Journal article
Looking for light in the din: An examination of the circadian-disrupting properties of a medical intensive care unit
Intensive & critical care nursing, Vol.46, pp.57-63
06/2018
DOI: 10.1016/j.iccn.2017.12.006
PMID: 29605239
Abstract
Critically ill patients exhibit profound disturbances of circadian rhythmicity, most commonly in the form of a phase delay. We investigated the specific zeitgeber properties of a medical intensive care unit to develop a model that explained these abnormalities.
Prospective, observational study conducted during 2013–2014. Twenty-four-hour ambient light (lux, 672 hours) and sound pressure levels (dBA, 504 hours) were measured in patient rooms. Patients and families were surveyed regarding their perceptions of the environment.
University-based adult medical intensive care unit.
The timing and intensity of the ambient light-dark cycle and sound environment and the relationship of these measurements to patient/family perceptions.
Twenty-four-hour light-dark cycles were extremely weak and phase delayed relative to the solar cycle. Morning light averaged 12.1 (4.8, 37.2) lux, when only 24.9% ± 10.9% of available light was utilised; yet patients and families did not identify low daytime light levels as problematic. Median noise levels were invariably excessive (nighttime 47.9 [45.0, 51.3] dBA) with minimal variation, consistent with the absence of a defined rest period.
The intensive care unit functions as a near-constant routine protocol disconnected from solar time. Behavioural interventions to promote entrainment should be supported by objective measurements of light and sound.
Details
- Title: Subtitle
- Looking for light in the din: An examination of the circadian-disrupting properties of a medical intensive care unit
- Creators
- Samantha J Danielson - University of Iowa, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Occupational Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USACharles A Rappaport - University of Iowa, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Occupational Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USAMichael K Loher - University of Iowa, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Occupational Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USABrian K Gehlbach - University of Iowa, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Occupational Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USA
- Resource Type
- Journal article
- Publication Details
- Intensive & critical care nursing, Vol.46, pp.57-63
- DOI
- 10.1016/j.iccn.2017.12.006
- PMID
- 29605239
- NLM abbreviation
- Intensive Crit Care Nurs
- ISSN
- 0964-3397
- eISSN
- 1532-4036
- Publisher
- Elsevier Ltd
- Grant note
- DOI: 10.13039/100000050, name: National Heart, Lung, and Blood Institute, NIH, award: K23HL088020, T32 HL007638
- Language
- English
- Date published
- 06/2018
- Academic Unit
- Neurology; Pulmonary, Critical Care, and Occupational Medicine; Internal Medicine
- Record Identifier
- 9984020602302771
Metrics
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