Question 6

Highest mark
?
Pass rate
?
Other SAQs in this topic:
Other SAQs in this paper:

Define delirium and describe your management approach to this problem in the ICU.

[Click here to toggle visibility of the answers]

College Answer

Definition:

The acute onset of a disturbance of consciousness with inattention, changes in cognition and/orperception, that fluctuates over time, occurs as a consequence of a general medical condition and isnot better accounted for by a pre-existing, established or evolving dementia.

Management:

  1. Early recognition of delirium.
  1. Stabilise and ensure safety of the patient:
    • Attend to airway, breathing and circulation issues as required.
  1. Consider and rule out any potentially life-threatening causes of delirium (comprehensive history and physical examination will provide clues):
    • Hypoxia
    • Hypoglycaemia
    • Intra-cerebral haemorrhage
    • Meningitis/Encephalitis
    • Poisoning
    • Wernicke’s Encephalopathy
    • Infection: local (wound, anastomotic leaks etc.), UTI, lung etc.
    • Withdrawal from drugs
    • Hypertensive encephalopathy
    • Metabolic derangements – sodium, renal, liver.
  1. Consider non-pharmacological strategies to control symptoms:
    • Application of hearing aids, spectacles and dentures if worn.
    • Continuous re-orientation of patient - verbal, visual with photographs etc.
    • Enlist help of family members and/or interpreters.
    • Ensure as close to normal as possible sleep/wake cycles in a quiet and calm environment.
    • Treat pain, constipation, urinary retention if present.
    • Check drug chart and beware/attend to poly-pharmacy and cessation of drugs associated with delirium.
    • Mobilise early.
    • Avoid physical restraints if safe to do so.
  1. Obtain pharmacological control of symptoms if necessary:
    • Anti-psychotics are first line agents e.g. haloperidol, olanzepine, quetiapine.
    • Haloperidol 1-5mg iv q30 PRN. Dose can be doubled and repeated. Beware long QTc.
    • Benzodiazepines as first line agents for alcohol withdrawal only. Often used in combination with anti-psychotics in difficult to control symptoms in non-alcohol withdrawal delirium.
  1. Treat cause if found:
  2. O2, antibiotics, thiamine, glucose, electrolyte replacement, intra-venous fluids if dehydrated.

13

Investigations:

Directed by history, physical examination and differential diagnosis but include/consider;

Basic:

FBC, EUC, Glucose, LFT, ABG, CXR, ECG, Urinalysis + Dipstick, Septic screen, Urinary Drug Screen.

Advanced:

CT Brain, LP, TTE.

Discussion

Delirium is a favourite of the examiners. It is discussed in greater depth elsewhere ("Delirium in the ICU")

In order to simplify revision, I reproduce the salient points here:

The DSM -V diagnostic criteria for delirium:

  • Disturbance in attention and awareness.
  • Change in cognition
  • The disturbance develops over a short period and tends to fluctuate
  • There is evidence from the history, physical examination, or laboratory findings that the disturbance is caused by a direct physiologic consequence of a general medical condition, an intoxicating substance, medication use, or more than one cause.

A systematic approach to this question would resemble the following:

Urgently exclude and manage any lifethreatening aetiologies of delirium:

A) - Look for airway compromise due to decreased level of consciousness

B) - Assess for hypoxia and hypercapnea

C) - Assess for hypotension (thus cortial hypoperfusion) or hypertension (thus, hypertensive encephalopathy)

D) - Exclude hypoglycaemia and intoxication or poisoning; investigate for focal intracranial causes of delirium, such as intracranial haemorrhage or space-occupying lesion. Think about non-convulsive status epilepticus as the cause of delirium. Also consider withdrawal from alcohol and other drugs.

E) - Evaluate electrolytess, looking for hyponatremia

F) - Assess renal function, looking for uremia and dehydration

G) - Assess hepatic function, suspecting hepatic encephalopathy. Don't forget Wernicke's.

H) - Assess bone marrow function - cytopenia may be a clue to a space-occupying metastatic lesion, whereas blood film findings such as macrocytosis may suggest a chronic nutritional deficiency associated with alcoholism or IV drug abuse.

I) - Assess temperature, inflammatory markers and features of sepsis, ranging from UTI to septic shock (thinking about septic encephalopathy). Consider neurosyphilis and think about meningitis or encephalitis.

Investigation of delirium:

Stemming from the abovementioned differentials,

  • ABG
  • Urinalysis
  • EUC
  • CMP
  • FBC
  • Blood film
  • Inflammatory markers
  • CT brain
  • EEG
  • Lumbar puncture

Management of delirium

Non-pharmacological:

    • Good analgesia
    • Clear and firm communication with the patient
    • Frequent re-orientation
    • Family presence
    • Low-noise environment
    • Restoration of hearing aids and spectacles
    • Avoidance of sleep disturbance, promotion of normal sleep–wake cycle.
    • Avoidance of physical restraints
    • Early removal of IV lines and IDCs

Pharmacological:

    • Dexmedetomidine
    • Atypical antipsychotics
    • Classical antipsychotics
    • Benzodiazepines (if withdrawing from alcohol or benzodiazepines)

References

Oh's Intensive Care manual: Chapter 49   (pp. 549) Disorders  of  consciousness  by Balasubramanian  Venkatesh

Girard, Timothy D., Pratik P. Pandharipande, and E. Wesley Ely. "Delirium in the intensive care unit." Critical Care 12.Suppl 3 (2008): S3.

Ely, E. Wesley, et al. "Evaluation of delirium in critically ill patients: validation of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU)."Critical care medicine 29.7 (2001): 1370-1379.

O'Keeffe, SHAUN T., and JOHN N. Lavan. "Clinical significance of delirium subtypes in older people." Age and ageing 28.2 (1999): 115-119.

Barr, Juliana, et al. "Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit." Critical care medicine 41.1 (2013): 263-306.

Ouimet, Sébastien, et al. "Incidence, risk factors and consequences of ICU delirium." Intensive care medicine 33.1 (2007): 66-73.

Girard, Timothy D., et al. "Delirium as a predictor of long-term cognitive impairment in survivors of critical illness." Critical care medicine 38.7 (2010): 1513.

Hopkins, Ramona O., and James C. Jackson. "Long-term neurocognitive function after critical illness." CHEST Journal 130.3 (2006): 869-878.

van den Boogaard, Mark, et al. "Incidence and short-term consequences of delirium in critically ill patients: a prospective observational cohort study."International journal of nursing studies 49.7 (2012): 775-783.

Stevens, Robert D., Karin J. Neufeld, and Tarek Sharshar. "Delirium in the ICU: time to probe the hard questions." Crit Care 15.1 (2011): 118.

van Boogaard, M., et al. "Development and validation of PRE-DELIRIC (PREdiction of DELIRium in ICu patients) delirium prediction model for intensive care patients: observational multicentre study." BMJ: British Medical Journal344 (2012).

Van Rompaey, Bart, et al. "Risk factors for intensive care delirium: a systematic review." Intensive and Critical Care Nursing 24.2 (2008): 98-107.

Schweickert, William D., et al. "Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial."Lancet (London, England) 373.9678 (2009): 1874-1882.

Skrobik, YoannaK, et al. "Olanzapine vs haloperidol: treating delirium in a critical care setting." Intensive care medicine 30.3 (2004): 444-449.

Milbrandt, Eric B., et al. "Haloperidol use is associated with lower hospital mortality in mechanically ventilated patients*." Critical care medicine 33.1 (2005): 226-229.

Moots, R. J., et al. "Old drug, new tricks: haloperidol inhibits secretion of proinflammatory cytokines." Annals of the rheumatic diseases 58.9 (1999): 585-587.

Page, Valerie J., et al. "Effect of intravenous haloperidol on the duration of delirium and coma in critically ill patients (Hope-ICU): a randomised, double-blind, placebo-controlled trial." The Lancet Respiratory Medicine 1.7 (2013): 515-523.

Gilchrist, Neil A., Ifeoma Asoh, and Bruce Greenberg. "Atypical antipsychotics for the treatment of ICU delirium." Journal of intensive care medicine 27.6 (2012): 354-361.

Jasiak, Karalea D., et al. "Evaluation of discontinuation of atypical antipsychotics prescribed for ICU delirium." Journal of pharmacy practice 26.3 (2013): 253-256.

Inouye, Sharon K., et al. "A multicomponent intervention to prevent delirium in hospitalized older patients." New England journal of medicine 340.9 (1999): 669-676.

Girard, Timothy D., et al. "Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial." The Lancet 371.9607 (2008): 126-134.

Mehta, Sangeeta, et al. "Daily sedation interruption in mechanically ventilated critically ill patients cared for with a sedation protocol: a randomized controlled trial." JAMA 308.19 (2012): 1985-1992.

Devlin, John W., et al. "Efficacy and safety of quetiapine in critically ill patients with delirium: A prospective, multicenter, randomized, double-blind, placebo-controlled pilot study*." Critical care medicine 38.2 (2010): 419-427.

Kim, Sung‐Wan, et al. "Risperidone versus olanzapine for the treatment of delirium." Human Psychopharmacology: Clinical and Experimental 25.4 (2010): 298-302.

Grover, Sandeep, Vineet Kumar, and Subho Chakrabarti. "Comparative efficacy study of haloperidol, olanzapine and risperidone in delirium." Journal of psychosomatic research 71.4 (2011): 277-281.

Yoon, Hyung-Jun, et al. "Efficacy and safety of haloperidol versus atypical antipsychotic medications in the treatment of delirium." BMC psychiatry 13.1 (2013): 1-11.

[Submit a comment or correction]