Master Delirium with Picmonic for Medicine

A key distinguishing feature of delirium is that the onset is not gradual and may be sudden, within minutes to hours to days.

Contrasted with dementia, delirium is reversible by treating the underlying cause of the condition, such as infection, hypoxia, drug intoxication, etc.

Delirium is characterized by a fluctuating course, meaning symptoms can vary in severity throughout the day, often worsening in the evening or at night. This waxing and waning pattern is a key distinguishing feature from other cognitive disorders like dementia, which tend to have a stable or progressively worsening course.

Delirium is always secondary to an underlying medical condition. Examples include infection, metabolic imbalance, medication effects, substance intoxication/withdrawal, or organ failure.

It is not a primary psychiatric disorder but a manifestation of an acute disturbance in brain function triggered by a systemic cause. Management of delirium includes finding the underlying cause and treating it.

A patient with delirium often has a short attention span. They may experience difficulty focusing and will require frequent reminding and refocusing on tasks they attempt to complete.

Delirium often leads to a decline in cognition. This decline may cause the patient to be disoriented in person, place, or time, experience poor judgment, and have impairments in memory.

An altered sleep-wake cycle is a common feature of delirium. This often presents as daytime drowsiness and nighttime agitation/insomnia. Patients may be awake at night and excessively sleepy during the day. This is because of a disruption in the normal circadian rhythm. Altered sleep-wake cycle is an early and sensitive indicator of delirium, and this helps distinguish delirium from other cognitive disorders like dementia.

Being “delirious” is often a combination of any or all three - hallucinations, delusions, and illusions. They may see, hear, or perceive things differently, fabricate them entirely, or misinterpret reality.

Illusions in delirium are misinterpretations of actual sensory input. For example, mistaking a coat on a chair for a person. It differs from hallucinations, which occur without external stimuli.

Electroencephalogram in delirium often shows diffuse background rhythm slowing, reflecting widespread brain dysfunction.

Useful in differentiating delirium (slowing) vs psychosis (normal EEG) vs seizure (epileptiform activity).

Treating the underlying cause is the primary management of delirium, but other than that, supportive measures are crucial. This may include nonpharmacologic interventions such as maintaining orientation with clocks and calendars, ensuring proper lighting, promoting normal sleep-wake cycles, and minimizing sensory overload or deprivation. Providing frequent reorientation, encouraging the presence of family members, and ensuring adequate hydration and nutrition can also help reduce the severity and duration of symptoms.

Antipsychotics such as haloperidol may be used short-term for severe agitation in delirium, especially when the patient poses a danger to themselves or others. Benzodiazepines should be avoided unless delirium is due to alcohol or benzodiazepine withdrawal.