Chest
Recent Advances in Chest MedicineThe Importance of Diagnosing and Managing ICU Delirium
Section snippets
Why Should We Monitor for Delirium?
For many years, the critical care community has focused on assessing, preventing, and reversing multiorgan dysfunction syndrome. However, the brain has been subjected to relatively little formal study until recently. ICU patients, especially older persons, are among the most vulnerable hospitalized patients for the development of delirium. Studies234567 have found that delirium develops in 20 to 50% of lower-severity ICU patients or those not receiving mechanical ventilation, and in 60 to 80%
What Is Delirium?
Delirium is defined by the Diagnostic and Statistical Manual of Mental Disorders34 as a disturbance of consciousness with inattention accompanied by a change in cognition or perceptual disturbance that develops over a short period (hours to days) and fluctuates over time. Although there are many hypothesized pathophysiologic mechanisms involved in the development of delirium, most are thought related to imbalances in neurotransmitters that modulate cognition, behavior, and mood. Varied terms
How Do We Monitor for Delirium?
The Society of Critical Care Medicine (SCCM) guidelines47 recommend monitoring delirium routinely in patients receiving mechanical ventilation. There are currently two validated tools for monitoring delirium in ICU patients: the Intensive Care Delirium Screening Checklist48 and the Confusion Assessment Method for the ICU (CAM-ICU).47 The Intensive Care Delirium Screening Checklist (Table 1) is an eight-item checklist with a sensitivity of 99% and specificity of 64% and interrater reliability of
Risk Factors/Etiology: What Are the Modifiable Risk Factors?
One key strategy to prevent or diminish delirium is to identify and modify risk factors that lead to delirium. Inouye et al5455 developed a predictive model for delirium in the elderly non-ICU patients that classified risk factors into two categories: predisposing (baseline vulnerability) and precipitating (hospital related or iatrogenic).55 Numerous risk factors have been identified in non-ICU populations754555657 that fall into these categories, and ICU patients have an average of 11 ± 4
Nonpharmacologic Prevention and Treatment
In the non-ICU setting, risk factor modification has resulted in a 40% relative reduction in the development of delirium.64 Modifications include repeated reorientation of patients, repetitive provision of cognitively stimulating activities for the patients, nonpharmacologic sleep protocol, early mobilization, range-of-motion exercises, timely removal of catheters and physical restraints, use of eye glasses and magnifying lenses, hearing aids and earwax disimpaction, adequate hydration, use of
Conclusions
Although delirium research in critical care is rapidly maturing, the weight of evidence already demonstrates that critical care clinicians cannot afford to ignore this form of organ dysfunction in our patients (Table 5). If we are to be comprehensive in our approach to monitoring and managing organ dysfunction, the brain should be a very active component of our daily discussion at the bedside in the ICU. This article has outlined key reasons to “tip” delirium onto the physician's “radar screen”
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2020, Critical Care NurseCitation Excerpt :However, these efforts have not significantly improved the recognition of delirium or the management of adverse consequences for most patients. This shortcoming may be due in part to a lack of coordinated educational efforts and the complexity of the syndrome itself.16-18 Routine assessment of delirium using standardized bedside screening tests is essential.
Dr. Ely was supported by National Institutes of Health grants RO1 AG 072701A1 and AG 01023–01A1 and the VA Merit Review Clinical Science Research and Development, the Measuring the Incidence and Determining Risk Factors for Neuropsychological Dysfunction in ICU Survivors study.
Ms. Pun has received honoraria from Hospira, Inc. and Cardinal Health and serves as a consultant on research project for Hospira, Inc. Dr. Ely has received grant support and honoraria from Hospira, Pfizer, and Eli Lilly.