Patients in Intensive Care Units (ICUs) are nearly always under a great deal of physical and mental stress. The reason they are in the unit is because they have a life-threatening condition, and the unfamiliar surroundings and intensive treatment regimes they are subjected to add to their stress levels. As a result, a significant number of patients lapse into a state of delirium. By controlling the environment in ways that relieve patient stress, the Philips ‘Clear Mind’ project aims to reduce the incidence of ICU delirium and its consequences.
Delirium is a serious problem in ICUs, with patients becoming confused, not knowing where they are, or not recognizing close family members. In some cases, it will cause patients to become hyperactive (for example, trying to get out of bed or disconnecting monitoring equipment or drips). In other cases they will exhibit hypoactivity, becoming very drowsy or withdrawn. Because the symptoms of delirium can easily be confused with those of other disorders such as dementia or depression, it takes a skilled nurse or doctor to recognize delirium and counter it. However, doing so is extremely important, because research has shown that patients who suffer from delirium are twice as likely to die in the ICU and three times more likely to die in the following six months, compared to patients who do not suffer it. Delirium also has high associated healthcare costs, increasing ICU costs by 30% to 60% due to increased lengths of stay in the ICU. In the USA alone, the annual cost of ICU-related delirium is estimated at US$145 billion - more than 1.5 times that associated with the country’s diabetes epidemic. Prevention of delirium and better ways of detecting it when it does occur are therefore important clinical needs.
Causes of delirium
There are many different causes of delirium but in general they can be divided into two categories. The first of these comprises clinical factors such as inadequate pain relief, trauma, medication, metabolic disturbance and toxin accumulation, several of which directly affect the patient’s brain chemistry. The second category comprises environmental factors such as disconnection from familiar surroundings and friends and family; sleep disturbance due to monitoring system alarms or frequent nursing interventions (for example, routine observations or drug administration); and circadian rhythm disturbance due to continuous room lighting or a lack of connection to the outside world. Many of these causal factors are commonplace in ICU environments, and some are an inevitable consequence of clinical care. However, there is a real need to find ways of minimizing their impact in order to reduce an experience that often leaves long lasting mental scars on patients and worsens their prognosis.
The Philips ‘Clear Mind’ project
The Philips ‘Clear Mind’ project aims to reduce the incidence of delirium in ICUs by controlling environmental factors that contribute to its onset, and by providing feedback to nursing staff so that they can adapt their pattern of care to each individual patient.
Since there is an increasing amount of evidence that noise within ICUs is a major contributor to patient disturbance and confusion, one area of research in the Clear Mind project focuses on reducing the negative effects of ambient noises, such as conversations and monitoring alarms. By analyzing the soundscape in a representative ICU room over a number of days, the researchers were able to build a computer model that categorizes different types of sound, such as speech, alarms, dropped objects etc. and predicts their disturbance rating. The proposed ‘healing environment’ prototype being developed by Philips Research will use this computer model to generate a visual indication of each room’s sound quality in terms of its likely contribution to delirium, potentially helping doctors and nurses to be more vigilant and noise-conscious when they deal with particular patients.
Future research work will focus on actively reducing the impact of unwanted noise sources, such as air-conditioning system noise, using noise cancellation or noise masking techniques. The speakers required by these techniques could also be used to deliver positive sounds, such as the patient’s favorite music tracks, which could help to orientate patients and reduce their anxiety levels.
In addition to controlling soundscapes in order to reduce the likelihood of delirium, the Clear Mind project is also investigating the use of video monitoring to implement continuous delirium detection. The captured video will be analyzed for disturbed body movement patterns that could be indicative of delirium. These could include increased motor activity and restlessness in hyperactive delirium patients, and decreased motor activity and speed of movement in hypoactive delirium patients.
Other research aspects in the Clear Mind project are environmental factors such as lighting, air quality and temperature and ways in which these factors can be controlled in order to help preventing delirium.
+ Philips opens Hospital Research Area to develop innovative healing environments (press release)
Adaptive Healing Room