Delirium is defined as an acute confusional state with a disturbance of consciousness and a change in cognition which is fluctuating and self-limited in the vast majority of the cases. It is common in intensive care, most frequently in its hypoactive manifestation, and is associated with increased morbidity and mortality. This article reviews the pathogenesis, risk factors, diagnostic assessment, prevention and management of delirium.
EelesEMHubbardREWhiteSV. Hospital use, institutionalisation and mortality associated with delirium. Age Ageing2010;39: 470–75.
2.
FongTGJonesRNShiP. Delirium accelerates cognitive decline in Alzheimer disease. Neurology2009;72: 1570–75.
3.
StagnoDGibsonCBreitbartW. The delirium subtypes: a review of prevalence, phenomenology, pathophysiology, and treatment response. Palliat Support Care2004;2: 171–79.
4.
McCuskerJColeMGVoyerP. Prevalence and incidence of delirium in long-term care. Int J Geriatr Psychiatry2011;26: 1152–61.
5.
GirardTDJacksonJCPandharipandePP. Delirium as a predictor of long-term cognitive impairment in survivors of critical illness. Crit Care Med2010;38: 1513–20.
6.
BalasMCHappMBYangW. Outcomes associated with delirium in older patients in surgical ICUs. Chest2009;135: 18–25.
7.
CerejeiraJFirminoHVaz-SerraAMukaetova-LadinskaEB. The neuroinflammatory hypothesis of delirium. Acta Neuropathol2010;119: 737–54.
8.
MaclullichAMFergusonKJMillerT. Unravelling the pathophysiology of delirium: a focus on the role of aberrant stress responses. J Psychosom Res2008;65: 229–38.
9.
RobertssonBBlennowKBraneG. Hyperactivity in the hypothalamic-pituitary-adrenal axis in demented patients with delirium. Int Clin Psychopharmacol2001;16: 39–47.
10.
FieldRHGossenACunninghamC. Prior pathology in the basal forebrain cholinergic system predisposes to inflammation-induced working memory deficits: reconciling inflammatory and cholinergic hypotheses of delirium. J Neurosci2012;32: 6288–94.
11.
FuruseTHashimotoK. Sigma-1 receptor agonist fluvoxamine for delirium in intensive care units: report of five cases. Ann Gen Psychiatry2010;9: 18.
12.
InouyeSK. Predisposing and precipitating factors for delirium in hospitalized older patients. Dement Geriatr Cogn Disord1999;10: 393–400.
13.
van MunsterBCde RooijSEKorevaarJC. The role of genetics in delirium in the elderly patient. Dement Geriatr Cogn Disord2009;28: 187–95.
14.
AbelhaFJFernandesVBotelhoM. Apolipoprotein E e4 allele does not increase the risk of early postoperative delirium after major surgery. J Anesth2012;26: 412–21.
15.
JonesRNFongTGMetzgerE. Aging, brain disease, and reserve: implications for delirium. Am J Geriatr Psychiatry2010;18: 117–27.
16.
The National Institute for Health/and Clinical Excellence. Delirium: diagnosis, prevention and management. (Clinical Guideline 103.) July 2012. www.nice.org.uk/CG103.
17.
ElyEWShintaniATrumanB. Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit. JAMA2004;291: 1753–62.
18.
LawlorPGGagnonBManciniIL. Occurrence, causes, and outcome of delirium in patients with advanced cancer: a prospective study. Arch Intern Med2000;160: 786–94.
19.
YoungJMurthyLWestbyM. Diagnosis, prevention, and management of delirium: summary of NICE guidance. BMJ2010;341: c3704.
20.
van den BoogaardMPickkersP. Development and validation of PRE-DELIRIC (PREdiction of DELIRium in ICu patients) delirium prediction model for intensive care patients: observational multicentre study. BMJ2012;344: e420.
21.
InouyeSK. Delirium in hospitalized older patients. Clin Geriatr Med1998;14: 745–64.
22.
LeeHBMearsSCRosenbergPB. Predisposing factors for postoperative delirium after hip fracture repair in individuals with and without dementia. J Am Geriatr Soc2011;59: 2306–13.
23.
ShiQPresuttiRSelchenDSaposnikG. Delirium in acute stroke: a systematic review and meta-analysis. Stroke2012;43: 645–49.
24.
McNicollLPisaniMAZhangY. Delirium in the intensive care unit: occurrence and clinical course in older patients. J Am Geriatr Soc2003;51: 591–8.
25.
BergeronNDuboisMJDumontM. Intensive Care Delirium Screening Checklist: evaluation of a new screening tool. Intensive Care Med2001;27: 859–64.
26.
PandharipandePShintaniAPetersonJ. Lorazepam is an independent risk factor for transitioning to delirium in intensive care unit patients. Anesthesiology2006;104: 21–6.
27.
AgarwalVO'NeillPJCottonBA. Prevalence and risk factors for development of delirium in burn intensive care unit patients. J Burn Care Res2010;31: 706–15.
28.
SkrobikYAhernSLeblancM. Protocolized intensive care unit management of analgesia, sedation, and delirium improves analgesia and subsyndromal delirium rates. Anesth Analg2010;111: 451–63.
29.
HoySMKeatingGM. Dexmedetomidine: a review of its use for sedation in mechanically ventilated patients in an intensive care setting and for procedural sedation. Drugs2011;71: 1481–501.
30.
AndreasenNJ. Neuropsychiatric complications in burn patients. Int J Psychiatry Med1974;5: 161–71.
31.
DyerCBAshtonCMTeasdaleTA. Postoperative delirium. A review of 80 primary data-collection studies. Arch Intern Med1995;155: 461–5.
32.
RolfsonDBMcElhaneyJERockwoodK. Incidence and risk factors for delirium and other adverse outcomes in older adults after coronary artery bypass graft surgery. Can J Cardiol1999;15: 771–6.
33.
BoorsmaMJolingKJFrijtersDH. The prevalence, incidence and risk factors for delirium in Dutch nursing homes and residential care homes. Int J Geriatr Psychiatry2012;27: 709–15.
34.
DosaDIntratorOMcNicollL. Preliminary derivation of a Nursing Home Confusion Assessment Method based on data from the Minimum Data Set. J Am Geriatr Soc2007;55: 1099–105.
35.
InouyeSKForemanMDMionLC. Nurses' recognition of delirium and its symptoms: comparison of nurse and researcher ratings. Arch Intern Med2001;161: 2467–73.
36.
LeonardMSpillerJKeenJ. Symptoms of depression and delirium assessed serially in palliative-care inpatients. Psychosomatics2009;50: 506–14.
37.
WongCLHolroyd-LeducJSimelDLStrausSE. Does this patient have delirium?: value of bedside instruments. JAMA2010;304: 779–86.
38.
TrzepaczPTMittalDTorresR. Validation of the Delirium Rating Scale-revised-98: comparison with the delirium rating scale and the cognitive test for delirium. J Neuropsychiatry Clin Neurosci2001;13: 229–42.
39.
SandsMBDantocBPHartshornA. Single Question in Delirium (SQiD): testing its efficacy against psychiatrist interview, the Confusion Assessment Method and the Memorial Delirium Assessment Scale. Palliat Med2010;24: 561–65.
40.
InouyeSKvan DyckCH. Clarifying confusion: the confusion assessment method. A new method for detection of delirium. Ann Intern Med1990;113: 941–48.
41.
LaurilaJVPitkalaKHStrandbergTETilvisRS. Confusion assessment method in the diagnostics of delirium among aged hospital patients: would it serve better in screening than as a diagnostic instrument?Int J Geriatr Psychiatry2002;17: 1112–19.
42.
Mac SweeneyRBarberVPageV. A national survey of the management of delirium in UK intensive care units. QJM2010;103: 243–51.
43.
BreitbartWRosenfeldBRothA. The Memorial Delirium Assessment Scale. J Pain Symptom Manage1997;13: 128–37.
44.
GaudreauJDGagnonPHarelF. Fast, systematic, and continuous delirium assessment in hospitalized patients: the nursing delirium screening scale. J Pain Symptom Manage2005;29: 368–75.
45.
ElyEWMargolinRFrancisJ. Evaluation of delirium in critically ill patients: validation of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Crit Care Med2001;29: 1370–9.
46.
TomasiCDGrandiCSalluhJ. Comparison of CAM-ICU and ICDSC for the detection of delirium in critically ill patients focusing on relevant clinical outcomes. J Crit Care2012;27: 212–17.
47.
NeufeldKJHayatMJCoughlinJM. Evaluation of two intensive care delirium screening tools for non-critically ill hospitalized patients. Psychosomatics2011;52: 133–40.
48.
InouyeSKBogardusSTJr.CharpentierPA. A multicomponent intervention to prevent delirium in hospitalized older patients. N Engl J Med1999;340: 669–76.
49.
MarcantonioERFlackerJMWrightRJResnickNM. Reducing delirium after hip fracture: a randomized trial. J Am Geriatr Soc2001;49: 516–22.
50.
DeschodtMBraesTFlamaingJ. Preventing delirium in older adults with recent hip fracture through multidisciplinary geriatric consultation. J Am Geriatr Soc2012;60: 733–39.
51.
FongHKSandsLPLeungJM. The role of postoperative analgesia in delirium and cognitive decline in elderly patients: a systematic review. Anesth Analg2006;102: 1255–66.
52.
SieberFEZakriyaKJGottschalkA. Sedation depth during spinal anesthesia and the development of postoperative delirium in elderly patients undergoing hip fracture repair. Mayo Clin Proc2010;85: 18–26.
53.
TuneLE. Serum anticholinergic activity levels and delirium in the elderly. Semin Clin Neuropsychiatry2000;5: 149–53.
54.
GirardTDKressJPFuchsBD. 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. Lancet2008;371: 126–34.
55.
SchweickertWDPohlmanMCPohlmanAS. Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. Lancet2009;373: 1874–82.
56.
MorrisonRSMagazinerJMcLaughlinMA. The impact of postoperative pain on outcomes following hip fracture. Pain2003;103: 303–11.
57.
PisaniMAMurphyTEAraujoKL. Benzodiazepine and opioid use and the duration of intensive care unit delirium in an older population. Crit Care Med2009;37: 177–83.
58.
LarsenKAKellySESternTA. Administration of olanzapine to prevent postoperative delirium in elderly joint-replacement patients: a randomized, controlled trial. Psychosomatics2010;51: 409–18.
59.
DevlinJWRobertsRJFongJJ. Efficacy and safety of quetiapine in critically ill patients with delirium: a prospective, multicenter, randomized, double-blind, placebo-controlled pilot study. Crit Care Med2010;38: 419–27.
60.
WangWLiHLWangDX. Haloperidol prophylaxis decreases delirium incidence in elderly patients after noncardiac surgery: a randomized controlled trial. Crit Care Med2012;40: 731–39.
61.
KalisvaartKJde JongheJFBogaardsMJ. Haloperidol prophylaxis for elderly hip-surgery patients at risk for delirium: a randomized placebo-controlled study. J Am Geriatr Soc2005;53: 1658–66.
62.
GirardTDPandharipandePPCarsonSS. Feasibility, efficacy, and safety of antipsychotics for intensive care unit delirium: the MIND randomized, placebo-controlled trial. Crit Care Med2010;38: 428–37.
63.
van EijkMMRoesKCHoningML. Effect of rivastigmine as an adjunct to usual care with haloperidol on duration of delirium and mortality in critically ill patients: a multicentre, double-blind, placebo-controlled randomised trial. Lancet2010;376: 1829–37.
64.
JacobiJFraserGLCoursinDB. Clinical practice guidelines for the sustained use of sedatives and analgesics in the critically ill adult. Crit Care Med2002;30: 119–41.
65.
HassaballaHABalkRA. Torsade de pointes associated with the administration of intravenous haloperidol: A review of the literature and practical guidelines for use. Expert Opin Drug Saf2003;2: 543–47.
66.
LonerganELuxenbergJSastreA Areosa. Benzodiazepines for delirium. Cochrane Database Syst Rev2009: CD006379.
