Delirium at the Intensive Care Unit - a Retrospective Cohort Study

Study Overview
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Brief Summary
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This project seeks to describe the incidence of delirium in the Intensive Care Unit (ICU) and to identify risk and preventive factors associated with development of delirium. Especially, the investigators want to investigate if an imitated natural light/dark cycle influences frequency of delirium.

Detailed Description
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A common problem for patients in the ICU is episodes of delirium. Recent trials have described incidences ranging from 60-87% of patients in a number of different countries. Delirium is a condition with fluctuating conscience, disorganized thinking and disturbance of the sleep/wake cycle. Many patients with delirium experience hallucinations and agitation which can be very unpleasant for both patients and their families. Some risk factors for the development of delirium well known, e.g. dementia, hypertension, illness severity (SAPS II score), delirium on the previous day, mechanical ventilation, emergency surgery and metabolic acidosis. The effect of sedative drug administration is not clear, as studies has been inconclusive. Even though studies regarding the impact of sleep deprivation on development of delirium have been inconclusive, there is no doubt that delirious patients have a disturbed sleep-wake cycle, sleep architecture and circadian rhythm. At the intensive care unit at the Department of Anesthesiology at Køge Hospital, three out of nine rooms have a simulated circadian light installed. The idea is that this light rhythm may help to keep a natural circadian rhythm, minimizing the risk of delirium. With this descriptive and retrospective cohort study, the investigators therefore want to describe the incidence and possible risk- and preventive factors of delirium for the participants (ICU patients at Køge Hospital), and with a special focus on the possible effect of imitated circadian light..

Official Title
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Delirium at the Intensive Care Unit - a Retrospective Cohort Study

Conditions
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Delirium, Intensive Care Unit Syndrome

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients >18 years of age admitted to the ICU at Køge Hospital in the study period Exclusion Criteria: Richmond Agitation Sedation Score (RASS): -4 or -5 during the whole study period No CAM-ICU scores during the ICU stay Unable to communicate in Danish (aphasic, deaf, non-Danish speaking, severe brain damage) Severe dementia documented in electronic patient charts (OPUS) Patients not receiving active treatment (moribund patients)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Delirium at any time point | Incidence of patients with delirium during ICU-stay defined as at least one positive Confusion Assessment Method for the ICU (CAM-ICU) score or CAM-ICU negative delirium treated with anti-psychotics. | Throughout study period, up to 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Days with delirium | Days with positive CAM-ICU or CAM-ICU negative delirium treated with anti-psychotics in relation to length of stay (LOS) | Throughout study period, up to 6 months | 
| Circadian light exposure | Difference in incidences of delirium between patients admitted to rooms with circadian rhythm lighting and standard rooms | Throughout study period, up to 6 months | 
| Delirium in patients treated with hypnotics | Difference in incidence of delirium in patients treated with hypnotics before admission to hospital (ATC N05C) compared to those who are not | Throughout study period, up to 6 months | 
| Delirium in patients treated with steroids | Differences in incidences of delirium in patients that are treated with systemic steroids vs. no treatment | Throughout study period, up to 6 months | 
| Mortality | Mortality within ICU stay | Throughout study period, up to 6 months | 
| Demographic differences | Incidence of delirium associated to demographic variables (age, gender) | Throughout study period, up to 6 months | 
| Delirium and Simplified Acute Physiology Score (SAPS) | Incidence of delirium associated to Simplified Acute Physiology Score (SAPS) II | Throughout study period, up to 6 months | 
| Delirium related to number of ventilator days | Incidence of delirium associated to number of ventilator days | Throughout study period, up to 6 months | 
| Delirium related to sedation | Incidence of delirium associated to sedation infusion | Throughout study period, up to 6 months | 
| Delirium related to admission type | Incidence of delirium associated to admission type (medical/elective surgical/acute surgical) | Throughout study period, up to 6 months | 
| Distribution of types of delirium | Incidence and distribution of delirium subtypes (hypoactive/hyperactive/mixed) | Throughout study period, up to 6 months |