Intensive care unit (ICU) psychosis (also called intensive care unit [ICU] syndrome) describes a group of serious psychiatric symptoms of delirium that are unique to the ICU environment.
ICU delirium is associated with higher mortality rates. A meta-analysis found that ICU patients with delirium were three times more likely to die than patients without delirium and six times more likely to have one or more complications.
ICU psychosis may cause death if, for example, a patient falls or removes an IV with needed medication, but the delirium in itself does not cause death.
What Are Symptoms of ICU Psychosis?
Symptoms of ICU psychosis usually come on quickly and last 24 to 48 hours, though it can last as long as two weeks in some cases.
Symptoms of ICU psychosis are the same as those of delirium and may include:
- Fluctuating levels of consciousness
- Confusion and disorientation
- Visual hallucinations
- Abnormal behavior such as aggression or passivity
- Emotional or personality changes, with frequent mood changes, including anger, agitation, anxiety, apathy, depression, fear, euphoria, irritability, suspicion
- Slurred speech and language difficulties
- Saying things that don’t make sense
- Changes in feeling (sensation) and perception
- Loss of attention
- Inability to concentrate
- Changes in movement (restlessness or slow movement)
- Changes in sleep patterns
- Memory loss
- Disorganized thinking
- Signs of medical illness (such as fever, chills, pain, etc.) or medication side effects
Delirium is not the same as dementia, which develops slowly and progressively worsens.
What Causes ICU Psychosis?
ICU psychosis is believed to be caused by a person’s underlying medical condition and perhaps worsened by characteristics of the ICU, such as sleep deprivation and sensory overload or monotony.
The main cause of ICU psychosis is believed to be underlying medical factors. The most common underlying medical factors that may lead to ICU psychosis include:
- Metabolic disturbances
- Electrolyte imbalances
- Withdrawal syndromes
- Acute infection (intracranial and systemic)
- Head trauma
- Vascular disorders
- Intracranial space-occupying lesions
- Use of certain medications and substances, either through intoxication or withdrawal, such as anti-anxiety medications and narcotics
Other possible causes of ICU delirium include characteristics of the ICU and psychological factors, though generally none of these conditions cause delirium on their own.
- ICU environment (not a conclusive cause)
- Sleep deprivation
- Social isolation
- Unfamiliar surroundings
- Excessive noise
- Sensory monotony
- Absence of diurnal light variation
- Psychological factors
- Stress of being in the ICU
- Patients are extremely ill and in life-threatening situations
- Patients have multiple or serious medical problems
- They may be unable to communicate their needs
- There is a loss of personal control
- Patients are in a new and threatening environment
- Stress of being in the ICU
- Cognitive status prior to ICU admission
- A patient’s prior cognitive level and age may predispose a patient to delirium
How Is ICU Psychosis Diagnosed?
A diagnosis of ICU delirium can be difficult to make, due to the patient’s medical state and because symptoms of dementia can often resemble those of delirium.
In order to diagnose ICU psychosis, other conditions that can cause similar symptoms must be ruled out, such as:
- Low blood sugar (hypoglycemia)
- Infection or sepsis
- Side effects or interactions of medications
- Drug or alcohol withdrawal
Tests to determine the underlying cause for the symptoms may include:
What Is the Treatment for ICU Psychosis?
ICU delirium is reversible and treatable in most cases. Treating the underlying medical condition can often reverse symptoms of delirium.
Other treatments for ICU delirium include:
- Adequate fluid and electrolyte balance
- Adequate nutrition and vitamin supply
- Weaning patients off breathing machines sooner
- Providing the patient an environment in which they can get better sleep and allowing patients to preserve their normal sleep-wake cycles
- Using medications that may be less likely to trigger delirium
- Providing adequate pain relievers if needed
- Establishing clear communication with the patient
- Reorienting the patient to time and place frequently
- Involving family members in care