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JoukoLaurila

Delirium

Essentials

  • Delirium or acute confusional state is an extensive, rapid-onset disturbance of brain function due to an organic cause. In the elderly, any change in the balance of health can trigger it.
  • Delirium is difficult to recognize (more than half of the cases remain unrecognized) and the prognosis is poor.
  • Delirium increases the incidence of complications and mortality during hospitalization.

Prevalence and prognosis

  • Delirium occurs in 10-40% of the elderly during hospital care. Physicians recognize only one third of the cases.
  • The patient may recover even from a delirium that has endured for several weeks.
  • The mortality caused by delirium is up to 25%, and up to 40% of the oldest patients end up in institutional care.
  • In acute diseases, effective fluid therapy, pain management, oxygenation, nutrition, optimization of drug therapy, mobilization and maintenance of orientation and sleep rhythm (without drugs) reduce the incidence of delirium by about 50%.

Symptoms

  • Delirium is manifested by impairment of attention and apperception (attention deficit) and disorganized logical thinking. Consciousness becomes clouded and cognitive functions are suddenly deteriorated.
  • Delirium is often associated with hallucinations and aberrant thoughts, disorders of the sleep-wake schedule, alteration of psychomotor activity, desorientation, impairment of memory and fluctuations of mood.
  • Clinical features develop over a short period of time and tend to fluctuate over the course of the day.

Predisposing factors

  • Advanced age
  • Degenerative brain diseases (especially memory diseases)
  • Severe somatic illnesses (e.g. cancer)
  • Polypharmacy (especially anticholinergic drugs and opioids)
  • Impairment of vision and hearing, sleeplessness, unfamiliar environment, physical restraints
  • Surgical operations

Triggering factors

  • A variety of underlying conditions can cause delirium.
  • Medications
    • Drugs with anticholinergic properties (tricyclic antidepressants, phenothiazines, hydroxyzine, biperiden)
    • Opioids, sedatives, levodopa, lithium, bromocriptine, steroids, many antimicrobials (such as quinolones and clindamycin)
    • Abrupt discontinuation of a regularly used anxiolytic or of alcohol use (delirium tremens, see also Treatment of Alcohol Withdrawal)
  • Infections
    • Pyelonephritis, pneumonia, sepsis, erysipelas, meningitis, febrile viral infections
  • Cardiovascular diseases
    • Myocardial infarction, arrhythmias, pulmonary embolism, hypotension, etc.
  • Cerebrovascular diseases
    • Cerebral infarction, TIA, cerebral haemorrhage, subarachnoid haemorrhage
  • Metabolic and endocrinological disorders
    • Disorders in acid-base balance, disorders in fluid and electrolyte balance, hypoalbuminaemia, hypophosphataemia, insufficiency of the liver, kidneys or lungs, hypo- or hyperglycaemia, hypo- or hyperthyroidism, disorders of calcium balance, deficiencies of different B-vitamins, anaemia, other endocrinological disorders
  • Others
    • Traumas (head injuries, burns, hip fracture, surgery, etc.)
    • Epilepsy, postictal state
    • Tumours (intracerebral, pulmonary), myeloma
    • Poisoning (e.g. digoxin)
    • Big life changes (especially in patients with memory disease)

Diagnosis

  • History: When was the patient last well? Course of symptoms? Cognition before the illness? Usage of medications? Usage of alcohol?
  • The cause of delirium is often multifactorial. Its diagnostics aims to identify and treat, in particular, acute diseases or diseases which have become acute and to restore the body's homeostasis.
  • Careful physical examination
  • CRP, basic blood count with platelet count, plasma sodium, potassium, creatinine, blood glucose, ECG
  • As needed: chemical urinalysis, TnT, ESR, glytamyl transferase, alkaline phosphatase, TSH, free T4, albumin-corrected calcium, vitamin B12, fasting serum folate and arterial blood gas analysis, etc.
  • Chest x-ray
  • Analysis of cerebrospinal fluid, head CT scan, full body CT scan, EEG when needed

Differential diagnosis

  • Memory disease
    • Insidious onset and slow course, usually with no daily variation in the intensity of symptoms
    • Level of consciousness is normal, and attention intact until late stages
  • Psychosis
    • Level of consciousness is normal, cognitive functions are not globally disturbed. Speech is not totally disorganized. Also the psychiatric patient history is differrent.
    • Auditory hallucinations are common in psychosis, whereas visual hallucinations are more common in delirium.
  • Dementia and delirium are often seen in same patient.
  • The Confusion Assessment Method (CAM) is a good differential diagnostic tool (see e.g. http://help.agscocare.org/productAbstract/H00101). It is easy to use and has been validated in a number of different patient groups.

Management Droperidol for Psychosis-Induced Aggression or Agitation

  • Management of the underlying factors that triggered the delirium
  • Critical review of the patient's medication and reduction of dosage or discontinuation of any suspicious drugs (especially opioids, anticholinergic drugs) Managing the Medication of Elderly People
  • Management of the general condition: fluid and oxygen balance, taking care of urine flow and bowel function, prevention of bedsores and injuries, rehabilitation, adequate lighting, familiar objects.
    • Peaceful environment, unhurried conversation, orientation, closeness of the patient's own nurse, early mobilization
  • Thiamine 250 mg once daily intravenously for 3-5 days
    • If Wernicke encephalopathy is suspected, thiamine is administered 250 mg 3 times daily intravenously, even for weeks.
  • In severe cases (severe restlessness, distressing hallucinations) as short as possible symptomatic drug therapy, starting from dosage
  • In alcoholic delirium, the first-line treatment is an anxiolytic. In elderly persons, lorazepam or oxazepam is used instead of diazepam that has a long half-life, until the patient is sleeping Treatment of Alcohol Withdrawal.
  • After recovery from delirium, the patient often feels anxious because of the bewildering experience. Going through of the episode is beneficial for the recovery.

    References

    • Hshieh TT, Inouye SK, Oh ES. Delirium in the Elderly. Clin Geriatr Med 2020;36(2):183-199 [PubMed]
    • Shenvi C, Kennedy M, Austin CA, et al. Managing delirium and agitation in the older emergency department patient: the ADEPT Tool. Ann Emerg Med 2020;75(2):136-145. [PubMed]
    • Nikooie R, Neufeld KJ, Oh ES, et al. Antipsychotics for treating delirium in hospitalized adults: a systematic review. Ann Intern Med 2019;171(7):485-495. [PubMed]
    • Hshieh TT, Yue J, Oh E, et al. Effectiveness of multicomponent nonpharmacological delirium interventions: a meta-analysis. JAMA Intern Med 2015;175(4):512-20. [PubMed]