Fiona Stanley Hospital is working with Edith Cowan University to improve acoustic design with the aim of reducing noise levels in intensive care units (ICUs).
Research suggests that around half of intensive care patients experience sleep disturbances due to noise, which can hinder recovery and negatively impact their health.
As part of the project, ECU Adjunct Senior Research Fellow Dr. Emil Jonescu and the head of intensive care research at Fiona Stanley Hospital, Professor Ed Litton, conducted a research study in a 40-bed intensive care unit at Fiona Stanley Hospital in Perth. Clinicians, doctors, academics and industry consultants were involved in the study.
It examined the effects of noise on patient sleep quality and physician performance and provides practical recommendations for design approaches to noise reduction.
Analysis of room acoustics showed that the maximum noise level in the intensive care unit was at times between 60 and 90 dB(A), exceeding the threshold values for sleep disorders set by the World Health Organization guidelines.
Beeps and alarms
Jonescu said noise was caused primarily by alarms from medical equipment and discussions among clinical staff and was a common problem in all intensive care units.
“In the intensive care unit, there are a lot of beeps and alarms from machines, and some of these noises cannot be mitigated because of the important information provided to doctors,” he said.
“Our goal was to find the optimal balance between good information flow for clinicians and rest and recovery for patients, and we found that some design improvements can certainly be made.”
Professor Litton said sleep problems were a major issue raised by patients in intensive care and that sleep problems could often persist after discharge, which could cause stress and impede recovery.
“It’s very important to think holistically about how we can make the ICU experience as comfortable as possible for patients,” he said.
“That means we need to collaborate widely, including with design experts, to address the issues that matter to our patients.”
Employee perceptions
Part of the study examined healthcare professionals’ perceptions of the impact of noise on patients’ sleep and ICU staff’s tasks.
Staff reported that ICU noise negatively impacted work performance, patient retention, and job satisfaction.
“They stated that their biggest concern was the impact on patients’ sleep quality; “But they also believe that a quieter ICU would improve doctors’ ability to think,” Jonescu said.
“ICU physicians and patients share the same environment and it is clear that improving noise levels benefits everyone.”
Noise between rooms
Through a 3D modeling process, the researchers simulated various acoustic treatment improvements.
They found that the room layout and furnishings precluded many noise reduction options. These were limited to sound absorption on the external surface, while direct transmission paths and volume settings offered potential for more significant noise reduction.
“One of the key findings of the study was that by focusing on noise reduction strategies for the partitions between patient rooms, the transmission of noise from room to room can be significantly reduced,” Jonescu said.
“The results showed a significant reduction of 14 decibels when doors between rooms were open.”
Further research
Jonescu said the study showed potential for medical device designers to consider the directivity of alarm speakers, which could focus sound onto sound-absorbing wall surfaces and reduce noise exposure for patients.
“Future research could also examine the minimum volume at which machines can operate without affecting doctors’ ability to do their jobs,” he said.
“Reducing the volume from the default maximum of 100% could have a massive impact on reducing overall noise and would cost nothing.”
The study, “Mitigating Intensive Care Unit Noise: Design-Led Modeling Solutions, Calculated Acoustic Outcomes, and Cost Implications,” was published in HERD: Health Environments Research & Digital Design Journal.