Environmental noise levels in hospital settings: A rapid review of measurement techniques and implementation in hospital settings

Relationship between noise levels and intensive care patients' clinical complexity: An observational simulation study

BACKGROUND

Noise pollution in intensive care units is a relevant problem, associated with psychological and physiological consequences for patients and healthcare staff. Sources of noise pollution include medical equipment, alarms, communication tools, staff activities, and conversations.

AIMS

To explore the cumulative effects of noise caused by an increasing number and type of medical devices in an intensive care setting on simulated patients with increasing clinical complexity. Secondly, to measure medical device alarms and nursing activities' sound levels, evaluating their role as potentially disruptive noises.

STUDY DESIGN

Observational simulation study (reported according to the STROBE checklist). Using an electronic sound meter, the sound levels of an intensive care room in seven simulated clinical scenarios were measured on a single day (09 March 2022), each featuring increasing numbers of devices, hypothetically corresponding to augmented patients' clinical complexity. Secondly, noise levels of medical device alarms and specific nursing activities performed at a distance of three meters from the sound meter were analysed.

RESULTS

The empty room's mean baseline noise level was 37.8 (±0.7) dBA; among the simulated scenarios, noise ranged between 45.3 (±1.0) and 53.5 (±1.5) dBA. Alarms ranged between 76.4 and 81.3 dBA, while nursing tasks (closing a drawer, opening a saline bag overwrap, or sterile packages) and speaking were all over 80 dBA. The noisiest activity was opening a sterile package (98 dBA).

CONCLUSION

An increased number of medical devices, an expression of patients' higher clinical complexity, is not a significant cause of increased noise. Some specific nursing activities and conversations produce higher noise levels than medical devices and alarms. This study's findings suggest further research to assess the relationships between these factors and to encourage adequate noise reduction strategies.

RELEVANCE TO CLINICAL PRACTICE

Excessive noise level in the intensive care unit is a clinical issue that negatively affects patients' and healthcare providers' well-being. The increase in baseline room noise from medical devices is generally limited. Typical nursing tasks and conversations produce higher noise levels than medical devices and alarms. These findings could be helpful to raise awareness among healthcare professionals to recognize noise sources. The noisiest components of the environment can be modified by staff behaviour, promoting noise reduction strategies and improving the critical care environment.

Characterization of sound pressure levels and sound sources in the intensive care unit: a 1 week observational study

Background

Exposure to elevated sound pressure levels within the intensive care unit is known to negatively affect patient and staff health. In the past, interventions to address this problem have been unsuccessful as there is no conclusive evidence on the severity of each sound source and their role on the overall sound pressure levels. Therefore, the goal of the study was to perform a continuous 1 week recording to characterize the sound pressure levels and identify negative sound sources in this setting.

Methods

In this prospective, systematic, and quantitative observational study, the sound pressure levels and sound sources were continuously recorded in a mixed medical-surgical intensive care unit over 1 week. Measurements were conducted using four sound level meters and a human observer present in the room noting all sound sources arising from two beds.

Results

The mean 8 h sound pressure level was significantly higher during the day (52.01 ± 1.75 dBA) and evening (50.92 ± 1.66 dBA) shifts than during the night shift (47.57 ± 2.23; F(2, 19) = 11.80, p < 0.001). No significant difference was found in the maximum and minimum mean 8 h sound pressure levels between the work shifts. However, there was a significant difference between the two beds in the based on location during the day (F(3, 28) = 3.91, p = 0.0189) and evening (F(3, 24) = 5.66, p = 0.00445) shifts. Cleaning of the patient area, admission and discharge activities, and renal interventions (e.g., dialysis) contributed the most to the overall sound pressure levels, with staff talking occurring most frequently.

Conclusion

Our study was able to identify that continuous maintenance of the patient area, patient admission and discharge, and renal interventions were responsible for the greatest contribution to the sound pressure levels. Moreover, while staff talking was not found to significantly contribute to the sound pressure levels, it was found to be the most frequently occurring activity which may indirectly influence patient wellbeing. Overall, identifying these sound sources can have a meaningful impact on patients and staff by identifying targets for future interventions, thus leading to a healthier environment.

Sleep disruption and delirium in critically ill children: Study protocol feasibility

Delirium is a serious complication of pediatric critical illness. Sleep disruption is frequently observed in children with delirium, and circadian rhythm dysregulation is one proposed cause of delirium. Children admitted to the pediatric intensive care unit (PICU) experience multiple environmental exposures with the potential to disrupt sleep. Although researchers have measured PICU light and sound exposure, sleep, and delirium, these variables have not yet been fully explored in a single study. Furthermore, caregiving patterns have not often been included as a component of the PICU environment. Measuring the light and sound exposure, caregiving patterns, and sleep of critically ill children requires continuous PICU bedside data collection. This presents multiple methodological challenges. In this paper, we describe the protocol for an observational pilot study of the PICU environment, sleep, and delirium experienced by a sample of 10 critically ill children 1-4 years of age. We also evaluate and discuss the feasibility (i.e., acceptability, implementation, practicality) of the study protocol. Light and sound exposure were measured with bedside sensors. Caregiving was quantified through video recording. Sleep was measured via actigraphy and confirmed by video recording. Delirium screening with the Cornell Assessment of Pediatric Delirium was conducted twice daily, either in person or via video review. This study provides a refined measurement framework to inform future, large-scale studies and the development of nurse-driven sleep promotion interventions.

Methods for Measuring and Identifying Sounds in the Intensive Care Unit

Background

Despite many studies in the field examining excessive noise in the intensive care unit, this issue remains an ongoing problem. A limiting factor in the progress of the field is the inability to draw conclusions across studies due to the different and poorly reported approaches used. Therefore, the first goal is to present a method for the general measurement of sound pressure levels and sound sources, with precise details and reasoning, such that future studies can use these procedures as a guideline. The two procedures used in the general method will outline how to record sound pressure levels and sound sources, using sound level meters and observers, respectively. The second goal is to present the data collected using the applied method to show the feasibility of the general method and provide results for future reference.

Methods

The general method proposes the use of two different procedures for measuring sound pressure levels and sound sources in the intensive care unit. The applied method uses the general method to collect data recorded over 24-h, examining two beds in a four-bed room, via four sound level meters and four observers each working one at a time.

Results

The interrater reliability of the different categories was found to have an estimate of >0.75 representing good and excellent estimates, for 19 and 16 of the 24 categories, for the two beds examined. The equivalent sound pressure levels (L_Aeq) for the day, evening, and night shift, as an average of the sound level meters in the patient room, were 54.12, 53.37, and 49.05 dBA. In the 24-h measurement period, talking and human generated sounds occurred for a total of 495 (39.29% of the time) and 470 min (37.30% of the time), at the two beds of interest, respectively.

Conclusion

A general method was described detailing two independent procedures for measuring sound pressure levels and sound sources in the ICU. In a continuous data recording over 24 h, the feasibility of the proposed general method was confirmed. Moreover, good and excellent interrater reliability was achieved in most categories, making them suitable for future studies.

Noise Pollution in Intensive Care Unit: A Hidden Enemy affecting the Physical and Mental Health of Patients and Caregivers

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.

Environmental noise in hospitals: a systematic review

Environmental noise has been growing in recent years, causing numerous health problems. Highly sensitive environments such as hospitals deserve special attention, since noise can aggravate patients' health issues and impair the performance of healthcare professionals. This work consists of a systematic review of scientific articles describing environmental noise measurements taken in hospitals between the years 2015 and 2020. The researchers started with a consultation of three databases, namely, Scopus, Web of Science, and ScienceDirect. The results indicate that for the most part, these studies are published in journals in the fields of medicine, engineering, environmental sciences, acoustics, and nursing and that most of their authors work in the fields of architecture, engineering, medicine, and nursing. These studies, which are concentrated in Europe, the Americas, and Asia, use as reference values sound levels recommended by the World Health Organization. L_eq measured in hospital environments showed daytime values ranging from 37 to 88.6 dB (A) and nighttime values of 38.7 to 68.8 dB (A). L_eq values for outdoor noise were 74.3 and 56.6 dB (A) for daytime and nighttime, respectively. The measurements were taken mainly inside hospitals, prioritizing more sensitive departments such as intensive care units. There is a potential for growth in work carried out in this area, but research should also include discussions about guidelines for improvement measures aimed at reducing noise in hospitals.