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Memory in relation to depth of sedation in adult mechanically ventilated intensive care patients

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Abstract

Objective

To investigate the relationship between memory and intensive care sedation.

Design and setting

Prospective cohort study over 18 months in two general intensive care units (ICUs) in district university hospitals.

Patients

313 intubated mechanically ventilated adults admitted for more than 24 h, 250 of whom completed the study.

Measurements

Patients (n = 250) were interviewed in the ward 5 days after discharge from the ICU using the ICU Memory Tool. Patient characteristics, doses of sedative and analgesic agents, and sedation scores as measured by the Motor Activity Assessment Scale (MAAS) were collected from hospital records after the interview.

Results

Patients with no recall (18%) were significantly older, had higher baseline severity of illness, and experienced fewer periods of wakefulness (median proportion of MAAS score 3; 0.37 vs. 0.70) than those who had memories of the ICU (82%). Multivariate analyses showed that increasing proportion of MAAS 0–2 and older age were significantly associated with having no recall. Patients with delusional memories (34%) had significantly longer ICU stay (median 6.6 vs. 2.2 days), higher baseline severity of illness, higher proportions of MAAS scores 4–6, and more administration of midazolam than those with recall of the ICU without delusional memories.

Conclusions

Heavy sedation increases the risk of having no recall, and longer ICU stay increases the risk of delusional memories. The depth of sedation during total ICU stay as recorded with the MAAS may predict the probability of having memories of the ICU.

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References

  1. Capuzzo M, Valpondi V, Cingolani E, De Luca S, Gianstefani G, Grassi L, Alvisi R (2004) Application of the Italian version of the intensive care unit Memory tool in the clinical setting. Crit Care 8:R48–R55

    Article  PubMed  Google Scholar 

  2. Leur JP van de, van der Schans CP, Loef BG, Deelman BG, Geertzen JH, Zwaveling JH (2004) Discomfort and factual recollection in intensive care unit patients. Crit Care 8:R467–R473

    Article  PubMed  Google Scholar 

  3. Griffiths RD, Jones C (2001) Filling the intensive care memory gap? Intensive Care Med 27:344–346

    Article  PubMed  CAS  Google Scholar 

  4. Jones C (2002) Acute psychological problems. In: Griffiths RD, Jones C (ed) Intensive care aftercare. Butterworth-Heinemann, Oxford, pp 19–26

  5. Skirrow P (2002) Delusional memories of ICU. In: Griffiths RD, Jones C (ed) Intensive care aftercare. Butterworth-Heinemann, Oxford, pp 28–35

  6. Hupcey JE, Zimmerman HE (2000) The need to know: experiences of critically ill patients. Am J Crit Care 9:192–198

    PubMed  CAS  Google Scholar 

  7. Jones C, Griffiths RD, Humphris G, Skirrow PM (2001) Memory, delusions, and the development of acute posttraumatic stress disorder-related symptoms after intensive care. Crit Care Med 29:573–580

    Article  PubMed  CAS  Google Scholar 

  8. Rattray J, Johnston M, Wildsmith JA (2005) Predictors of emotional outcomes of intensive care. Anaesthesia 60:1085–1092

    Article  PubMed  CAS  Google Scholar 

  9. Schelling G, Stoll C, Haller M, Briegel J, Manert W, Hummel T, Lenhart A, Heyduck M, Polasek J, Meier M, Preuss U, Bullinger M, Schuffel W, Peter K (1998) Health-related quality of life and posttraumatic stress disorder in survivors of the acute respiratory distress syndrome. Crit Care Med 26:651–659

    Article  PubMed  CAS  Google Scholar 

  10. Granja C, Lopes A, Moreira S, Dias C, Costa-Pereira A, Carneiro A (2005) Patients' recollections of experiences in the intensive care unit may affect their quality of life. Crit Care 9:R96–R109

    Article  PubMed  Google Scholar 

  11. Hough CL, Curtis JR (2005) Long-term sequelae of critical illness: memories and health-related quality of life. Crit Care 9:145–146

    Article  PubMed  Google Scholar 

  12. Rotondi AJ, Chelluri L, Sirio C, Mendelsohn A, Schulz R, Belle S, Im K, Donahoe M, Pinsky MR (2002) Patients' recollections of stressful experiences while receiving prolonged mechanical ventilation in an intensive care unit. Crit Care Med 30:746–752

    Article  PubMed  Google Scholar 

  13. Burchardi H (2004) Aims of sedation/analgesia. Minerva Anestesiol 70:137–143

    PubMed  CAS  Google Scholar 

  14. Walder B, Tramer MR (2004) Analgesia and sedation in critically ill patients. Swiss Med Wkly 134:333–346

    PubMed  Google Scholar 

  15. Jones C, Griffiths RD, Humphris G (2000) Disturbed memory and amnesia related to intensive care. Memory 8:79–94

    Article  PubMed  CAS  Google Scholar 

  16. McGaugh JL, Cahill L (1997) Interaction of neuromodulatory systems in modulating memory storage. Behav Brain Res 83:31–38

    Article  PubMed  CAS  Google Scholar 

  17. Kolk BA van der (1996) Trauma and memory. In: McFarlane AC, van der Kolk BA, Weisaeth L (ed) Traumatic stress: the effects of overwhelming experience on mind, body, and society. Guilford, New York, pp 279–302

  18. Wagner BK, O'Hara DA, Hammond JS (1997) Drugs for amnesia in the ICU. Am J Crit Care 6:192–201

    PubMed  CAS  Google Scholar 

  19. Clifford JO, Buchman TG (2002) Sedation modulates recognition of novel stimuli and adaptation to regular stimuli in critically ill adults. Crit Care Med 30:609–616

    Article  PubMed  Google Scholar 

  20. Veselis RA, Reinsel RA, Feshchenko VA, Johnson R (2004) Information loss over time defines the memory defect of propofol: a comparative response with thiopental and dexmedetomidine. Anesthesiology 101:831–841

    Article  PubMed  CAS  Google Scholar 

  21. Capuzzo M, Pinamonti A, Cingolani E, Grassi L, Bianconi M, Contu P, Gritti G, Alvisi R (2001) Analgesia, sedation, and memory of intensive care. J Crit Care 16:83–89

    Article  PubMed  CAS  Google Scholar 

  22. Rundshagen I, Schnabel K, Wegner C, Schulte am Esch S (2002) Incidence of recall, nightmares, and hallucinations during analgosedation in intensive care. Intensive Care Med 28:38–43

    Article  PubMed  CAS  Google Scholar 

  23. Young C, Knudsen N, Hilton A, Reves JG (2000) Sedation in the intensive care unit. Crit Care Med 28:854–866

    Article  PubMed  CAS  Google Scholar 

  24. Samuelson KA, Lundberg D, Fridlund B (2005) Memory in relation to intensive care sedation. Intensive Care Med 31 [Suppl 1]:S12

  25. Brook AD, Ahrens TS, Schaiff R, Prentice D, Sherman G, Shannon W, Kollef MH (1999) Effect of a nursing-implemented sedation protocol on the duration of mechanical ventilation. Crit Care Med 27:2609–2615

    Article  PubMed  CAS  Google Scholar 

  26. Kress JP, Pohlman AS, O'Connor MF, Hall JB (2000) Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med 342:1471–1477

    Article  PubMed  CAS  Google Scholar 

  27. Knaus WA, Draper EA, Wagner DP, Zimmerman JE (1985) APACHE II: a severity of disease classification system. Crit Care Med 13:818–829

    Article  PubMed  CAS  Google Scholar 

  28. Devlin JW, Boleski G, Mlynarek M, Nerenz DR, Peterson E, Jankowski M, Horst HM, Zarowitz BJ (1999) Motor Activity Assessment Scale: a valid and reliable sedation scale for use with mechanically ventilated patients in an adult surgical intensive care unit. Crit Care Med 27:1271–1275

    Article  PubMed  CAS  Google Scholar 

  29. Jones C, Humphris G, Griffiths R (2000) Preliminary validation of the ICUM tool: a tool for assessing memory of the intensive care experience. Clin Intensive Care 11:251–255

    Article  Google Scholar 

  30. 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 286:2703–2710

    Article  PubMed  CAS  Google Scholar 

  31. Altman DG (1991) Practical statistics for medical research. Chapman and Hall, London

  32. Hosmer DW, Lemeshow S (2000) Applied logistic regression. Wiley, New York

  33. Russell S (1999) An exploratory study of patients' perceptions, memories and experiences of an intensive care unit. J Adv Nurs 29:783–791

    Article  PubMed  CAS  Google Scholar 

  34. Bion JF, Logan BK, Newman PM, Brodie MJ, Oliver JS, Aitchison TC, Ledingham IM (1986) Sedation in intensive care: morphine and renal function. Intensive Care Med 12:359–365

    Article  PubMed  CAS  Google Scholar 

  35. Devlin JW, Fraser GL, Kanji S, Riker RR (2001) Sedation assessment in critically ill adults. Ann Pharmacother 35:1624–1632

    Article  PubMed  CAS  Google Scholar 

  36. 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 30:119–141

    Article  PubMed  Google Scholar 

  37. Watson BD, Kane-Gill SL (2004) Sedation assessment in critically ill adults: 2001–2004 update. Ann Pharmacother 38:1898–1906

    Article  PubMed  Google Scholar 

  38. Roberts B, Chaboyer W (2004) Patients' dreams and unreal experiences following intensive care unit admission. Nurs Crit Care 9:173–180

    Article  PubMed  Google Scholar 

  39. Kollef MH, Levy NT, Ahrens TS, Schaiff R, Prentice D, Sherman G (1998) The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation. Chest 114:541–548

    Article  PubMed  CAS  Google Scholar 

  40. Cammarano WB, Pittet JF, Weitz S, Schlobohm RM, Marks JD (1998) Acute withdrawal syndrome related to the administration of analgesic and sedative medications in adult intensive care unit patients. Crit Care Med 26:676–684

    Article  PubMed  CAS  Google Scholar 

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Authors and Affiliations

  1. Division of Nursing, Lund University, Department of Health Sciences, Box 157, 22100, Lund, Sweden

    Karin Samuelson & Bengt Fridlund

  2. Division of Anesthesiology and Intensive Care, Lund University Hospital, Department of Clinical Sciences, 22100, Lund, Sweden

    Dag Lundberg

Authors
  1. Karin Samuelson
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  2. Dag Lundberg
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  3. Bengt Fridlund
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Correspondence to Karin Samuelson.

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Samuelson, K., Lundberg, D. & Fridlund, B. Memory in relation to depth of sedation in adult mechanically ventilated intensive care patients. Intensive Care Med 32, 660–667 (2006). https://doi.org/10.1007/s00134-006-0105-x

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  • DOI: https://doi.org/10.1007/s00134-006-0105-x

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