Education, Research, and Quality Improvement |

Sources of Overnight Patient Sleep Disruption in the Medical Intensive Care Unit FREE TO VIEW

Melissa Knauert*, PhD; H. Klar Yaggi, MD; Nancy Redeker, PhD; Terrence Murphy, PhD; Katy Araujo, MPH; Margaret Pisani, MD
Author and Funding Information

Yale University School of Medicine, New Haven, CT

Chest. 2012;142(4_MeetingAbstracts):547A. doi:10.1378/chest.1383037
Text Size: A A A
Published online


SESSION TYPE: Outcomes/Quality Control Posters

PRESENTED ON: Wednesday, October 24, 2012 at 01:30 PM - 02:30 PM

PURPOSE: Environment likely plays a key role in the severe sleep disruption of medical intensive care unit (MICU) patients. Limited studies link patient arousals with noise and noise peaks. Studies of overnight ICU activity reveal frequent in-room interruptions; one study, using patient questionnaires, demonstrated that phlebotomy was a leading source of disruption. World Health Organization (WHO) guidelines for background noise in patient rooms are 35 decibels (dB) during the day and 30 dB during the night. Our study seeks to characterize overnight sound levels and in-room activity for MICU patients.

METHODS: We reviewed 70 MICU patient charts and recorded in-room activities between midnight and 4:00 AM. Based on this chart review and via direct observation, we identified the key elements of nocturnal patient disruption. We utilized the Extech HD600 sound level meter to measure sound in MICU patient rooms between midnight and 4:00 AM.

RESULTS: We established an overnight (midnight to 4:00 AM) in-room activity mean of 16.9 ± 0.9 standard error (SE). Vital sign recording, patient positioning and nurse patient assessment (RASS and pain) were the most common activities. Sound meter monitoring revealed a C-weighted (C) mean noise level of 60.33 dB ± SE of 0.01 dB between the hours of midnight and 4:00 AM; sound level maximums exceeded 83 dB(C) every hour between midnight and 4:00 AM in every room monitored. There were not significant differences between rooms with and without mechanical ventilation.

CONCLUSIONS: Baseline measurements of sound and in-room activity identify significant sources of nocturnal disturbance. The mean sound level is profoundly in excess of levels recommend by the WHO. A significant portion of these disturbances are not time critical and could be avoided during a designated overnight low disturbance period.

CLINICAL IMPLICATIONS: Sleep disruption in the MICU is prevalent and may be linked to delirium and immune dysfunction. Sleep deprived patients are thus at risk for worse MICU outcomes. This study is a first step in identifying and eliminating avoidable sources of MICU patient disturbance.

DISCLOSURE: The following authors have nothing to disclose: Melissa Knauert, H. Klar Yaggi, Nancy Redeker, Terrence Murphy, Katy Araujo, Margaret Pisani

No Product/Research Disclosure Information

Yale University School of Medicine, New Haven, CT




Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543