The circadian rhythm of patients in intensive care is often disrupted by heavy medication or anaesthesia. With the assistance of lighting, the research team hope to help patients find a faster means of achieving a good balance between sleep and wakefulness.
The four year research project is led by Berit Lindahl, Senior Lecturer at the School of Health Sciences at the University of Borås.
A room with indirect light
“In the hospital’s intensive care unit we have designed a test room; a calm environment equipped with indirect light that mirrors the pattern of daylight in regards to colour temperature and intensity.
An approach, we hope, will help patients maintain their circadian rhythm. We also hope that this ”circadian lighting solution” will help limit the occurrence of postoperative delirium, the use of painkillers and, in an ideal world, shorten the length of stay.
Due to the design of the lighting solution, the staff had to make some concessions in terms of light levels during the night. We use lower light levels than normal in order not to stimulate cortisol production but, of course, without compromising patient safety,” says Berit Lindahl.
In addition to supplying the luminaires for the test project, Fagerhults Head of Research, Tommy Govén, worked with Torbjörn Laike at Lund University to provide the industry expertise.
”The lighting imitates daylight. In the early morning the light is more intense and cold, then slightly reduced for the rest of the morning. Between 11 am and 1 pm the light is dimmed down to a warmer colour temperature and lower light levels. The intensity of light and colour temperature is reduced gradually in the late afternoon to make the patient ready to face the night,” says Tommy Govén.
Avoid high and stressful light levels during night. — Tommy Govén, Research Director, Fagerhult
Adjustable colour temperature
The luminaires are equipped with ”tuneable white”, which enables the colour temperature to be adjusted from 2700 Kelvin to 6500 Kelvin, or from warm to cold light. The intensity can also be controlled from 0 lux to 1,000 lux.
”The light is mainly ambient, i.e. directed to walls and ceilings. The idea is that we will help the body to get started with the production of the stress hormone cortisol. The production of melatonin, which controls our sleep, is more difficult to influence. Therefore, it is important to avoid high and stressful light levels at night as much as possible.”