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Effect on nurse and patient experience: Overnight use of blue-depleted illumination

December 2020
The Center For Health Design

Why does this study matter?
There are many factors that can support positive health outcomes in the hospital. Chief among these is getting quality sleep, but due to various issues such as pain, noise, and light – sleeping in the hospital is no easy task. Nighttime caregiving requires light, and care providers often have no choice but to use blue-spectrum overhead lights or flashlights to complete important caregiving tasks. These types of blue-wavelength lighting are disruptive to patients’ melatonin production – and melatonin depletion means interrupted sleep. And while there are some circadian lighting systems on the market, they are often costly and challenging to retrofit into existing healthcare facilities. Patients and staff stand to benefit from lighting that supports both of their needs, and can be easily integrated into existing spaces.

How was the study done?
Researchers worked with a lighting expert to develop a blue-depleted light pod that could be hung in the patient room near the headwall. The light was triggered by proximity to a wearable transmitter.

The study took place at a large urban medical center with 21 intermediate-acuity patients and 33 nurses. During the first two nights, nurses went about nighttime care tasks as usual, using standard patient room lights, flashlights, cellphone lights, or no lights at all. Then, for two additional nights, nurses relied on the blue-depleted light pods during nighttime activities. After the control period and again after the intervention period with the light pods, patients were surveyed on several sleep quality measures, satisfaction with their care experience, and their level of anxiety and depression. Estimates of sleep duration and latency were recorded during both periods. Nurses were surveyed about their perceptions of the devices.

So what do we learn from the study?
Nearly all nurses (94%) agreed that poor sleep affects patient outcomes, and the vast majority (80%) indicated that they would be interested in a better lighting solution. Nurses were generally satisfied with the pods, rating satisfaction at an average of eight out of ten, and most nurses (82%) felt that the lighting pods provided adequate light for nighttime care tasks (although they reported the lights were not bright enough for comfortable venipuncture).

Nurses went in to patient rooms four to eight times per night, and worked in almost complete darkness most of the time or half of the time. Survey results also showed 77% of nurses preferred the pods to other existing alternatives.

In terms of patient outcomes, the lighting intervention did not appear to have an effect on sleep duration, sleep latency, or how patients rated their quality of care at night. However, after two nights with the blue-depleted light pods, there was a statistically significant improvement (two-point reduction on a 21-point scale) in how patients rated their anxiety and depression.

Can we say the results are definitive?
Due to unpredictable patient length of stay, the researchers were not able to use a cross-over research design, putting patients into two separate groups to experience each lighting period in a swapped order. Cross-over design can be helpful to account for any effect that the order participants receive the intervention in a study. The authors acknowledge that introducing the light pod after the first two nights in the standard lighting scenario may have had a placebo effect. Further, as patients recover and begin to feel better, anxiety and depression may decrease, and so these improved scores could be attributed to improved clinical status and not necessarily to the lighting.

There are many reasons why it is difficult to sleep in the hospital. The combination of noise and pain are likely to affect sleep quality regardless of the lighting design. This study only focuses on lighting, but this is an important examination of one piece in a complex puzzle.

What’s the takeaway?
Blue-depleted light pods provided nurses with adequate lighting for most nighttime work in the patient room, and gave nurses a convenient alternative to bright-white short-wavelength overhead lighting or flashlights. Patient anxiety and depression scores were lower after two nights of the light pod intervention, compared to the period with standard lighting.

One of the most surprising findings from this study highlights the problem of nurses working in almost complete darkness in patient rooms to avoid disturbing patient sleep. And while blue-wavelength light is bad for patient sleep, no light is bad for everyone. Lighting design must support caregiving tasks and patient comfort without compromising safety.

It is also worth noting that this lighting pod is a cost-effective solution that can be introduced in healthcare settings without major renovations. The authors discuss the opportunity for future research to conduct a business case analysis and consider the cost of lighting compared to poor sleep related health outcomes such as delirium and falls. Sleep and safety are essential to patient recovery, so why not try better nightlights?

Albala, L., Bober, T., Hale, G., Warfield, B., Collins, M. L., Merritt, Z., Steimetz, E., Nadler, S., Lev, Y., & Hanifin, J. (2019). Effect on nurse and patient experience: Overnight use of blue-depleted illumination. BMJ Open Quality, 8(3), e000692. https://doi.org/10.1136/bmjoq-2019-000692


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