Edinburgh Delirium Research Group

Edinburgh Delirium Test Box for the Intensive Care Unit

The EDTB-ICU was developed by adapting existing Delbox tasks for use in the Intensive Care Unit (ICU). Delirium is highly prevalent in this setting, affecting between 30-80% of all patients; however the detection and assessment of delirium in the ICU is made difficult by the high proportion of patients that are unable to speak because of mechanical ventilation, and high levels of patient sedation.

The EDTB-ICU was designed to address several limitations of existing ICU delirium screening instruments by providing a brief screening instrument that is objective, provides a rating of symptom severity, and tailors response methods to the patient’s physical abilities.

Patients first undergo a brief behavioural assessment, which examines the patient’s level of arousal, their ability to track moving visual stimuli, and then their ability to follow a simple command. This assessment helps to establish whether the patient is alert enough to follow simple instructions that will allow them to complete the Delbox task in a meaningful way, and helps to identify a suitable method of response that is appropriate to the patient’s physical abilities. Patients then complete a brief sustained attention task where they are asked to count the number of times a single target light illuminates on the EDTB2 test box, and then to indicate the number of lights they saw, using a multiple-choice response card. Over three levels (each comprised of three trials), task difficulty is increased through increasing presence and frequency of ‘distractor’ lights surrounding the target light.

Pilot investigations among 20 ICU patients revealed that these tasks were well tolerated by this population, and further longitudinal investigations among 30 ICU patients revealed that EDTB-ICU tests were highly sensitive (100%) and specific (92%) for the detection of delirium (as diagnosed using the CAM-ICU), with patient performance fluctuating over time in line with delirium diagnosis. Performance on the EDTB-ICU was not influenced by patient age, or their method of response.

These preliminary findings suggest that the EDTB-ICU provides a brief, objective, and sensitive method for screening for delirium in the ICU, which was well tolerated by patients in this setting. Future studies will aim to validate this instrument among larger samples of ICU patients, and against a reference-standard psychiatric diagnosis of delirium. A current project is investigating the use of Android smartphone technology to administer EDTB-ICU tests in the ICU.

Edinburgh Delirium Test Box
EDRG Home EDTB Home Sustained Counting Task Word Building Task EDTB-ICU Smartphone test	Edinburgh Delirium Test Box for the Intensive Care Unit The EDTB-ICU was developed by adapting existing Delbox tasks for use in the Intensive Care Unit (ICU). Delirium is highly prevalent in this setting, affecting between 30-80% of all patients; however the detection and assessment of delirium in the ICU is made difficult by the high proportion of patients that are unable to speak because of mechanical ventilation, and high levels of patient sedation. The EDTB-ICU was designed to address several limitations of existing ICU delirium screening instruments by providing a brief screening instrument that is objective, provides a rating of symptom severity, and tailors response methods to the patient’s physical abilities. Patients first undergo a brief behavioural assessment, which examines the patient’s level of arousal, their ability to track moving visual stimuli, and then their ability to follow a simple command. This assessment helps to establish whether the patient is alert enough to follow simple instructions that will allow them to complete the Delbox task in a meaningful way, and helps to identify a suitable method of response that is appropriate to the patient’s physical abilities. Patients then complete a brief sustained attention task where they are asked to count the number of times a single target light illuminates on the EDTB2 test box, and then to indicate the number of lights they saw, using a multiple-choice response card. Over three levels (each comprised of three trials), task difficulty is increased through increasing presence and frequency of ‘distractor’ lights surrounding the target light. Pilot investigations among 20 ICU patients revealed that these tasks were well tolerated by this population, and further longitudinal investigations among 30 ICU patients revealed that EDTB-ICU tests were highly sensitive (100%) and specific (92%) for the detection of delirium (as diagnosed using the CAM-ICU), with patient performance fluctuating over time in line with delirium diagnosis. Performance on the EDTB-ICU was not influenced by patient age, or their method of response. These preliminary findings suggest that the EDTB-ICU provides a brief, objective, and sensitive method for screening for delirium in the ICU, which was well tolerated by patients in this setting. Future studies will aim to validate this instrument among larger samples of ICU patients, and against a reference-standard psychiatric diagnosis of delirium. A current project is investigating the use of Android smartphone technology to administer EDTB-ICU tests in the ICU.