Sounds of Sleep (08-05-10)

Solet and her team have investigated the noise levels that can be experienced by hospital patients during the night.  Their “results provide evidence that repeated arousals occur from common hospital noises at typical decibel levels even in healthy young adults.  The reported responses varied with the sound stimulus characteristics and across different sleep stages.”  Although their data were collected in a sleep laboratory, the researchers were careful to recreate the sound levels and types experienced by hospital patients by using recordings of noises made in hospitals.  This project is noteworthy because it carefully quantifies the sleep disrupting capabilities of nighttime hospital noises. 

Specifically, researchers found “Phone and intravenous infusion pump alarms, which are intentionally designed to be alerting, were effective in evoking the highest arousal probabilities. “  Conversations among staff members were also found to impede sleep. 

The research team make the common sense suggestion to reduce background noise levels in hospitals, from HVAC systems, for example, and then lower the volume of pump alarms, lower the ring volumes on patient room phones and reduce the number of rings sounded for any one telephone call.  Surface materials and other tools to limit sound transmission from nurses’ stations are also suggested.  In addition “Special consulting spaces should be allocated for nurses in which voice-based information can be transferred away from open hall areas, yet not far from nursing stations. Protocols such as dimming hall lights at night as a “quiet cue” should be incorporated as part of behavioral protocols to limit sleep disruption by staff voices.”  Finally, “Proper door hardware will limit latch noises; door gasket selection will better protect patients from hall and nurses’ station noise, as well as blocking transfer out of noise generated within that patient room.  Policy regarding keeping patient doors open should be re examined. Other options should be considered, including systems-level solutions such as telemetry to a common station and assignment of staff to specific patients, allowing them to be individually alerted to patient needs.” 

Solet and her colleagues report “A quieter environment is also more protective of staff, reducing stress and burnout, enhancing communication, and reducing medical errors—all of which contribute to higher quality healthcare. “

Specific details regarding the sounds types and levels tested are available in the complimentary report at the website noted below.

Jo Solet, Orfeu Buxton, Jeffrey Ellenbogen, Wei Wang, and Andrew Carballeira.  2010.  “Evidence-Based Design Meets Evidence-Based Medicine:  The Sound Sleep Study.”  Center for Health Design, http://www.healthdesign.org