatment (all P<.001). The mean perceived pain relief was significantly higher for Endocare at 28% (SD 2%) compared to the control, which was 15% (SD 1%) for all the posttreatment measurements (all P>.05).
Conclusions
Our study aimed to test the effects of a single use of a DTx treatment on reported pain at different time points in women diagnosed with endometriosis experiencing moderate-to-severe pelvic pain. Importantly, our results support that Endocare, a virtual reality immersive treatment, significantly reduce pain perception compared to a digital control in women living with endometriosis. Interestingly, we are the first to notice that the effect persisted up to 4 hours posttreatment.
Trial Registration
ClinicalTrials.gov NCT04650516; https://tinyurl.com/2a2eu9wv
... Unfortunately, there is a large degree of heterogeneity in studies of noise in the ICU, and it is currently impossible to quantify the extent to which noise contributes to sleep disruption and arousals among ICU patients [68]. Perhaps more important than absolute noise levels are changes in noise levels from baseline sound levels [68,72,73]. In this way, the sudden pump alarm may be more disturbing to a patient than the constant talking outside the room. ...
Purpose of Review
This article introduces fundamental concepts in circadian biology and the neuroscience of sleep, reviews recent studies characterizing circadian rhythm and sleep disruption among critically ill patients and potentially links to functional outcomes, and draws upon existing literature to propose therapeutic strategies to mitigate those harms. Particular attention is given to patients with critical neurologic conditions and the unique environment of the neuro-intensive care unit.
Recent Findings
Circadian rhythm disruption is widespread among critically ill patients and sleep time is reduced and abnormally fragmented. There is a strong association between the degree of arousal suppression observed at the bedside and the extent of circadian disruption at the system (e.g., melatonin concentration rhythms) and cellular levels (e.g., core clock gene transcription rhythms). There is a paucity of electrographically normal sleep, and rest-activity rhythms are severely disturbed. Common care interventions such as neurochecks introduce unique disruptions in neurologic patients. There are no pharmacologic interventions proven to normalize circadian rhythms or restore physiologically normal sleep. Instead, interventions are focused on reducing pharmacologic and environmental factors that perpetuate disruption.
Summary
The intensive care environment introduces numerous potent disruptors to sleep and circadian rhythms. Direct neurologic injury and neuro-monitoring practices likely compound those factors to further derange circadian and sleep functions. In the absence of direct interventions to induce normalized rhythms and sleep, current therapy depends upon normalizing external stimuli.
... Ces réveils sont également liés à l'environnement dans lequel se trouve la personne. En effet, une étude faite dans un service de soins intensifs prouve que le seuil entraînant un réveil augmente si une personne est déjà soumise à un bruit de fond continu et modéré (62 dB dans l'étude) comparé à un même bruit chez une personne non-exposée (Stanchina et al., 2005). ...
Avec le développement des nouvelles technologies, l'exposition aux champs électromagnétiques est de plus en plus importante. En marge de ce développement, nos sociétés ont vu émerger des personnes présentant des symptômes qu'ils attribuent à une exposition aux champs électromagnétiques. Les résultats des études expérimentales antérieurs restant à controverse, l'objectif de ce travail est de voir si une exposition conjointe entre les champs électromagnétiques et le bruit conduit à une apparition ou une exacerbation des symptômes des champs électromagnétiques. Cette étude s'est portée sur différentes fonctions physiologiques chez une population juvénile : le sommeil, le système immunitaire, la prise alimentaire, la respiration et le comportement. Nos résultats montrent un comportement anxieux, une diminution de la locomotion ainsi qu'une augmentation du poids des animaux, associé à des variations dans le pattern alimentaire. Le sommeil et la respiration sont peu modifiés chez les animaux exposés aux champs électromagnétiques. Le système immunitaire des animaux exposés aux champs électromagnétiques présente des altérations au niveau du système immunitaire acquis avec une redistribution des sous-populations lymphocytaires en faveur d'une activation des cellules et de l'immunité humorale, mais sans variation du système immunitaire inné. L'altération de ce dernier système est observée lors de la co-exposition mais est différente de celle d'une exposition au bruit. Ce travail de thèse a permis de mettre en évidence différents effets des CEM, notamment un comportement anxieux et des variations immunitaire
... Among the auditory stimuli used in the treatment, binaural beats are associated with a calm and positive affect and are known to reduce stress and anxiety [45,46], contributing to reduced pain perception. Studies also reported that nature-based sounds can promote relief, concentration, and asleep [47], especially by masking environmental noise [48,49] or by amplifying slow waves sleep [50,51]. Therefore, these auditory stimuli can help people with CPP and endometriosis relax and feel reduced pain. ...
BACKGROUND
Chronic pelvic pain is a frequent debilitating condition in women suffering from endometriosis. Pharmacological and surgical treatments are not always efficient in controlling pain and present important restriction. Digital Therapeutics (DTx) are emerging as major non-pharmacological alternatives, aiming to extend the analgesic therapeutic arsenal of the patients.
OBJECTIVE
In this randomized controlled trial (RCT), we aimed to measure the immediate and 4 hours persisting effects of a single use 20-minutes long DTx (Endocare) on pain in women suffering from pelvic pain related to endometriosis.
METHODS
Forty-five women suffering from endometriosis participated in a randomized controlled study comparing the analgesic effect of a single use of a virtual reality digital treatment (Endocare, n = 23) to a 2D digital control (n = 22). Perceived pain and pain relief were measured before the treatment and 15-, 30-, 45-, 60-, and 240-minutes after the end of the treatment.
RESULTS
The clustered post-treatment pain is significantly reduced compared to the pretreatment for both Endocare and the control group (all P<.01). Endocare was significantly more efficient than the control group (all P<.01). When comparing each post-treatment measures to the pretest, Endocare significantly reduces pain perception for all times up to 4 hours post-treatment. The differences didn’t reached significance for the control group. Moreover, Endocare was significantly superior to the control group for 15-, 30- and 45-minutes after the treatment (all P<.001). The mean perceived pain relief was significantly higher for Endocare compared to the control for all the post-treatment measurements (all P>.05).
CONCLUSIONS
To our knowledge, our study is the first to test the effects of a single use of a DTx treatment on reported pain at different time points in patients diagnosed with endometriosis perceiving moderate-to-severe pelvic pain. Importantly, our result supports that Endocare, a VR immersive treatment, significantly reduce pain perception compared to a digital control in women suffering from endometriosis. Interestingly, we are the first to notice the effect persisted up to 4 hours post-treatment.
CLINICALTRIAL
ClinicalTrials.gov NCT04650516
... [17] As a background sound, white noise can also change the auditory threshold and thereby reduce brain stimulation and anxiety levels. [18] White noise reduces patient's anxiety and, depending on the duration of exposure, the functions of this noise may be variable. [12,13] Suction machine is one of the indispensable devices in the operating room. ...
Aim: Anxiety reduces performance at work. Anxiety is significantly prevalent among medical staff in general, and especially operating room staff. The present study was an attempt to investigate the effect of suction-induced white noise on anxiety and hemodynamic parameters of operating room staff during cesarean section. Materials and Methods: The present study was a crossover, single-blind clinical trial on 29 scrub staff during cesarean section. The subjects were assigned once to the control group and once to the intervention group with a 10-day washout period. In the intervention group, the suction machine was left on during surgery for 3 days in a row, but in the control group, the suction machine was switched off in idle times to make sure that noise exposure time would remain below 30 min. Hemodynamic parameters of subjects were measured on the last day immediately after surgery, and the Spielberger State-Trait Anxiety Inventory was used to measure the level of anxiety. SPSS 22 software and linear mixed model were used to analyze the collected data. Results: The control and intervention groups were not significantly different in terms of hemodynamic parameters, anxiety as well as the carryover-crossover effects (P > 0.05). A significant negative correlation was observed between anxiety score and age of the subjects (P < 0.05). Conclusions: Suction-induced white noise has no effect on anxiety and hemodynamic parameters of operating room staff. Adaptation to workplace noises can reduce the adverse effects of noise.
... Εναλλακτικά, µπορεί να µειωθεί η ενόχληση που προκαλεί ο θόρυβος µε χρήση µουσικής ή ωτοασπίδων. Ευεργετικά αποτελέσµατα στην προαγωγή του ύπνου των ασθενών που εκτίθενται στο θόρυβο της ΜΕΘ έχει ο «λευκός θόρυβος» (Stanchina et al 2005). ...
Introduction: Providing high quality care in todays’ Intensive Care Units is a challenge because of the constant increase in demand, the high functional cost and the restricted availability of resources. Evaluating both patients’ experiences and outcomes from the care provided is necessary for ensuring high quality in health care. Aim: The investigation of patient reported experiences in Intensive Care Units and the evaluation of their health related quality of life six to twelve months after discharge. Methods: It is a non-interventional cross-sectional study with retrospective data collection. The participants were 108 patients, discharged from four Intensive Care Units of three military hospitals in Athens. Telephone interviews were conducted using “Patient Empowerment Questionnaire” and “Quality of life Questionnaire” to evaluate patients’ experiences and health related quality of life respectively. Statistical analysis was conducted using the statistical package SPSS v.25.0. Results: The majority of the study population reported positive experiences with the critical care staff and normal quality of life after discharge. However, 47% reported that they could not always sleep at night and 32% did not always receive adequate pain relief. In regards to patients’ quality of life, “normal daily activities” were affected the most. Specifically, half of the patients reported inability to carry out activities requiring high level of physical effort and 1/5 expressed difficulties in walking and in mobility. Additionally, 43% reported difficulties in the job or their daily activities, have changed or completely abandoned them. Conclusions: The patients’ positive experiences and good health related quality of life after discharge gave the impression that quality of intensive care in Greek military hospitals is high. Interventions intending to achieve more adequate pain relief, better sleep at night, and prevention of critical illness’ negative impact on day-to-day activities would ensure more positive results.
... For instance, tonal noise found in our living, working, and hospital environments is a nuisance at best leading to serious health issues 42 . As a contrast, clinical trials show that random noise (white or pink) promotes sleep for the neonates 43 , patients in intensive care unit 44 , and coronary care unit 45 . ...
Wave frequency is a critical parameter for applications ranging from human hearing, acoustic non-reciprocity, medical imaging to quantum of energy in matter. Frequency alteration holds the promise of breaking limits imposed by the physics laws such as Rayleigh's criterion and Planck-Einstein relation. We introduce a linear mechanism to convert the wave frequency to any value at will by creating a digitally pre-defined, time-varying material property. The device is based on an electromagnetic diaphragm with a MOSFET-controlled shunt circuit. The measured ratio of acoustic impedance modulation is up to 45, much higher than nonlinearity-based techniques. A significant portion of the incoming source frequency is scattered to sidebands. We demonstrate the conversion of audible sounds to infrasound and ultrasound, respectively, and a monochromatic tone to white noise by a randomized MOSFET time sequence, raising the prospect of applications such as super-resolution imaging, deep sub-wavelength energy flow control, and encrypted underwater communication.
... Admission to the intensive care unit (ICU) is considered a stressful phenomenon in a person's life since it indicates the existence of a serious and life-threatening problem (1). Factors exacerbating the patient's stress and anxiety in ICU include sleeplessness, shortness of breath, inability to move, painful medical interventions such as endotracheal tubes, nasogastric tubes, as well as disturbing sound in the ICU produced by ventilators, medical equipment, and staff's routine activities (2). Part of this stress and anxiety is also caused by patients' lack of access to family members (3). ...
Background: One of the main stressors for patients admitted to the intensive care unit (ICU) is being away from family members and severe appointment time limits. Currently, the treatment environment is made of family members and patients, and the presence of family members plays an important role in the patient’s health. Objective: This study aimed to determine the effect of scheduled family appointments on the agitation of ICU patients. Methods: This quasi-experimental study was performed on 70 patients admitted to the ICU of medical centers affiliated to Zahedan University of Medical Sciences, Iran, in 2020. The patients were selected using convenience sampling from among those who met the inclusion criteria. The selected patients were randomly assigned into two equal groups of control and intervention (n = 35 in each). The patients in the control group were visited via routine appointments. In contrast, the patients in the intervention group were visited both routinely and via scheduled appointments by a fixed member of the family for 20 minutes at 10-12 AM and 8-10 PM for three days. The data were collected using a demographic information form and Richmond Agitation Sedation Scale (RASS), which was completed by the researcher for each patient on the first day before and the third day after the intervention. The collected data were analyzed using IBM SPSS software (version 24) with the chi-square test, Fisher’s exact test, independent samples t-test, and Mann–Whitney U test. The significance level was considered less than 0.05. Results: The two groups were similar in terms of age, sex, level of consciousness, and history of hospitalization in the ICU and there was no statistically significant intergroup difference (P > 0.05). According to the results of Mann–Whitney U and chi-square tests, there was a significant difference between the groups in terms of agitation at the end of the study (P < 0.05). Conclusions: Scheduled appointments for ICU patients can reduce patients’ agitation without affecting nurses’ care activities. This accelerates the recovery process for patients. Hence, the appointment-based policy needs to be implemented in ICUs.
... 22,23 Patients admitted to the ICU frequently attribute noise and disturbance overnight to their poor sleep 24-28 and a recent review has shown the risk of developing delirium in the ICU can be reduced by giving earplugs to patients. 29 This suggests that despite the development of delirium in the ICU being associated with severity of illness and some drug treatments, 11 and studies recognising that just 11-17% of arousals overnight can be attributed to noise, [30][31][32] sleep and noise do have a role to play in the physical and psychological recovery of patients admitted to the ICU. 10 The high temporal fidelity of sound level monitoring highlighted the 24 h pattern previously identified. 4 This demonstrates clearly that sound levels fluctuate more than daily mean values indicate. ...
Background
Intensive care units are significantly louder than WHO guidelines recommend. Patients are disturbed by activities around them and frequently report disrupted sleep. This can lead to slower recovery and long-term health problems. Environmental sound levels are usually reported as LAeq24, a single daily value that reflects mean sound levels over the previous 24-h period. This may not be the most appropriate measure for intensive care units (ICUs) and other similar areas. Humans experience sound in context, and disturbance will vary according to both the individual and acoustic features of the ambient sounds. Loudness is one of a number of measures that approximate the human perception of sound, taking into account tone, duration, and frequency, as well as volume. Typically sounds with higher frequencies, such as alarms, are perceived as louder and more disturbing.
Methods
Sound level data were collected from a single NHS Trust hospital general adult intensive care unit between October 2016 and May 2018. Summary data (mean sound levels (LAeq) and corresponding Zwicker calculated loudness values) were subsequently analysed by minute, hour, and day.
Results
The overall mean LAeq24 across the study duration was 47.4 dBA. This varied by microphone location. We identified a clear pattern to sound level fluctuations across the 24-h period. Weekends were significantly quieter than weekdays in statistical terms but this reduction of 0.2 dB is not detectable by human hearing. Peak loudness values over 90 dB were recorded every hour.
Conclusions
Perception of sound is sensitive to the environment and individual characteristics and sound levels in the ICU are location specific. This has implications for routine environmental monitoring practices. Peak loudness values are consistently between 90 and 100 dB. These may be driven by alarms and other sudden high-frequency sounds, leading to more disturbance than LAeq24 sound levels suggest. Addressing sounds with high loudness values may improve the ICU environment more than an overall reduction in the 24-h mean decibel value.
... The Effect of White Noise on Sleep 취하였다고 보고하였다 [5]. 이러한 [14], 관상 동맥질환 입원 환자들의 수면의 질이 향상되었으며 [13], 국내 에서는 대학생들의 수면의 질이 향상되고, 우울 및 스트레스 점 수가 낮아졌다 [12]. 이 외에도 백색소음은 주의집중력, 기억력 향상에도 효과적인 것으로 나타났다 [18]. ...
Il tema del congresso Aniarti 2009 intende esplicitamente essere una proposta culturale per il sistema della salute e dell’assistenza così come lo conosciamo e di cui non siamo soddisfatti.Tutto il mondo si sta interrogando sulla sostenibilità del proprio futuro e sulle strade da percorrere per non arrivare troppo tardi...Siamo ormai tutti consapevoli della necessità di una nuova interpretazione del nostro modo di vivere, del modo di intendere la salute, di operare ed organizzarsi per proteggerla, del modo di usare le risorse in genere e di quelle per la salute in particolare.Sono palesemente insufficienti ed a volte drammatici, i risultati di applicazioni di scienza e tecnologia alle patologie, senza considerare l’uomo nella sua maturazione odierna.La smania di un malinteso progresso ci ha portati a limiti estremi che, malgestiti, sono diventati pericolosi.Nell’assistenza in area critica si toccano con mano problemi esistenziali cruciali non solo per i singoli, ma per l’intera comunità ; problemi di limitazione delle libertà , di ingiustizia e colpevoli disequità .Devono essere trovate ed inevitabilmente imboccate strade nuove che riescano a coniugare i nostri valori fondativi con le nuove conoscenze e le recentissime possibilità tecniche.Si impone l’urgenza di darci un limite nuovo ed intelligente, di rimodulare un concetto di progresso.Questo non significa necessariamente rinunciare all’evoluzione: significa fare tutto questo meglio e con maggiore correttezza, con la consapevolezza che gli effetti ricadono sulle persone e sulle comuni- tà . Le conseguenze delle strade che si intraprendono vanno previste e le risposte vanno cercate e fornite.Gli infermieri sono quotidiani protagonisti del modo in cui oggi si coniugano le risorse a disposizione con le possibilità che scienza e tecnologia offrono per risolvere i problemi di salute. Sono protago- nisti nel far acquisire consapevolezza, dignità e libertà all’uomo.
Objective
The goal of this randomized, double-blinded, placebo-controlled study was to evaluate the effect of environmental enrichment (EE) on post-operative pain and anxiety in dogs following hemilaminectomy for acute intervertebral disc extrusion (IVDE).
Methods
Twenty healthy client-owned dogs undergoing a hemilaminectomy for IVDE with the same immediate post-operative analgesia protocol were randomly assigned to either the EE or standard environment (SE) group post-operatively. Recovery was achieved in an intensive care room (SE) or a separate quiet room (EE) equipped with white noise and classical music. EE dogs were also exposed to dog-appeasing pheromones, essential oil scents, and positive human interactions and were provided meals through food toys. A blinded evaluator assessed all dogs using the modified Glasgow Composite Pain Scale (mGCPS) on presentation and at several time points post-operatively. A rescue injection of the opioid methadone was given to the dogs with an mGCPS score of ≥5/20. Dogs received the antidepressant trazodone when anxious behaviors (5 mg/kg) were observed. The mGCPS scores, the latencies to receive the first methadone and trazodone doses and to eat the first meal, the number of methadone and trazodone doses, and the number of meals ingested in the first 24 and 48 h post-surgery were compared using Wilcoxon tests, and Benjamini–Hochberg correction for false discovery rate was applied.
Results
Although median mGCPS scores did not differ between the groups, compared to SE dogs ( n = 10), EE dogs ( n = 6) received trazodone earlier ( p = 0.019), were administered fewer methadone injections at 24 h ( p = 0.043), and ate more at 48 h post-surgery ( p = 0.007). Therefore, EE and anti-anxiety medications could be beneficial in improving the wellbeing of dogs post-operatively.
We present MicNest: an acoustic localization system enabling precise landing of aerial drones. Drone landing is a crucial step in a drone’s operation, especially as high-bandwidth wireless networks, such as 5G, enable beyond-line-of-sight operation in a shared airspace and applications such as instant asset delivery with drones gain traction. In MicNest, multiple microphones are deployed on a
landing platform in carefully devised configurations. The drone carries a speaker transmitting purposefully-designed acoustic pulses. The drone may be localized as long as the pulses are correctly detected. Doing so is challenging: i) because of limited transmission power, propagation attenuation, background noise, and propeller interference, the Signal-to-Noise Ratio (SNR) of received pulses
is intrinsically low; ii) the pulses experience non-linear Doppler distortion due to the physical drone dynamics while airborne; iii) as location information is to be used during landing, the processing latency must be reduced to effectively feed the flight control loop. To tackle these issues, we design a novel pulse detector, Matched
Filter Tree (MFT), whose idea is to convert pulse detection to a tree search problem. We further present three practical methods to accelerate tree search jointly. Our real-world experiments show that MicNest is able to localize a drone 120 m away with 0.53% relative localization error at 20 Hz location update frequency.
Background Noise in intensive care units (ICUs) has always been a problem, but noise above the recommended range affects not only the patient but staff as well. It is clear that some noise in the ICU is inevitable, but exceeding the normal range brings various physiologic and psychologic changes, which directly affect health. This review presents a synthesis of noise sources in the ICU and the potential interventions designed to attenuate noise and protect patients.
Materials and Methods An extensive literature search, using electronic databases such as MEDLINE, PubMed, Google Scholar, and Research gate to understand the noise in ICU, effects of noise, and noise reduction interventions were undertaken.
Results Findings were such as noise enhances the release of cortisol, increases oxygen consumption, increases sleep disturbances, increases the need for analgesia and sedation, and disrupts circadian rhythm. Many studies reported that measurement was always higher despite implementing noise reduction interventions.
Conclusions ICU survivors always recall their memories, and for them, ICU admission becomes a negative experience for life. However, the sustainability of any single intervention did not show awe-inspiring results, whereas a bundle kind of interventions did show some effects. However, high-quality evidence demonstrating the benefit of any intervention on patient outcomes is still lacking.
Keywords: Health, health professionals, intensive care unit, intervention, noise, noise control, noise prevention, patients
Auditory white noise (WN) is widely used in neuroscience to mask unwanted environmental noise and cues, e.g. TMS clicks. However, to date there is no research on the influence of WN on corticospinal excitability and potentially associated sensorimotor integration itself. Here we tested the hypothesis, if WN induces M1 excitability changes and improves sensorimotor performance. M1 excitability (spTMS, SICI, ICF, I/O curve) and sensorimotor reaction‑time performance were quantified before, during and after WN stimulation in a set of experiments performed in a cohort of 61 healthy subjects.
WN enhanced M1 corticospinal excitability, not just during exposure, but also during silence periods intermingled with WN, and up to several minutes after the end of exposure. Two independent behavioural experiments highlighted that WN improved multimodal sensorimotor performance. The enduring excitability modulation combined with the effects on behaviour suggest that WN might induce neural plasticity. WN is thus a relevant modulator of corticospinal function; its neurobiological effects should not be neglected and could in fact be exploited in research application
Nowadays, increasing number of people are facing insomnia due to the work-rest balance difficulties in their daily life, while most of them are not in a serious situation. Hence, non-pharmaceutical treatment for insomnia is becoming a more popular method as the people’s preference, and new products are emerging in this field regarding such tendency. Therefore, this study makes a general analysis of the current products and as a result, it is found that 1) Melatonin and brain waves are central to their intervention principles; 2) The user interacts with the product in a passive manner and can only act as a receiver of the intervention signal. Moreover, in order to improve such situation, we further propose an alternative direction in accessing a health monitoring system with artificial intelligence in this paper. Through the health monitoring system to obtain user data and artificial intelligence to learn from the data, one can make the product adjust to the user’s treatment, forming a closed loop.
Despite the need for rest and recovery for acutely ill patients, hospitalized patients are often at risk for disrupted sleep due to a variety of factors. Whether it be from routine medical care, suboptimal environments due to noise or light, or patient care factors such as symptoms, hospitalized patients face both acute and chronic sleep loss from being in the hospitalization. Sleep loss in the hospital contributes a variety of cardiometabolic and neurologic derangements and is also a factor that increases the risk of “post-hospital syndrome,” or an acquired vulnerability after hospitalization that is associated with all cause readmissions. Interventions to improve sleep loss for hospitalized patients are warranted.
Hospitalization is a period of acute sleep deprivation for older adults due to environmental, medical, and patient factors. Although hospitalized patients are in need of adequate rest and recovery during acute illness, older patients face unique risks due to acute sleep loss during; hospitalization. Sleep loss in the hospital is associated with worse health outcomes, including; cardio-metabolic derangements and increased risk of delirium. Because older patients are at risk of; polypharmacy and medication side effects, a variety of nonpharmacological interventions are recommended first to improve sleep loss for hospitalized older adults.
In this narrative review, we summarize recent research on the prognostic significance of biomarkers of sleep in continuous EEG and polysomnographic recordings in intensive care unit patients. Recent studies show the EEG biosignatures of non-rapid eye movement 2 sleep (sleep spindles and K-complexes) on continuous EEG in critically ill patients better predict functional outcomes and mortality than the ictal-interictal continuum patterns. Emergence of more complex and better organized sleep architecture has been shown to parallel neurocognitive recovery and correlate with functional outcomes in traumatic brain injury and strokes. Particularly interesting are studies which suggest intravenous dexmedetomidine may induce a more biomimetic non-rapid eye movement sleep state than intravenous propofol, potentially providing more restorative sleep and lessening delirium. Protocols to improve intensive care unit sleep and neurophysiological studies evaluating the effect of these on sleep and sleep architecture are here reviewed.
Study objectives:
Auditory stimulation devices (white and pink noise) are used to mask sounds and facilitate relaxation and sleep; however, the effectiveness of this intervention is not well established. This systematic review examined the scientific literature for the effect of specific types of auditory stimulation on sleep outcomes in adults.
Methods:
The PRISMA Statement guided this review. Searches were conducted in nine databases for intervention studies that could easily be employed in clinical practice. We excluded other types of auditory stimulation (music alone, binaural tones, and synchronization). Two reviewers screened abstracts and full-text articles for eligibility, with conflicts resolved by a third reviewer, and extracted data. Risk of bias was assessed with the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies.
Results:
34 studies reported results of 1,103 persons participating in three categories of interventions: white noise (18), pink noise (11), and six multi-audio (some combination of white, pink, music, or silence). Nineteen studies had positive findings in terms of improving sleep outcomes: 6 white noise (33%), 9 pink noise (81.9%), and 4 multi-audio (66.7%). Multi-audio had the lowest (better) risk of bias (mean/SD: 1.67/0.82) compared to white (2.38/0.69) and pink noise (2.36/0.81).
Conclusions:
Although there was no strong evidence to support use of auditory stimulation, none of the studies reported any adverse effects with short-term application of auditory stimulation during sleep. Future research needs to include confounding factors that can affect outcomes, including one's noise sensitivity, personality, and other conditions or medications that may affect sleep.
Background
Sleep disturbance negatively affects recovery and survival of patients in intensive care units (ICUs).
Aims and Objectives
This study aimed to measure the noise levels and evaluate the impact of a white noise app on the sleep quality of critically ill patients.
Design
A quasi-experimental time series pre-test–post-test control group design with repeated measures was adopted.
Methods
The study was conducted in the high dependency unit (HDU) of a selected tertiary care hospital in Mangalore, Karnataka State, India. Conscious oriented patients with systolic blood pressure ranging from 100/70 to 140/90 mm Hg and hearing acuity of at most 20 dB in both ears were included in the study. Noise levels in the HDU were measured using calibrated sound level meter on weekdays/weekends in three different shifts and an average of 24 readings was obtained per shift. A 4-point Likert scale was used to assess the sleep quality. The intervention included administration of white noise app twice a day, for three consecutive days by using different masking sounds such as white noise on day 1 which resembles to a humming AC conditioner, pink noise on day 2 which resembles to the sound of ocean waves and brown noise on day 3 which resembles a steady rainfall. The app was used with the help of JBL earphones C10SI an excellent noise cancellation and noise isolating earphone.
Results
Among the 54 subjects, the mean age of the patients was 40.28 years, majority 34 (63%) were males. The noise level in the ICU was more than 60 dB. There was a significant difference in the sleep quality after the application of the white noise app in the experimental group on Day 1 (Z = −3.996; P = .001), Day 2 (Z = −3.302; P = .001), and Day 3 (−2.822; P = .005) compared to the control group.
Conclusion
Adoption of technology driven noise reduction applications would enhance the quality of sleep among the ICU patients.
Relevance to clinical practice
The use of a technology-driven application helps control noise levels which promotes improved sleep quality among critically ill patients in the intensive care units.
Background
There is a growing body of research that identifies sound levels in an intensive care unit to be higher than current recommendations; although the quality and reproducibility of these studies has been questioned. Noise is generated by the multiplicity of supportive equipment necessary for patient management and by the staff who provide or enable care. Patients remember noise as a prominent and sometimes distressing feature of their intensive care admission. There is currently no study that provides a robust description of the sources of noise in an intensive care unit. Therefore, the aim of this study was to identify the sources of sound and their relative contribution to the sound environment of an intensive care unit.
Methods
Fifty hours of observational data were collected over a month, using a datasheet designed and piloted for this purpose. Data was collected at four bed spaces, providing equal representation across each bed space, hour of the day and day of the week. A priori, five categories of sound were identified, communication, clinical tasks, housekeeping tasks, alarms and miscellaneous; 55 individual sources of sound were reported under these categories. Concurrently, continuous sound pressure levels were monitored at each bed space.
Results
16,784 episodes of sound were identified during the 50hrs of data collection; the greatest number of episodes were reported in the communication category n = 5699 (34%), with clinical tasks n = 3282 (20%), housekeeping tasks n = 3247 (19%), alarms n = 2939 (18%) and miscellaneous n = 1617 (10%). The highest number of episodes for an individual sound source was nurse/nurse communication n = 1595 (10%), followed by bin lids n = 1004 (6%) and oxygen/nebulisers n = 945 (6%). Of the 55 sources recorded, the top 25 accounted for 86% of the episodes. The average SPL (LAeq50hrs) across all bed-spaces during this study was 65.1 dB (SD 3.98) with little variation between day (66.3 dB; SD 3.37) and night time (62.7 dB; SD 3.81), The four bed spaces demonstrated difference in average LAeq, with the nosiest being the single room (LAeq12hrs69.1 dB, SD 1.98); and the quietest bed space 5 in an open bay (LAeq13hrs59.8 dB, SD 2.49).
Conclusion
Concurrent observational and quantitative data collection enabled detailed analysis of the sound environment. The results provide greater clarity than previous study, into the individual sound sources and their relative contribution to the noise environment of an intensive care unit. This information will help identify which sources of sound are most amenable to modification. There is a need for further study to understand the perception of noise in an intensive care unit, by its main users; the patients, staff and visitors. Current SPL guidance appears unachievable without a change in ambient sound levels.
The bedroom environment has varied across time and cultures. Cumulating research suggests that the ideal bedroom environment is dark, quiet, and cool. The present chapter examines the bedroom environment through the lenses of four of our senses: vision, touch, hearing, and smell. We begin with a discussion of the historical evolution of the bedroom environment. Then, the role of each of the four senses is examined in terms of promoting healthy sleep. We end with an overview of cultural considerations that can affect the bedroom environment.
Delirium, a disorder characterized by altered consciousness, inattention, and global disturbance in cognition, is a common syndrome in the intensive care unit (ICU), affecting up to 90% of critically ill patients. Over the past 20 years, ICU delirium has gained substantial attention as a major health problem, due to its high prevalence and association with adverse patient outcomes including prolonged length of stay, long-term cognitive, physical, and mental health impairments, and early death. The pathophysiology of delirium is complex and poorly understood, with a number of potential mechanisms and pathways. Prevention and early identification of delirium, using multicomponent strategies and validated bedside tools, respectively, are vital for management efforts. Clinical practice guidelines for delirium prevention and treatment recommend the emphasis on routine screening for delirium, protocol-driven assessment and management of analgesia and sedation, sleep promotion, minimization of provoking factors, and the importance of early rehabilitation and mobility. As the topic of ICU delirium is extensive, this chapter will focus specifically on (1) pathophysiology; (2) presentation; and (3) prevention and management strategies of delirium.
Exposure to noise from road traffic and industries is known to be linked to various health dysfunctions, including hypertension, cardiovascular diseases and hearing loss. Exposure to artificial light at night (ALAN) is also increasingly recognized as being associated with ecosystem damage and various illnesses, including cancers, excessive weight gain and sleep disorders. However, measuring and monitoring these environmental risk factors by professional equipment are laborious and expensive, which impede large-scale research and various citizen science initiatives. In this study, we test a possibility that reliable noise and ALAN exposure estimates can be gathered using smartphones (SPs) sensors. To verify this assumption, we develop a standardized testing protocol, and use Andro-Sensor app, installed on three different Samsung Galaxy SPs – S7, S20FE5G, and SM520F, – to perform measurements of ALAN and noise in real-world conditions while comparing these measurements with measurements performed by professional (type 2) equipment – SL814 for noise and LX-1330B for illumination. The analysis of 3450 measurements, performed in two different locations in Israel, reveals that the SPs measurements and measurements performed by control instruments correlate strongly for noise (r = 0.76–0.94) and are nearly identical for ALAN (r = 0.998–0.999). The association between the two types of measurements is also found to be close to linear, with the slope of the trend line being close to 45° for ALAN and varying between 30° and 45° for noise, depending on the SPs used. Our conclusion is that the level of accuracy of ALAN measurements by SPs is greater for ALAN than for noise, which can make SPs a useful tool for large-scale ALAN studies that do not require the accuracy of professional instruments.
Introduction
Undisturbed sleep has been shown to be important for both health and quality of life¹. The World Health Organization estimates that nearly 25% of the population suffers from disturbed sleep due to environmental noise². Sleep disturbance associated with elevated noise levels is particularly prevalent in metropolitan areas. Our study tested the hypothesis that white noise would improve sleep in New Yorkers complaining of sleep difficulty due to elevated sound levels.
Methods
Ten adult participants were included in this study. All participants were recruited from a New York City based sleep clinic. Inclusion criteria was based on the presence of sleep disturbance and the reporting of high levels of environmental noise in participants’ sleep location. The study was conducted using a within-subject, ABA design, with baseline, treatment phase, followed by another baseline (washout) period. Each phase lasted one-week, during which noise level and sleep were assessed. The treatment consisted of the application of a white noise device (Dohm Classic by Marpac, LLC) in the participants’ bedroom. Sleep parameters were measured subjectively using the Consensus Sleep Diary³, and objectively using a Motionlogger Actigraph.
Results
Paired sample t-tests were conducted to evaluate the hypothesis that white noise improves sleep in a high noise environment. Significance was found on the variables WASO, as measured by actigraphy, t(9) = 3.438, p = 0.007 and sleep latency as measured by sleep diary, t(9) = 2.947, p = 0.016. There was a trend toward significance on the number of awakenings during the night, as measured by sleep diary, t(9) = 2.622, p = 0.028 (Holm’s sequential correction of p-value required a value of <0.01 to find significance on this comparison) and sleep efficiency (actigraph), t(9) = -2.121, p = 0.063.
Conclusion
Our data show that white noise significantly improved sleep based on subjective and objective measurements in subjects complaining of difficulty sleeping due to high levels of environmental noise. This suggests that the application of white noise may be an effective tool in helping to improve sleep in those settings.
Sleep deprivation and fragmentation occurring in the hospital setting may have a negative impact on the respiratory system by decreasing respiratory muscle function and ventilatory response to CO2. Sleep deprivation in a patient with respiratory failure may, therefore, impair recovery and weaning from mechanical ventilation. We postulate that light, sound, and interruption levels in a weaning unit are major factors resulting in sleep disorders and possibly circadian rhythm disruption. As an initial test of this hypothesis, we sampled interruption levels and continuously monitored light and sound levels for a minimum of seven consecutive days in a medical ICU, a multiple bed respiratory care unit (RCU) room, a single-bed RCU room, and a private room. Light levels in all areas maintained a day-night rhythm, with peak levels dependent on window orientation and shading. Peak sound levels were extremely high in all areas representing values significantly higher than those recommended by the Environmental Protection Agency as acceptable for a hospital environment. The number of sound peaks greater than 80 decibels, which may result in sleep arousals, was especially high in the intensive and respiratory care areas, but did show a day-night rhythm in all settings. Patient interruptions tended to be erratic, leaving little time for condensed sleep. We conclude that the potential for environmentally induced sleep disruption is high in all areas, but especially high in the intensive and respiratory care areas where the negative consequences may be the most severe.
To objectively measure sleep in critically ill patients requiring mechanical ventilation and to define selection criteria for future studies of sleep continuity in this population.
Prospective cohort analysis.
University teaching hospital medical-surgical ICU.
Twenty critically ill (APACHE II [acute physiology and chronic health evaluation II] acute physiology score [APS], 10 +/- 5), mechanically ventilated adults (male 12, female 8, age 62 +/- 15 years) with mild to moderate acute lung injury (lung injury score, 1.8 +/- 0.9) 10 +/- 7 days after admission to the ICU.
Patients were divided into three groups based on 24-h polysomnography (PSG) findings. No patient demonstrated normal sleep. In the "disrupted sleep" group (n = 8), electrophysiologic sleep was identified and was distributed throughout the day (6:00 AM to 10:00 PM; 4.0 +/- 2.9 h) and night (10:00 PM to 6:00 AM; 3.0 +/- 1.9 h) with equivalent proportions of non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Nocturnal sleep efficiency was severely reduced (38 +/- 24%) with an increased proportion of stage 1 NREM sleep (40 +/- 28% total sleep time [TST]) and a reduced proportion of REM sleep (10 +/- 14% TST). Severe sleep fragmentation was reflected by a high frequency of arousals (20 +/- 17/h) and awakenings (22 +/- 25/h). Electrophysiologic sleep was not identifiable in the PSG recordings of the remaining patients. These were classified either as "atypical sleep" (n = 5), characterized by transitions from stage 1 NREM to slow wave sleep with a virtual absence of stage 2 NREM and reduced stage REM sleep, or "coma" (n = 7), characterized by > 50% delta or theta EEG activity with (n = 5) and without (n = 2) evidence of EEG activation either spontaneously or in response to deep painful stimuli. The combined atypical sleep and coma groups had a higher APS (13 +/- 4 vs 6 +/- 4) and higher doses of sedative medications than the disrupted sleep group.
Sleep, as it is conventionally measured, was identified only in a subgroup of critically ill patients requiring mechanical ventilation and was severely disrupted. We have proposed specific criteria to select patients for future studies to evaluate potential causes of sleep disruption in this population.
Auditory evoked potentials were recorded during wakefulness, Stage 1, and Stage 2 non-REM sleep using a three-tone auditory oddball paradigm. Stage 1 sleep was divided into trials preceded by alpha and those preceded by theta. A negative wave peaking at about 100 ms, N1, displayed a significant decrease in amplitude with the onset of Stage 2 sleep. A later N2 peaked at about 250 ms in the waking state. This changed into a sleep-specific negative wave peaking at 300 ms (N300) at the alpha-theta transition within Stage 1. The P300 displayed a similar shift to become a P450 in Stage 2 sleep. N550 was specific to Stage 2, and was larger in response to rare, rather than frequent stimuli. There was no evidence of any enhancement to relevant rare stimuli compared with irrelevant rare stimuli.
Aim of the present study was to assess changes in arousal rates after selective slow-wave (SWS) and total sleep deprivations.
Two-way mixed design comparing the arousal index (Al), as expressed by the number of EEG arousals divided by sleep duration, in totally or selectively sleep deprived subjects.
Sleep laboratory.
Nineteen normal male subjects [mean age=23.3 years (S.E.M.=0.55)].
Al was measured in baseline nights and after selective SWS (N=10) and total sleep deprivation (N=9).
During the baseline nights AI values changed across sleep stages as follows: stage 1 > stage 2 and REM > SWS, but did not present any significant variations as a function of time elapsed from sleep onset. The recovery after deprivation showed a reduction in EEG arousals, more pronounced after total sleep deprivation; this decrease affected NREM but not REM sleep. During the baseline nights Al showed a close-to-significance negative correlation with REM duration, while during the recovery nights a significant positive relation with stage 1 duration was found.
The present results suggest that recuperative processes after sleep deprivation are also associated with a higher sleep continuity as defined by the reduction of EEG arousals.
To determine whether sleep quality is influenced by the mode of mechanical ventilation, we performed polysomnography on 11 critically ill patients. Because pressure support predisposes to central apneas in healthy subjects, we examined whether the presence of a backup rate on assist-control ventilation would decrease apnea-related arousals and improve sleep quality. Sleep fragmentation, measured as the number of arousals and awakenings, was greater during pressure support than during assist-control ventilation: 79 +/- 7 versus 54 +/- 7 events per hour (p = 0.02). Central apneas occurred during pressure support in six patients; heart failure was more common in these six patients than in the five patients without apneas: 83 versus 20% (p = 0.04). Among patients with central apneas, adding dead space decreased sleep fragmentation: 44 +/- 6 versus 83 +/- 12 arousals and awakenings per hour (p = 0.02). Changes in sleep-wakefulness state caused greater changes in breath components and end-tidal CO2 during pressure support than during assist-control ventilation. In conclusion, inspiratory assistance from pressure support causes hypocapnia, which combined with the lack of a backup rate and wakefulness drive can lead to central apneas and sleep fragmentation, especially in patients with heart failure.
Recent studies have challenged the traditional hypothesis that excessive environmental noise is central to the etiology of sleep disruption in the intensive care unit (ICU). We characterized potentially disruptive ICU noise stimuli and patient-care activities and determined their relative contributions to sleep disruption. Furthermore, we studied the effect of noise in isolation by placing healthy subjects in the ICU in both normal and noise-reduced locations. Seven mechanically ventilated patients and six healthy subjects were studied by continuous 24-hour polysomnography with time-synchronized environmental monitoring. Sound elevations occurred 36.5 +/- 20.1 times per hour of sleep and were responsible for 20.9 +/- 11.3% of total arousals and awakenings. Patient-care activities occurred 7.8 +/- 4.2 times per hour of sleep and were responsible for 7.1 +/- 4.4% of total arousals and awakenings. Healthy subjects slept relatively well in the typically loud ICU environment and experienced a quantitative, but not qualitative, improvement in sleep in a noise-reduced, single-patient ICU room. Our data indicate that noise and patient-care activities account for less than 30% of arousals and awakenings and suggest that other elements of the critically ill patient's environment or treatment should be investigated in the pathogenesis of ICU sleep disruption.
BACKGROUND: Sleep deprivation may contribute to impaired immune function, ventilatory compromise, disrupted thermoregulation, and delirium. Noise levels in intensive care units may be related to disturbed sleep patterns, but noise reduction has not been tested in this setting. OBJECTIVE: To measure the effect of a noise reduction intervention on the sleep of healthy subjects exposed to simulated intensive care unit noise. METHODS: After digital audiotape recording of noise and development of the noise reduction intervention, 5 nocturnal 8-hour periods of sleep were measured in 6 paid, healthy volunteers at 7-day intervals in a sleep disorders center. Polysomnographic data were collected by experienced sleep disorders technicians and scored by certified raters. After the first 3 quiet nights, earplugs were randomly assigned to be worn on the fourth and fifth nights during exposure to the recorded noise. Sound pressure levels were measured during all 5 nights. RESULTS: Sleep architecture and sound measurements on quiet nights did not differ significantly. Sound levels were significantly lower on quiet nights than on noise nights. Exposure to the noise increased the number of awakenings, percentage of stage 2 sleep, and rapid eye movement latency and decreased time asleep, sleep maintenance efficiency index, and percentage of rapid eye movement sleep. Earplugs worn during exposure to the noise produced a significant decrease in rapid eye movement latency and an increase in the percentage of rapid eye movement sleep. CONCLUSION: The results provide a reasonable basis for testing the effects of earplugs on the sleep of critically ill subjects.
Sleep deprivation and fragmentation occurring in the hospital setting may have a negative impact on the respiratory system by decreasing respiratory muscle function and ventilatory response to CO2. Sleep deprivation in a patient with respiratory failure may, therefore, impair recovery and weaning from mechanical ventilation. We postulate that light, sound, and interruption levels in a weaning unit are major factors resulting in sleep disorders and possibly circadian rhythm disruption. As an initial test of this hypothesis, we sampled interruption levels and continuously monitored light and sound levels for a minimum of seven consecutive days in a medical ICU, a multiple bed respiratory care unit (RCU) room, a single-bed RCU room, and a private room. Light levels in all areas maintained a day-night rhythm, with peak levels dependent on window orientation and shading. Peak sound levels were extremely high in all areas representing values significantly higher than those recommended by the Environmental Protection Agency as acceptable for a hospital environment. The number of sound peaks greater than 80 decibels, which may result in sleep arousals, was especially high in the intensive and respiratory care areas, but did show a day-night rhythm in all settings. Patient interruptions tended to be erratic, leaving little time for condensed sleep. We conclude that the potential for environmentally induced sleep disruption is high in all areas, but especially high in the intensive and respiratory care areas where the negative consequences may be the most severe.
Strategies for treating hyperacusis, an anomolous condition of loudness perception, paradoxically seek either to minimize or enhance listeners' sound exposures.. We show that these reciprocal treatment approaches, implemented with similar amounts of background sound attenuation and enhancement, produce diametrically opposite perceptual effects in normal listeners. Specifically, we show after continuous, 2-week earplugging and low-level noise treatments that listeners become more and less sensitive, respectively, to the loudness of sounds. This simple demonstration of adaptive plasticity is consistent with modification of a theoretical gain control process, which is the basis for desensitizing sound therapies used in treating hyperacusis and related sound tolerance problems. (C) 2003 Acoustical Society of America.
This descriptive study using continuous polygraphic recording, observation and interview attempted to identify the quantity and quality of sleep and the factors which disturbed the sleep of selected patients in a respiratory intensive care unit. Documentation of behaviour which might be related to sleep deprivation and identification of factors which the patients perceived as interfering with rest and sleep were also recorded. It was concluded that patients had difficulty meeting their ‘normal’ needs for sleep due to frequent interruptions and possible sleep-disturbing factors. Behavioural changes related to sleep deprivation were observed.
Twelve patients aged 33--70 years (mean 49.5) underwent nightly recordings in the ICU and subsequently on the ward following acute myocardial infarction. Sleep patterns were analyzed according to night after infarct and ICU versus ward environment. Significant differences in nocturnal sleep patterns from matched controls initially after infarction included greater wakefulness, low REM sleep per cent, long REM latency, fewer REM periods, more awakenings, more stage shifts and decreased sleep efficiency. The usual circadian variation in HR was absent, and there was an estimated 8--10 h of unrecorded daytime sleep, which together suggested a quite generalized disruption of biological rhythms. With time, there was loss of daytime sleep, lowered nocturnal wakefulness and increased REM sleep. Slow-wave sleep (sometimes with very long duration delta waves) increased above normal over post-infarction nights 3--9, and sleep was otherwise renormalized by post-infarction night 9. No sudden sleep changes occurred with transfer from ICU to ward. The altered sleep patterns appeared mainly attributable to infarction itself. Twelve nocturnal anginal attacks occurred. Ten began in NREM sleep and two in REM periods without particularly intense phasic activity. Post-infarction nocturnal angina therefore appears to differ in pathogenesis from angina outside this period, which usually occurs in REM sleep. ECG changes could occur during sleep before awakening with pain, and overall decrease in ECG amplitude sometimes accompanied angina. Most attacks (10 of 12) occurred on post-infarction nights 4 and 5, indicating that undetermined that undetermined factors produce a secondary period of heightened risk at that time.
This study was designed to document quantitatively the sleep disturbances that occur after open heart surgery and to investigate a group of patients who underwent a thoracic surgical procedure not involving cardiopulmonary bypass. Nine patients were studied, six after open heart surgery and three after partial or complete pneumonectomy. In each patient, sleep patterns were recorded with use of all night polygraphy before and after operation and for up to 5 weeks on follow-up studies. After open heart surgery, patients manifested considerable suppression of both rapid eye movement and slow wave sleep patterns. In the three patients subjected to thoracotomy these sleep indexes returned to preoperative levels much earlier. Evidence of stage 2 sleep was present in one of the three patients with thoracotomy on the first postoperative night, and in two of the three both rapid eye movement and slow wave sleep returned to preoperative levels by the time of hospital discharge. It is concluded that patients undergoining open heart surgery experience both acute and chronic disruptions of sleep that last well beyond the hospital period of convalescence. These sleep disturbances have considerable relevance for postoperative management.
A brief discussion of human sleep is followed by presentation of data describing the variables that appear to affect human responsiveness to noise during sleep. Results from several studies that were conducted in different laboratories and that used several types of noises, age groups, and sexes are then combined to show that when EPNdB units are used as the measure of noise intensity, the correlation coefficient between intensity and the probability of no disturbance of sleep is −0.86. It is suggested also that a coefficient of similar magnitude would be obtained if units of EdBA were used. Some implications of these data are then exemplified.
Subject Classification: 50.70, 50.75.
This study examined the self-reported sleep patterns of adult patients undergoing coronary artery bypass graft (CABG) surgery and the relationship between their perceived illness-related stress and sleep disturbances. Twenty-four patients completed data at all three collection points: preadmission, and the third and sixth postoperative mornings. Patients responded to the Verran/Snyder-Halpern Sleep Scale and the Carr and Powers Stressor Scale for patients having CABG. By use of a within-subject, one-factor, repeated measures analysis of variance, statistically significant differences were found in each of the three sleep dimensions measured over time (disturbance, effectiveness, and supplementation). With the Pearson correlation, the hypothesis that sleep disturbances in patients having open-heart surgery are related to psychologic stress associated with illness was not supported. Additional analyses indicated that hospital and illness-related stress, duration of cardiopulmonary bypass, anesthesia time, and sleep medication were related to patients' sleep disturbance, effectiveness, or supplementation in different ways and at different times during the study periods.
Sleep was studied in nine patients for two to four days after major non-cardiac surgery by continuous polygraphic recording of electroencephalogram, electrooculogram, and electromyogram. Presumed optimal conditions for sleep were provided by a concerted effort by staff to offer constant pain relief and reduce environmental disturbance to a minimum. All patients were severely deprived of sleep compared with normal. The mean cumulative sleep time (stage 1 excluded) for the first two nights, daytime sleep included, was less than two hours a night. Stages 3 and 4 and rapid eye movement sleep were severely or completely suppressed. The sustained wakefulness could be attributed to pain and environmental disturbance to only minor degree. Sleep time as estimated by nursing staff was often grossly misjudged and consistently overestimated when compared with the parallel polygraphic recording. The grossly abnormal sleep pattern observed in these patients may suggest some fundamental disarrangement of the sleep-wake regulating mechanism.
The auditory awakening thresholds of the major electroencephalographically defined sleep stages were compared. A modification of the method of constant stimuli was used in an apparently successful attempt to minimize the incorporation of the experimental stimuli into the mental activity of the sleeper. A total of 319 experimental trials were distributed among seven human Ss who served for about six experimental nights each. The sequence and timing of experimental trials were counterbalanced to control for nights, habituation, amount of accumulated sleep, and amount of sleep since last awakening. The results showed approximately equal awakening thresholds during REM periods (the rapid eye movement stage of sleep) and stage 2 (low voltage EEG and 12 to 14 cps “sleep spindles”). Both these stages had lower awakening thresholds than delta sleep (large slow EEG waves). Awakening thresholds became lower with accumulated sleep, independent of sleep stage. There were no significant stage independent relationships between awakening threshold and time since last awakening or time since last body movement, although the latter were varied over a relatively narrow range which limits the generality of these findings. There was no stage independent relationship between heart rate and awakening threshold. The possible physiological determinants of the awakening response were discussed.
Auditory awakening thresholds ( AATs ) were assessed in sleeping men and women at three age levels (18 to 25, 40 to 48, and 52 to 71 years) with a procedure that employed a 5-sec tone in accordance with the up-and-down method. Although age was less influential than individual differences in predicting AAT levels, there was a significant and substantial AAT decline from early adulthood to later life in Sleep Stages 4, 2, and REM. With no variation by sex, this progressive decline was apparent by the 40s in Stages 4 and 2 and was sharpest from one age level to another in Stage 4. Decline was more gradual and delayed in REM, probably because of a sampling artifact based on stimulus incorporation in dreams. These findings help to explain increased sleep disturbance in the later years as a result of diminished intensity of sleep, which makes sleep more difficult to sustain.
This study was designed to examine the effect of sleep deprivation on a wide range of critically ill subjects while controlling the potential etiologic factors identified in earlier studies. The hypothesis that a positive correlation exists between sleep deprivation and the occurrence of the ICU syndrome was tested through data collection in 62 critically ill patients during their first 5 days in the ICU. This study documented mental status changes in 11% of the total sample and only 33% of those subjects with severe sleep deprivation showed an altered mental status on day 3. These percentages are lower than those documented in previous studies.
Normal spontaneous arousals from sleep are associated with transient increases in blood pressure, heart rate, and ventilation caused by large transient changes in autonomic output. These autonomic changes are out of proportion to obvious physiological need and are in excess of those observed in later periods of quiet wakefulness. This paper discusses some of the mechanisms underlying the cardio-respiratory consequences of arousal from sleep, and discusses why the normal onset of wakefulness may be associated with such large changes in autonomic output.
Our laboratory previously reported continuously monitored peak sound levels in several areas at Rhode Island Hospital. The number of sound peaks greater than 80 A-weighted decibels (dBA) was found to be high in the intensive and intermediate respiratory care unit (IRCU) areas, even at night. Environmental noise of this magnitude is potentially sleep-disruptive. Therefore, we hypothesized that nocturnal peak sound levels of > or = 80 dBA would be associated with an increase in EEG arousals from sleep in patients in the IRCU. Six patients underwent sleep monitoring while environmental peak sound levels were continuously recorded. Each 8-hour period (2200 to 0600 hours) was broken down into 30-minute segments. If there were 10 minutes or more of wakefulness in a segment, that segment was dropped from further analysis. Of the remaining 61 segments, there was a very strong correlation (r = 0.57, p = 0.0001) between the number of sound peaks of > or = 80 dBA and arousals from sleep. These 61 periods were then classified as quiet, moderately loud, and very loud based on the number of sound peaks (< or = 5, 6-15, and > 15, respectively). Analysis of variance revealed a significant difference between the number of arousals (p = 0.001) in quiet periods and that in very loud periods. We conclude that environmental noise may be an important cause of sleep disruption in the IRCU.
Noise levels in the hospital setting are exceedingly high, especially in the ICU environment. We set out to determine what caused the noises producing sound peaks > or = 80 A-weighted decibels (dBA) in our ICU settings, and attempted to reduce the number of sound peaks > or = 80 dBA through a behavior modification program.
The study was divided into two separate phases: noise identification and a trial of behavior modification. During the noise identification phase we simultaneously recorded sound peaks and the loudest noise heard subjectively by one observer in the medical ICU (MICU) and the respiratory ICU (RICU). During the behavior modification phase of the study we implemented a behavior modification program, geared toward noise reduction, in all of the MICU staff. Sound levels were monitored before and at the end of the behavior modification trial.
The MICU and RICU of a 720-bed teaching hospital in Providence, RI.
All ICU staff during the study period.
Once the noises that were determined to be amenable to behavior modification were identified, a behavior modification program was conducted during a 3-week period in our MICU. Baseline and post-behavior modification noise recordings were compared in 6-h intervals after sites were matched by number of patients in a room and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores.
We identified several causes of sound peaks > or = 80 dBA amenable to behavior modification; television and talking accounted for 49%. We also significantly reduced the 24-h mean peak noise level (p=0.0001), as well as the mean peak noise level (p=0.0001) and the number of sound peaks > or = 80 dBA (p=0.0001) in all 6-h blocks except for the 12 AM to 6 AM period.
We conclude that many of the noises causing sound peaks > or =80 dBA are amenable to behavior modification and that it is possible to reduce the noise levels in an ICU setting significantly through a program of behavior modification.
The etiology of sleep disruption in patients in intensive care units (ICUs) is poorly understood, but is thought to be related to environmental stimuli, especially noise. We sampled 203 patients (121 males and 82 females) from different ICUs (cardiac [CCU], cardiac stepdown [CICU], medical [MICU], and surgical [SICU]) by questionnaire on the day of their discharge from the unit, to determine the perceived effect of environmental stimuli on sleep disturbances in the ICU. Perceived ICU sleep quality was significantly poorer than baseline sleep at home (p = 0.0001). Perceived sleep quality and daytime sleepiness did not change over the course of the patients' stays in the ICU, nor were there any significant differences (p > 0.05) in these parameters among respective units. Disruption from human interventions and diagnostic testing were perceived to be as disruptive to sleep as was environmental noise. In general, patients in the MICU appeared to be more susceptible to sleep disruptions from environmental factors than patients in the other ICUs. Our data show that: (1) poor sleep quality and daytime sleepiness are problems common to all types of ICUs, and affect a broad spectrum of patients; and (2) the environmental etiologies of sleep disruption in the ICU are multifactorial.
Sleep deprivation may contribute to impaired immune function, ventilatory compromise, disrupted thermoregulation, and delirium. Noise levels in intensive care units may be related to disturbed sleep patterns, but noise reduction has not been tested in this setting.
To measure the effect of a noise reduction intervention on the sleep of healthy subjects exposed to simulated intensive care unit noise.
After digital audiotape recording of noise and development of the noise reduction intervention, 5 nocturnal 8-hour periods of sleep were measured in 6 paid, healthy volunteers at 7-day intervals in a sleep disorders center. Polysomnographic data were collected by experienced sleep disorders technicians and scored by certified raters. After the first 3 quiet nights, earplugs were randomly assigned to be worn on the fourth and fifth nights during exposure to the recorded noise. Sound pressure levels were measured during all 5 nights.
Sleep architecture and sound measurements on quiet nights did not differ significantly. Sound levels were significantly lower on quiet nights than on noise nights. Exposure to the noise increased the number of awakenings, percentage of stage 2 sleep, and rapid eye movement latency and decreased time asleep, sleep maintenance efficiency index, and percentage of rapid eye movement sleep. Earplugs worn during exposure to the noise produced a significant decrease in rapid eye movement latency and an increase in the percentage of rapid eye movement sleep.
The results provide a reasonable basis for testing the effects of earplugs on the sleep of critically ill subjects.
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Little is known about sleep/wake abnormalities in intensive care and less is known about the mechanisms responsible for these abnormalities. We studied 22 (20 mechanically ventilated) medical intensive care unit (ICU) patients with continuous polysomnography (PSG) and environmental noise measurements for 24-48 h to characterize sleep-wake patterns and objectively determine the effect of environmental noise on sleep disruption. All 22 patients demonstrated sleep-wake cycle abnormalities. There were large variations in total sleep time (TST) with the mean total sleep time per 24-h study period of 8.8 +/- 5.0 h. Sleep-wake cycles were fragmented and nonconsolidated with a mean of 57 +/- 18% and 43 +/- 18% of the TST occurring during the day and night, respectively. Environmental noise was responsible for 11.5 and 17% of the overall arousals and awakenings from sleep, respectively. The mean noise arousal index was 1.9 +/- 2.1 arousals/h sleep.
Conclusions:
(1) ICU patients are qualitatively, but not necessarily quantitatively, sleep deprived; and (2) although environmental noise is in part responsible for sleep-wake abnormalities, it is not responsible for the majority of the sleep fragmentation and may therefore not be as disruptive to sleep as the previous literature suggests.
Both the amplitude and latency of P300 vary with changes in stimulus parameters. Stimuli at intensities or pitch separations near threshold evoke a smaller and later P300. P300 is also affected by extraneous stimulus parameters in tasks where stimulus frequency separation is large and stimuli are well above intensity thresholds. For example, the presence of background white noise when tones are suprathreshold and easily detectable has been reported to increase P300 latency. However, the effects of background masking noise on P300 amplitude and scalp topography have not been reported. Subjects performed an oddball task both in the presence and in the absence of background noise. Performance accuracy was unaffected by background noise. P300 showed latency increases when noise was present, but P300 peak amplitude was unaffected. P300 scalp topography was stable across both conditions. P300 latency is affected by background noise, even when performance is not, but amplitude and amplitude topography remain unaffected.
Relationship between subjective and physiological assessments of noise disturbed sleep
- A Muzet
- Schieber
- Jp
- N Olivier-Martin
- Ehrhart
Muzet A, Schieber JP, Olivier-Martin N, Ehrhart J. Relationship between subjective and physiological assessments of noise disturbed sleep. Proc Int Congr, Noise Health Prob 1973;550:973–1008.
Sleep patterns after open heart surgery
- Orr
Orr W, Stahl M. Sleep patterns after open heart surgery. Am J Cardiol 1977;39:196–201.
EEG arousals: scoring rules and examples
Relationship between subjective and physiological assessments of noise disturbed sleep
- Muzet
Noise and sleep: a literature review and a proposed criterion fro assessing effect
- Lucas
The effect of background noise on P300 to suprathreshold stimuli
- Salisbury