DOSM STUDY

DOSM is a prospective observational cohort study which assesses the feasibility of using depth of sedation monitors to reduce delirium in critically ill patients. Delirium impacts many patients in the ICU and causes confusion, agitation, and changes in mental abilities. ICU delirium can contribute to thinking problems, increase risk of death in-hospital, and lead to poor recovery after hospital discharge. DOSM will explore the association of depth of sedation scores received from these monitors with delirium and other patient and health system outcomes. 

The DOSM study is crucial and relevant to investigate as current methods of determining the depth of sedation use clinical sedation scores which simply rely on qualitative factors such as evoking motor responses to verbal or painful stimuli. As a result, these methods are ineffective in patients who are most vulnerable to sedation-associated delirium (SAD): patients with brain injuries, intoxications, or those requiring deep sedation or muscle paralysis to facilitate ventilation. 

This contributes to a vicious cycle, whereby high sedative dosing leads to sedation tolerance and dose escalation. Weaning sedation triggers withdrawal and agitation that manifest as delirium and result in the resumption of sedation. Developing objective methods to monitor sedation depth in critically ill patients accurately is an important clinical problem requiring urgent and innovative solutions.

The DOSM study will help us understand if new monitors can help reduce ICU delirium and improve outcomes in critically ill patients receiving invasive mechanical ventilation. DOSM will help establish the groundwork for an interventional randomized control trial (RCT) that aims to reduce delirium in ICU patients requiring sedation and improve associated patient outcomes and health system outcomes via personalized sedation strategies guided by depth of sedation monitors.

Enrolment Criteria:

• Adult (age ≥18 years)

• Admitted to the ICU within the previous 24 hours requiring sedation to tolerate mechanical ventilation 

We will exclude patients with:

• Prior known or suspected dementia

• Injuries preventing use of depth of sedation monitors

• Admitted with seizures or status epilepticus

• Pre-existing limitations on life-sustaining therapies at ICU admission

If a patient agrees to participate in the study, we will use depth of sedation monitors for up to 72 hours to record the depth of sedation. We will also collect clinical information such as sedative medications, vital signs, and the clinical sedation and delirium scores that doctors and nurses record as part of routine clinical care. These measurements will not be used to change treatment decisions and we will not be performing additional tests not already done for routine care.