How is delirium managed in the Intensive Care Unit (ICU) setting?

Management of Delirium in the ICU

Implement routine delirium screening using CAM-ICU or ICDSC every 8-12 hours, prioritize early mobilization as first-line prevention and treatment, avoid benzodiazepines, and use dexmedetomidine over other sedatives when sedation is required. 1, 2

Systematic Delirium Monitoring

All adult ICU patients require routine delirium screening using validated tools 3:

• Use CAM-ICU as the preferred screening tool due to superior psychometric properties (weighted score 19.6/20), taking less than 2 minutes to complete 1
• Alternatively, use ICDSC (weighted score 16.8/20) which assesses 8 domains over current and previous nursing shifts 1
• Screen every 8-12 hours (at least once per shift) starting within 24-48 hours of admission 1
• Without validated tools, clinicians miss the majority of delirium cases, particularly hypoactive delirium which occurs more frequently than hyperactive delirium 1, 4

Mandatory monitoring is required for high-risk patients 1:

• History of alcoholism, cognitive impairment, or hypertension
• Severe sepsis or shock
• Mechanical ventilation
• Receiving parenteral sedatives and opioids

Non-Pharmacological Interventions (First-Line)

Early mobilization is the single most effective intervention to reduce delirium incidence and duration 3, 2:

• Mobilize patients as early as feasible, even while mechanically ventilated 3, 2
• This intervention reduces ICU and hospital length of stay and increases ventilator-free days 2
• A multifaceted approach reduced delirium rates from 70% to 29% over sustained implementation 5

Implement environmental and sleep optimization 2:

• Control light exposure: adequate lighting during daytime, darkness at night
• Reduce noise levels, particularly at night
• Cluster patient care activities to minimize nighttime interruptions
• Provide cognitive stimulation and reorientation using familiar objects 2
• Optimize sensory function: ensure patients have glasses and hearing aids 2

Pharmacological Management

Sedation Strategy

Avoid benzodiazepines whenever possible as they are a significant risk factor for developing delirium 3, 2:

• Use dexmedetomidine as the preferred sedative for delirious ICU patients (except in alcohol or benzodiazepine withdrawal) 2
• Two randomized controlled trials showed ~20% lower delirium prevalence with dexmedetomidine compared to benzodiazepines 3
• Implement an analgesia-first approach: treat pain before using sedatives 2
• Maintain light levels of sedation through daily sedation interruption or careful titration 2

Antipsychotic Use

No pharmacologic delirium prevention protocol is recommended as compelling data are lacking 3:

• Haloperidol does not reduce delirium duration based on current evidence 2
• Atypical antipsychotics may reduce delirium duration, but evidence is limited 2
• Do not use antipsychotics prophylactically to prevent delirium 2

Consider low-dose antipsychotics only for specific situations 4:

• Severely agitated patients with distressing psychotic symptoms
• Patients threatening substantial harm to themselves or others
• Symptoms refractory to nonpharmacologic interventions

Critical safety caveat: Avoid antipsychotics in patients with baseline QT prolongation, history of Torsades de Pointes, or concurrent QT-prolonging medications 2

Identify and Address Underlying Causes

Conduct focused evaluation for reversible causes 4:

• Medications (particularly anticholinergics, benzodiazepines)
• Infections and sepsis
• Metabolic derangements (electrolytes, glucose, hepatic/renal dysfunction)
• Alcohol or drug withdrawal
• Inadequately treated pain
• Hypoxia or hypercarbia

Special consideration for alcohol withdrawal: Initiate benzodiazepines within 6-24 hours to prevent progression to delirium tremens, and provide thiamine supplementation 4

Risk Factors to Recognize

Baseline risk factors significantly associated with ICU delirium 3:

• Preexisting dementia
• History of hypertension
• Alcoholism (≥2-3 drinks daily)
• High severity of illness at admission

Coma is an independent risk factor: Sedative-induced coma and multifactorial coma (but not medical coma alone) significantly increase delirium risk 3

Implementation Strategy

Use a multicomponent bundled approach 2, 6:

• Integrate pain, agitation, and delirium management into daily checklists
• Implement sedation protocols emphasizing light sedation targets
• Train all ICU staff (physicians, nurses, physiotherapists) on delirium screening tools 7
• Involve families in care and provide education about delirium 4

Common pitfalls to avoid 2:

• Overreliance on pharmacological interventions without addressing environmental factors
• Failure to identify and treat underlying causes
• Missing hypoactive delirium due to lack of systematic screening
• Continuing antipsychotics after ICU discharge without clear indication

Clinical Significance

Delirium is associated with increased mortality, prolonged ICU and hospital stays, and development of long-term cognitive impairment after ICU discharge 1, 2. Approximately one-third of delirium cases can be prevented or reversed through systematic risk-factor modification 4. The evidence strongly supports that prevention through nonpharmacologic interventions is far more effective than pharmacologic treatment once delirium develops 6.