Comparing average levels and peak occurrence of overnight sound in the medical intensive care unit on A-weighted and C-weighted decibel scales (original) (raw)
Related papers
Sleep Medicine, 2013
Objective: Uninterrupted sleep is of vital importance for restoration and regaining health. In intensive care units (ICUs) where recovering and healing is crucial, patients' sleep often is fragmented and disturbed due to noise from activities from oneself, other patients, and alarms. The aim of our study was to explore if sleep could be improved by modifying the sound environment in a way that is practically feasible in ICUs. Methods: We studied the effects of originally recorded ICU noise and peak reduced ICU noise on sleep in healthy male participants. Sleep was registered with polysomnography (PSG) during four nights: one adaptation night, one reference (REF) night, and the two exposed nights with similar equivalent sound levels (47 dB L Aeq ) but different maximum sound levels (56-vs 64-dB L AFmax ). The participants answered questionnaires and saliva cortisol was sampled in the morning. Results: During ICU exposure nights, sleep was more fragmented with less slow-wave sleep (SWS), more arousals, and more time awake. The effects of reduced maximum sound level were minor. The subjective data supported the polysomnographic findings, though cortisol levels were not significantly affected by the exposure conditions. Conclusions: Noise in ICUs impairs sleep and the reduction of maximal A-weighted levels from 64 to 56 dB is not enough to have a clear improved effect on sleep quality.
The nocturnal acoustical intensity of the intensive care environment: an observational study
Journal of Intensive Care, 2017
Background: The intensive care unit (ICU) environment exposes patients to noise levels that may result in substantial sleep disruption. There is a need to accurately describe the intensity pattern and source of noise in the ICU in order to develop effective sound abatement strategies. The objectives of this study were to determine nocturnal noise levels and their variability and the related sources of noise within an Australian tertiary ICU. Methods: An observational cross-sectional study was conducted in a 24-bed open-plan ICU. Sound levels were recorded overnight during three nights at 5-s epochs using Extech (SDL 600) sound monitors. Noise sources were concurrently logged by two research assistants. Results: The mean recorded ambient noise level in the ICU was 52.85 decibels (dB) (standard deviation (SD) 5.89), with a maximum noise recording at 98.3 dB (A). All recorded measurements exceeded the WHO recommendations. Noise variability per minute ranged from 9.9 to 44 dB (A), with peak noise levels >70 dB (A) occurring 10 times/hour (SD 11.4). Staff were identified as the most common source accounting for 35% of all noise. Mean noise levels in single-patient rooms compared with open-bed areas were 53.5 vs 53 dB (p = 0.37), respectively. Conclusion: Mean noise levels exceeded those recommended by the WHO resulting in an acoustical intensity of 193 times greater than the recommended and demonstrated a high degree of unpredictable variability, with the primary noise sources coming from staff conversations. The lack of protective effects of single rooms and the contributing effects that staffs have on noise levels are important factors when considering sound abatement strategies.
Improvement of ICU sound environment and analyses of consequences on sleep - an experimental study
Objective: Uninterrupted sleep is of vital importance for restoration and regaining health. In intensive care units (ICU) where recovering and healing is crucial, patients’ sleep is often fragmented and disturbed due to noise from activities from personal, other patients and alarms. The aim of this study was to explore if sleep could be improved by modifying the sound environment in a way that is practically feasible in an ICU. Methods: The effects of originally recorded ICU noise and peak reduced ICU noise on sleep in healthy male subjects was studied. Sleep was registered with polysomnography (PSG) during four nights: one adaptation night, one reference night and the two exposed nights with similar equivalent sound levels (47 dB LAeq) but different maximum sound levels (56 vs 64dB LAFmax). The subjects answered questionnaires and saliva cortisol were sampled in the morning. Results: During ICU exposure nights, sleep was more fragmented with less slow wave sleep, more arousals and ...
Critical Care, 2009
Excessive noise is becoming a significant problem for intensive care units (ICUs). This paper first reviews the impact of noise on patients' sleep in ICUs. Five previous studies have demonstrated such impacts, whereas six other studies have shown other factors to be more important. Staff conversation and alarms are generally regarded as the most disturbing noises for patients' sleep in ICUs. Most research in this area has focused purely on noise level, but work has been very limited on the relationships between sleep quality and other acoustic parameters, including spectrum and reverberation time. Sound-absorbing treatment is a relatively effective noise reduction strategy, whereas sound masking appears to be the most effective technique for improving sleep. For future research, there should be close collaboration between medical researchers and acousticians. ICU = intensive care unit; IL = interleukin; NREM, non-rapid eye movement; REM = rapid eye movement; RT = reverberation time.
Noise levels in a general intensive care unit: a descriptive study
Nursing in Critical Care, 2007
The aim of this small-scale study was to measure, analyse and compare levels of acoustic noise, in a nine-bedded general intensive care unit (ICU). Measurements were undertaken using the Norsonic 116 sound level meter recording noise levels in the internationally agreed 'A' weighted scale. Noise level data were obtained and recorded at 5 min over 3 consecutive days. Results of noise level analysis indicated that mean noise levels within this clinical area was 56Á42 dB(A), with acute spikes reaching 80 dB(A). The quietest noise level attained was that of 50 dB(A) during sporadic intervals throughout the 24-h period. Parametric testing using analysis of variance found a positive relationship (p 0Á001) between the nursing shifts and the day of the week. However, Scheffe multiple range testing showed significant differences between the morning shift, and the afternoon and night shifts combined (p 0Á05). There was no statistical difference between the afternoon and night shifts (p ! 0Á05). While the results of this study may seem self-evident in many respects, what it has highlighted is that the problem of excessive noise exposure within the ICU continues to go unabated. More concerning is that the prolonged effects of excessive noise exposure on patients and staff alike can have deleterious effect on the health and well-being of these individuals.
Analysis of relationships between the sound environment at the ICU and intensive care delirium
High sound levels related to medical equipment and high activity day and night, is a wellknown phenomenon in intensive care units (ICUs). This may result in poor sleep and prolonged recovery for the patients but may also be a precipitating factor for intensive care delirium (ICU delirium).The aim of this pilot study was to describe patients' responses to the sound environment in an ICU and to identify patients' early signs of ICU delirium. Twenty patients from a general Swedish ICU were invited to participate in the project. Data from patients' records and observation protocols were collected and interviews with the patients were made after discharge from the ICU. Data were analysed by using both qualitative and quantitative content analysis. Findings from the analysis of sound registrations, documents and patients' interviews will be reported.
Intensive and Critical Care Nursing, 2012
This study had two aims: first to describe, using both descriptive statistics and quantitative content analysis, the noise environment in an ICU patient room over one day, a patient's physical status during the same day and early signs of ICU delirium; second, to describe, using qualitative content analysis, patients' recall of the noise environment in the ICU patient room. The final study group comprised 13 patients. General patient health status data, ICU delirium observations and sound-level data were collected for each patient over a 24hour period. Finally, interviews were conducted following discharge from the ICU. The sound levels in the patient room were higher than desirable and the LAF max levels exceed 55 dB 70-90% of the time. Most patients remembered some sounds from their stay in the ICU and whilst many were aware of the sounds they were not disturbing to them. However, some also experienced feelings of fear related to sounds emanating from treatments and investigations of the patient beside them. In this small sample, no statistical connection between early signs of ICU delirium and high sound levels was seen, but more research will be needed to clarify whether or not a correlation does exist between these two factors.
Noise in the Intensive Care Unit (Icu)
2007
A comprehensive literature review of noise levels in the hospital intensive care unit (ICU) revealed that noise is a problem in the ICU. Numerous studies conducted in overseas hospitals consistently found that the noise levels exceeded recommended levels. Patients in the ICU are in a critical condition. Noise can prevent a person from sleeping and can be offensive. Sleep deprived patients may experience slow tissue growth and depression coupled by the strain of being in a serious state of health. A study was conducted that involved a noise level analysis of a prominent Australian hospital’s ICU. It found that the noise levels exceeded the maximum recommended design sound level prescribed by Standards Australia Investigation into the cause of the high noise levels revealed a number of sources. Recommendations were made to reduce noise levels in the ICU and design features were suggested that could reduce sound exposure to the patients.
Evaluating the Noise level at Qazvin University Hospital’s Intensive Care Units
Biotechnology and Health Sciences, 2015
Background: Noise at Intensive Care Units (ICU) has an adverse effect on patients and ICU staff. There are some evidences that sleep, recovery from critical illness and average background noise in hospitals as recommended by the US Environmental Protection Agency (EPA) and World Health Organization (WHO) should not exceed 30 A-weighted decibel (dBA) and peaks during night time should be less than 40 dBA. This survey was conducted to measure noise levels and their relationship with the time of the day and location in the ICU. Objectives: The objectives of this study were to measure noise levels and evaluate their relationship with time of day and location in the ICU. Materials and Methods: This cross sectional study was conducted in a public university hospital, namely Qazvin University of Medical Sciences, Qazvin, Iran. Noise levels were measured with SLM Sound level meter (model: Tes-1443) during 24 hours with the equivalent sound level (LEQ), maximum (Max) and peak sound pressure based on the ISO 9612.this tool can measure in the range of 30 to 110 dB dynamic network. While frequency A, fast time scale networks with 125 ms fast response microphones were selected. This method says that measuring point must have distance 1.5 meter from the wall at a height of 1.25 m above ground level. At the bedside of patients measurement done by 3 TES model 1353 H Tool by a Taiwanese company. Results: This survey showed that the Equivalent Sound Level (Leq) in ICU was much higher than the standard level. The Maximum Sound Level (Lmax) in most places was 84-89 dBA and just in one measurement in the Internal ICU reached 90 dB. The average level of Leq in ICU was 70 dB. Conclusions: Equivalent noise level and Noise Criteria in ward remarkably exceeds the standards levels. This condition will be produce Dangerous circumstances for admitted patients in ward.
Noise and Sleep Among Adult Medical Inpatients: Far From a Quiet Night
Archives of Internal Medicine, 2012
Despite the importance of sleep for recovery, hospital noise may put patients at risk for sleep loss and its associated negative effects. Objectively measured hospital noise can range as high as 67 dB in the intensive care unit to 42 dB in surgical wards, far from the World Health Organization (WHO) international recommendations of 30 dB for patient rooms. 1 Although almost half of Medicare patients report that their hospital rooms were not quiet at night, data to objectively characterize noise levels and sleep in hospitalized adults in medical wards are limited. 2 One study that objectively measured sleep and noise among hospitalized adults older than 70 years found no association. 3 This study aimed to objectively measure noise and sleep duration in adult medical ward patients. Methods Eligible patients were community-dwelling ambulatory adults older than 50 years who were not transferred from the intensive care unit and enrolled in an ongoing study of general medicine inpatients at the University of Chicago Medical Center. 4 Patients with a known sleep disorder (ie, obstructive sleep apnea), with cognitive impairment (score of <17 on a telephone version of the Mini-Mental State Examination), under respiratory isolation, or admitted for more than 72 hours were excluded. The study was approved by the University of Chicago institutional review board.