Intensive Care Medicine

, Volume 33, Issue 6, pp 929–940 | Cite as

Delirium assessment in the critically ill

  • John W. Devlin
  • Jeffrey J. Fong
  • Gilles L. Fraser
  • Richard R. Riker
Review

Abstract

Objective

To compare available instruments for assessing delirium in critically ill adults that have undergone validity testing and provide clinicians with strategies to incorporate these instruments into clinical practice.

Design

Medline (1966–September 2006) was searched using the key words: delirium, cognitive dysfunction, assessment, intensive care unit, and critical illness to identify assessment tools that have been used to evaluate delirium in critically ill adults. A special emphasis was placed on delirium assessment tools that have been properly validated. Data on how these tools have been adopted into clinical practice as well as strategies for clinicians to improve delirium assessment in the ICU are highlighted.

Measurements and results

Six delirium assessment instruments including the Cognitive Test for Delirium (CTD), abbreviated CTD, Confusion Assessment Method–ICU, Intensive Care Delirium Screening Checklist, NEECHAM scale, and the Delirium Detection Score were identified. While each of these scales have undergone validation in critically ill adults, substantial differences exist among the scales in terms of the quality and extent of the validation effort, the specific components of the delirium syndrome each address, their ability to identify hypoactive delirium, their use in patients with a compromised level of consciousness, and their ease of use.

Conclusions

Incorporation of delirium assessment into clinical practice in the intensive care unit using a validated tool may improve patient care. Clinicians can adopt a number of different strategies to overcome the many barriers associated with routine delirium assessment in the ICU.

Keywords

Assessment Delirium Critical illness Intensive care unit Nursing Score 

References

  1. 1.
    Ely EW, Gautam S, Margolin R, Francis J, May L, Speroff T, Truman B, Dittus R, Bernard GR, Inouye SK (2001) The impact of delirium in the intensive care unit on hospital length of stay. Intensive Care Med 27:1892–1900PubMedCrossRefGoogle Scholar
  2. 2.
    Ely EW, Shintani A, Truman B, Speroff T, Gordon SM, Harrell FE Jr, Inouye SK, Bernard GR, Dittus RS (2004) Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit. JAMA 291:1753–1762PubMedCrossRefGoogle Scholar
  3. 3.
    Inouye SK (1994) The dilemma of delirium: clinical and research controversies regarding diagnosis and evaluation of delirium in hospitalized elderly medical patients. Am J Med 97:278–288PubMedCrossRefGoogle Scholar
  4. 4.
    Lin SM, Liu CY, Wang CH, Lin HC, Huang CD, Huang PY, Fang YF, Shieh MH, Kuo HP (2004) The impact of delirium on the survival of mechanically ventilated patients. Crit Care Med 32:2254–2259PubMedCrossRefGoogle Scholar
  5. 5.
    Milbrandt EB, Deppen S, Harrison PL, Shintani AK, Speroff T, Stiles RA, Truman B, Bernard GR, Dittus RS, Ely EW (2004) Costs associated with delirium in mechanically ventilated patients. Crit Care Med 32:955–962PubMedCrossRefGoogle Scholar
  6. 6.
    O'Keeffe S, Lavan J (1997) The prognostic significance of delirium in older hospital patients. J Am Geriatr Soc 45:174–178PubMedGoogle Scholar
  7. 7.
    Bowton DL (2004) Delirium-the cost of inattention. Crit Care Med 32:1080–1081PubMedCrossRefGoogle Scholar
  8. 8.
    Thomason JW, Shintani A, Peterson JF, Pun BT, Jackson JC, Ely EW (2005) Intensive care unit delirium is an independent predictor of longer hospital stay: a prospective analysis of 261 non-ventilated patients. Crit Care 9:R375–R381PubMedCrossRefGoogle Scholar
  9. 9.
    Andrew MK, Freter SH, Rockwood K (2005) Incomplete functional recovery after delirium in elderly people: a prospective cohort study. BMC Geriatr 5:5PubMedCrossRefGoogle Scholar
  10. 10.
    Levkoff SE, Evans DA, Liptzin B, Cleary PD, Lipsitz LA, Wetle TT, Reilly CH, Pilgrim DM, Schor J, Rowe J (1992) Delirium. The occurrence and persistence of symptoms among elderly hospitalized patients. Arch Intern Med 152:334–340PubMedCrossRefGoogle Scholar
  11. 11.
    McNicoll L, Pisani MA, Zhang Y, Ely EW, Siegel MD, Inouye SK (2003) Delirium in the intensive care unit: occurrence and clinical course in older patients. J Am Geriatr Soc 51:591–598PubMedCrossRefGoogle Scholar
  12. 12.
    Burns A, Gallagley A, Byrne J (2004) Delirium. J Neurol Neurosurg Psychiatry 75:362–367PubMedCrossRefGoogle Scholar
  13. 13.
    Justic M (2000) Does “ICU psychosis” really exist? Crit Care Nurse 20:28–37PubMedGoogle Scholar
  14. 14.
    Dubois MJ, Bergeron N, Dumont M, Dial S, Skrobik Y (2001) Delirium in an intensive care unit: a study of risk factors. Intensive Care Med. 27:1297–1304PubMedCrossRefGoogle Scholar
  15. 15.
    Pandharipande P, Jackson J, Ely EW (2005) Delirium: acute cognitive dysfunction in the critically ill. Curr Opin Crit Care 11:360–368PubMedCrossRefGoogle Scholar
  16. 16.
    McGuire BE, Basten CJ, Ryan CJ, Gallagher J (2001) Intensive care unit syndrome: a dangerous misnomer. Arch Intern Med 160:906–909CrossRefGoogle Scholar
  17. 17.
    Pisani MA, McNicoll L, Inouye SK (2003) Cognitive impairment in the intensive care unit. Clin Chest Med 24:727–737PubMedCrossRefGoogle Scholar
  18. 18.
    Bergeron N, Skrobik Y, Dubois MJ (2002) Delirium in critically ill patients. Crit Care 6:181–182PubMedCrossRefGoogle Scholar
  19. 19.
    McNicoll L, Pisani MA, Ely EW, Gifford D, Inouye SK (2005) Detection of delirium in the intensive care unit: comparison of confusion assessment method for the intensive care unit with confusion assessment method ratings. J Am Geriatr Soc 53:495–500PubMedCrossRefGoogle Scholar
  20. 20.
    Bergeron N, Skrobik Y, Dubois MJ (2005) Is disturbance of consciousness an important feature of ICU delirium? Intensive Care Med 31:887PubMedCrossRefGoogle Scholar
  21. 21.
    Skrobik Y (2003) An overview of delirium in the critical care setting. Geriatr Aging 6:30–35Google Scholar
  22. 22.
    Jacobi J, Fraser GL, Coursin DB, Riker RR, Fontaine D, Wittbrodt ET, Chalfin DB, Masica MF, Bjerke HS, Coplin WM, Crippen DW, Fuchs BD, Kelleher RM, Marik PE, Nasraway SA, Murray MJ, Peruzzi WT, Lumb PD (2002) Clinical practice guidelines for the sustained use of sedatives and analgesics in the critically ill adult. Crit Care Med 30:119–141PubMedCrossRefGoogle Scholar
  23. 23.
    Ely EW, Stephens RK, Jackson JC, Thomason JW, Truman B, Gordon S, Dittus RS, Bernard GR (2004) Current opinions regarding the importance, diagnosis, and management of delirium in the intensive care unit: a survey of 912 healthcare professionals. Crit Care Med 32:106–112PubMedCrossRefGoogle Scholar
  24. 24.
    Lundstrom M, Edlund A, Karlsson S, Brannstrom B, Bucht G, Gustafson Y (2005) A multifactorial intervention program reduces the duration of delirium, length of hospitalization, and mortality in delirious patients. J Am Geriatr Soc 53:622–628PubMedCrossRefGoogle Scholar
  25. 25.
    Anonymous (2000) Diagnostic and statistical manual of mental disorders–text revision. American Psychiatric Association, WashingtonGoogle Scholar
  26. 26.
    Ely EW, Inouye SK, Bernard GR, Gordon S, Francis J, May L, Truman B, Speroff T, Gautam S, Margolin R, Hart RP, Dittus R (2001) Delirium in mechanically ventilated patients: validity and reliability of the confusion assessment method for the intensive care unit (CAM-ICU). JAMA 286:2703–2710PubMedCrossRefGoogle Scholar
  27. 27.
    Peterson JF, Pun BT, Dittus RS, Thomason JW, Jackson JC, Shintani AK, Ely EW (2006) Delirium and its motoric subtypes: a study of 614 critically ill patients. J Am Geriatr Soc 54:479–484PubMedCrossRefGoogle Scholar
  28. 28.
    Armstrong SC, Cozza KL, Watanabe KS (1997) The misdiagnosis of delirium. Psychosomatics 38:433–439PubMedGoogle Scholar
  29. 29.
    Inouye SK, van Dyck CH, Alessi CA, Balkin S, Siegal AP, Horwitz RI (1990) Clarifying confusion: the confusion assessment method. A new method for detection of delirium. Ann Intern Med 113:941–948PubMedGoogle Scholar
  30. 30.
    Trzepacz PT, Baker RW, Greenhouse J (1988) A symptom rating scale for delirium. Psychiatry Res 23:89–97PubMedCrossRefGoogle Scholar
  31. 31.
    Breitbart W, Rosenfeld B, Roth A, Smith MJ, Cohen K, Passik S (1997) The Memorial Delirium Assessment Scale. J Pain Symptom Manage 13:128–137PubMedCrossRefGoogle Scholar
  32. 32.
    Bergeron N, Dubois MJ, Dumont M, Dial S, Skrobik Y (2001) Intensive Care Delirium Screening Checklist: evaluation of a new screening tool. Intensive Care Med 27:859–864PubMedCrossRefGoogle Scholar
  33. 33.
    Ely EW, Margolin R, Francis J, May L, Truman B, Dittus R, Speroff T, Gautam S, Bernard GR, Inouye SK (2001) Evaluation of delirium in critically ill patients: validation of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Crit Care Med 29:1370–1379PubMedCrossRefGoogle Scholar
  34. 34.
    Hart RP, Levenson JL, Sessler CN, Best AM, Schwartz SM, Rutherford LE (1996) Validation of a cognitive test for delirium in medical ICU patients. Psychosomatics 37:533–546PubMedGoogle Scholar
  35. 35.
    Hart RP, Best AM, Sessler CN, Levenson JL (1997) Abbreviated cognitive test for delirium. J Psychosom Res 43:417–423PubMedCrossRefGoogle Scholar
  36. 36.
    Csokasy J (1999) Assessment of acute confusion: use of the NEECHAM Confusion Scale. Appl Nurs Res 12:51–55PubMedCrossRefGoogle Scholar
  37. 37.
    Immers HE, Schuurmans MJ, van de Bijl JJ (2005) Recognition of delirium in ICU patients: a diagnostic study of the NEECHAM confusion scale in ICU patients. BMC Nurs 4:7PubMedCrossRefGoogle Scholar
  38. 38.
    Otter H, Martin J, Basell K, von Heymann C, Hein OV, Bollert P, Jansch P, Behnisch I, Wernecke KD, Konertz W, Loening S, Blohmer JU, Spies C (2005) Validity and reliability of the DDS for severity of delirium in the ICU. Neurocrit Care 2:150–158PubMedCrossRefGoogle Scholar
  39. 39.
    Smith MJ, Breitbart WS, Platt MM (1995) A critique of instruments and methods to detect, diagnose, and rate delirium. J Pain Symptom Manage 10:35–77PubMedCrossRefGoogle Scholar
  40. 40.
    Pun BT, Gordon SM, Peterson JF, Shintani AK, Jackson JC, Foss J, Bernard GR, Dittus RS, Ely EW (2005) Large-scale implementation of sedation and delirium monitoring in the intensive care unit: a report from two medical centers. Crit Care Med 33:1199–1205PubMedCrossRefGoogle Scholar
  41. 41.
    Roberts B, Rickard C, Rajbhandari D, Turner G, Clarke J, Hill D, Tauschke C, Chaboyer W, Parsons R (2005) Multicentre study of delirium in ICU patients using a simple screening tool. Aust Crit Care 8:6–15CrossRefGoogle Scholar
  42. 42.
    Micek ST, Anand NJ, Laible BR, Shannon WD, Kollef MH (2005) Delirium as detected by the CAM-ICU predicts restraint use among mechanically ventilated medical patients. Crit Care Med 33:1260–1265PubMedCrossRefGoogle Scholar
  43. 43.
    Devlin JW, Tanios MA, Epstein SK (2006) Intensive care unit sedation: waking up clinicians to the gap between research and practice. Crit Care Med 34:556–557PubMedCrossRefGoogle Scholar
  44. 44.
    Inouye SK, Foreman MD, Mion LC, Katz KH, Cooney LM Jr (2001) Nurses' recognition of delirium and its symptoms: comparison of nurse and researcher ratings. Arch Intern Med 161:2467–2473PubMedCrossRefGoogle Scholar
  45. 45.
    Hammond JJ (2001) Protocols and guidelines in critical care: development and implementation. Curr Opin Crit Care 7:464–468PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • John W. Devlin
    • 1
    • 2
  • Jeffrey J. Fong
    • 1
    • 2
  • Gilles L. Fraser
    • 3
  • Richard R. Riker
    • 3
  1. 1.Northeastern University School of PharmacyBostonUSA
  2. 2.Tufts-New England Medical CenterBostonUSA
  3. 3.Department of Critical Care MedicineMaine Medical CenterPortlandUSA

Personalised recommendations