Module 3: Delirium

Sections:

1. Guiding Principles
2. Delirium Assessment
3. Medications
4. Delirium Management
5. Weaning medications
6. Links to Drug Monographs
7. Return to main menu
8. Take the test

1. Guiding Principles

• Delirium is very common among critically ill patients, is an independent risk factor for morbidity and mortality and is undiagnosed in about 60% of patients. It is characterized by disorganized thinking, inattention and acute change in level of consciousness.

  Defining features include:

  • acute onset
  • disordered attention
  • cognitive dysfunction
  • altered level of consciousness
  • and fluctuation of each of these characteristics

  Predisposing factors for delirium:

  • polypharmacy (patient receiving 3 or more drugs)
  • use of use of narcotics, benzodiazepines
  • infection
  • organ dysfunction (renal, cardiac, respiratory, hepatic)
  • electrolyte abnormalities
  • changes in hydration
  • altered vision or hearing
  • disruption in sleep pattern
• Delirium can manifest as either hyperactive (e.g., agitated) or hypoactive (e.g., often not identified at all or misdiagnosed as depression).
• Sedatives alone, or the combination of sedatives and analgesics can worsen delirium.
• There are 3 main neurotransmitters involved in the pathophysiology of delirium: acetylcholine, dopamine, and aminobutyric acid.
• While dopamine excites the brain, the other 2 provide an antagonistic action to counter balance the dopamine.
• Delirium is caused by an imbalance among the neurotransmitters in the brain, resulting in unpredictable and inconsistent neurotransmission.
• Any disease process or medication that disrupts these neurotransmitters predisposes the patient for delirium (e.g., hypoxia, dehydration, acute brain injury, use of anti-cholinergic agents which block the acetylcholine).

An alert and oriented patient demonstrates both arousal and attention:

• Arousal is assessed using the VAMASS.
• Attention is assessed through conservations with the patient or by using a delirium assessment scale.

Is it important to treat delirium?

• Failure to recognize delirium early on can adversely impact patient outcomes.
• Delirium, or ICU psychosis, cannot be resolved by transferring the patient out of ICU.
• The first behavior observed is anxiety and/or restlessness – if not treated appropriately, it can escalate to confusion and agitation.
• Treatment of delirium includes medications, environmental and supportive strategies.
• Treatment with sedatives alone, or the combination of sedatives and analgesics can worsen delirium.
• Treatment of alcohol withdrawal related delirium.

  Terminology:

1. Agitation: description of a behavior

• Not always associated with delirium.
• Can be due to hypoxia, pain, fear or frustration.

2. Confusion: disturbed orientation related to person, place or time

3. Dementia: gradual onset over time whereas delirium is rapid onset

• Memory disturbances and personality/mood changes but no clouding of consciousness.

4. Delirium: is a sudden onset of disturbed cognitive function and inattention, and these behaviors fluctuate throughout the day and night

2. Delirium Assessment

• Every patient will be screened for delirium risk every shift and prn using the ICU Delirium Screening Checklist

  Exceptions:

• Patients scoring a VAMASS of < 2 (comatose or anesthetized)
• Acute neurosurgical or neurological (e.g., SAH, stroke)
• Acute alcohol withdrawal

  Once acute event has passed, these patients will also be assessed every shift. Delirium assessment must be done in conjunction with pain and sedation assessment.
  

  Process:

  • Assess patients q 12 hours with ICU Delirium Screening Checklist
  • If score is 4 or greater, assess with CAM ICU scale
  • If CAM ICU is positive, treat as either hypoactive or hyper active delirium depending on VAMASS score

3. Medications

• Treatment of choice is combination therapy using haloperidol and lorazepam.
  • Haloperidol acts by blocking the dopamine receptors.
  • Lorazepam enhances the action of the inhibitory neurotransmitter GABA by acting at the GABA receptor.
• The haloperidol dose is two times the lorazepam dose, otherwise called the H2A rule.
• Haloperidol and lorazepam are scheduled around the clock, with prn dosing available for acute exacerbations.
• The hs dose is larger than the daytime doses to enhance sleep and minimize “sundowning”.
• Lorazepam potentiates the tranquilizing effects of haloperidol, so less haloperidol would have to be given to achieve the same effect.
• Use of lorazepam/benzodiazepine alone in a delirious patient does not solve the neurotransmitter imbalance, and could further increase the agitation (paradoxical effect).
• Benzodiazepines are the treatment of choice if patient is experiencing acute alcohol withdrawal.
• Once confusion has cleared, continue haloperidol and lorazepam for 3-5 days, then start to wean.

4. Delirium Management

• For patients with pre-existing history of Parkinson’s disease or extra-pyramidal dysfunctions – consult psychiatry before initiating drug therapy. Use of haloperidol can exacerbate these conditions.
• Management includes both medications and environmental/supportive strategies.
• Environmental strategies include: music, noise reduction, frequent reorientation, orientation with familiar things, promotion of sleep/wake cycles.

Delirium Protocol: Treatment - (Not for Delirium Tremens from Acute Alcohol Withdrawal)
	Is the Intensive Care Delirium Screening Checklist score > or = 4 AND is the CAM ICU Score Positive?
		Yes?
NO? Consider Hypoactive Delirium and treat as follows:		Is the VAMASS > or = 4?		Yes? Treat as Hyperactive Delirium as follows:
Treat cause. Assess sedation administration. Assess for polypharmacy. Modify environment. Assess for depression. Consider low doses of scheduled haloperidol (e.g., 0.25 - 0.5 mg IV/po bid).		Treat cause/ modify environmental stimuli. Initiate haloperidol (1.0 - 2.5 mg IV q 10 minutes) and lorazepam (2 mg IV q10 minutes) until initial and severe agitation is controlled. Continue with scheduled lorazepam and haloperidol q 6hrs with larger dose at hs. Increase doses according to agitation; maintain a ratio of ~ 2mg of haloperidol to 1 mg of lorazepam. Continue scheduled dosing until agitation decreases, target VAMASS score is achieved and delirium scores are negative. Taper scheduled dosing over 3 days, beginning with daily lorazepam dose only. Reduce haloperidol dose second, followed by hs lorazepam. If haloperidol is contraindicated (e.g., Parkinson's), consult psychiatry/pharmacy (consider olanzepine). Watch for side effects of haloperidol including: dystonic reactions (e.g., increased tone, unusual mouth or eye movement) malignant neuroleptic syndrome (e.g. increased CK, fever, metabolic alkalosis, rigidity, hyperkalemia) prolonged QT intervals

5. Weaning Medication

• Once you have adequate behavioural control and are at the VAMASS target, initiate weaning.
• Begin by weaning the daytime lorazepam dose.
• Wean the haloperidol dose after the daytime lorazepam is weaned to .5 mg per dose.
• Do not wean hs lorazepam until after haloperidol has been weaned off.
• Aim to wean the drugs over approximately 3 - 4 days (consult with pharmacy or psychiatry).
• The goal of tapering is to have a patient who is awake, within the target VAMASS range, without an increase in the level of agitation.

Example of Weaning Schedule:

Step One:

• Initiate weaning of daily lorazepam.

DOSING TIMES	0400 hours	1000 hours	1600 hours	2200 hours
Haloperidol	5 mg	5 mg	5 mg	10 mg
Lorazepam	2 mg	2 mg	2 mg	4 mg

Step Two:

• If tolerated for 24 hours, wean daily lorazepam further.
• Do not change hs dose.

DOSING TIMES	0400 hours	1000 hours	1600 hours	2200 hours
Haloperidol	5 mg	5 mg	5 mg	10 mg
Lorazepam	1 mg	1 mg	1 mg	4 mg

Step Three:

• If tolerated for 24 hours, wean daily lorazepam further.
• Do not change hs dose.

DOSING TIMES	0400 hours	1000 hours	1600 hours	2200 hours
Haloperidol	5 mg	5 mg	5 mg	10 mg
Lorazepam	0.5 mg	0.5 mg	0.5 mg	4 mg

Step Four:

• Begin weaning of daily haloperidol dose.
• Do not change hs dose.

DOSING TIMES	0400 hours	1000 hours	1600 hours	2200 hours
Haloperidol	3 mg	3 mg	3 mg	10 mg
Lorazepam	0.5 mg	0.5 mg	0.5 mg	4 mg

 

• Continue weaning as tolerated, until only the hs doses remain. Gradually wean the hs medications until only a small dose (.5-1 mg of haloperidol) remains.

6. Links to Drug Monographs:

Haloperidol Monograph

Lorazepam Monograph

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Last Updated: May 23, 2005
Brenda Morgan, Clinical Educator, CCTC