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Uncovering Consciousness in Unresponsive ICU Patients: Technical, Medical and Ethical Considerations

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Annual Update in Intensive Care and Emergency Medicine 2019

Part of the book series: Annual Update in Intensive Care and Emergency Medicine ((AUICEM))

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Abstract

Over a decade ago, researchers published the first case of a patient who had been clinically unresponsive for years after traumatic brain injury (TBI) and demonstrated command following using motor imagery paradigms visualized by functional magnetic resonance imaging (fMRI) [1]. The term “cognitive motor dissociation” is gaining popularity to describe this scenario of an inability to behaviorally express preserved cognitive processes [2]. Alternative labels are covert or hidden consciousness and functional locked-in syndrome [3] (see Table 34.1). A flurry of subsequent studies using fMRI and functional electroencephalogram (fEEG) approaches explored the boundaries of human consciousness following brain injury. This growing body of knowledge is now being discussed in the lay press and is starting to affect clinical medicine, challenging the classical taxonomy of disorders of consciousness ([4] see Table 34.1). Until very recently, researchers have focused their attention on patients suffering from chronic disorders of consciousness and have generated estimates of cognitive motor dissociation of around 15% using convenience samples of these patients [5]. Detection of cognitive motor dissociation in the acute phase of brain injury may have prognostic significance as these patients are more likely to also recover behavioral command following and have better long-term functional outcomes.

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References

  1. Owen AM, Coleman MR, Boly M, et al. Detecting awareness in the vegetative state. Science. 2006;313:1402.

    Article  CAS  Google Scholar 

  2. Schiff ND. Cognitive motor dissociation following severe brain injuries. JAMA Neurol. 2015;72:1413–5.

    Article  Google Scholar 

  3. Bruno MA, Vanhaudenhuyse A, Thibaut A, et al. From unresponsive wakefulness to minimally conscious PLUS and functional locked-in syndromes: recent advances in our understanding of disorders of consciousness. J Neurol. 2011;258:1373–84.

    Article  Google Scholar 

  4. Plum F, Posner JB. The Diagnosis of Stupor and Coma. 3rd ed. Philadelphia: Oxford University Press; 1980.

    Google Scholar 

  5. Kondziella D, Friberg CK, Frokjaer VG, et al. Preserved consciousness in vegetative and minimal conscious states: systematic review and meta-analysis. J Neurol Neurosurg Psychiatry. 2016;87:485–92.

    Article  Google Scholar 

  6. Giacino JT, Katz DI, Schiff ND, et al. Practice guideline update recommendations summary: disorders of consciousness. Neurology. 2018;91:450–60.

    Article  Google Scholar 

  7. Wijdicks EFM, Kramer AA, Rohs T, et al. Comparison of the full outline of unresponsiveness score and the Glasgow coma scale in predicting mortality in critically ill patients. Crit Care Med. 2015;43:439–44.

    Article  Google Scholar 

  8. Giacino JT, Ashwal S, Childs N, et al. The minimally conscious state: definition and diagnostic criteria. Neurology. 2002;58:349–53.

    Article  Google Scholar 

  9. Laureys S, Celesia GG, Cohadon F, et al. Unresponsive wakefulness syndrome: a new name for the vegetative state or apallic syndrome. BMC Med. 2010;8:68.

    Article  Google Scholar 

  10. Stender J, Gosseries O, Bruno MA, et al. Diagnostic precision of PET imaging and functional MRI in disorders of consciousness: a clinical validation study. Lancet. 2014;384:514–22.

    Article  Google Scholar 

  11. Liu AA, Voss HU, Dyke JP, et al. Arterial spin labeling and altered cerebral blood flow patterns in the minimally conscious state. Neurology. 2011;77:1518–23.

    Article  CAS  Google Scholar 

  12. King JR, Sitt JD, Faugeras F, et al. Information sharing in the brain indexes consciousness in noncommunicative patients. Curr Biol. 2013;23:1914–9.

    Article  CAS  Google Scholar 

  13. Chennu S, Annen J, Wannez S, et al. Brain networks predict metabolism, diagnosis and prognosis at the bedside in disorders of consciousness. Brain. 2017;140:2120–32.

    Article  Google Scholar 

  14. Demertzi A, Antonopoulos G, Heine L, et al. Intrinsic functional connectivity differentiates minimally conscious from unresponsive patients. Brain. 2015;138(Pt 9):2619–3.

    Article  Google Scholar 

  15. Sitt JD, King JR, El Karoui I, et al. Large scale screening of neural signatures of consciousness in patients in a vegetative or minimally conscious state. Brain. 2014;137:2258–70.

    Article  Google Scholar 

  16. Claassen J, Velazquez A, Meyers E, et al. Bedside quantitative electroencephalography improves assessment of consciousness in comatose subarachnoid hemorrhage patients. Ann Neurol. 2016;80:541–53.

    Article  Google Scholar 

  17. Bekinschtein TA, Dehaene S, Rohaut B, et al. Neural signature of the conscious processing of auditory regularities. Proc Natl Acad Sci U S A. 2009;106:1672–7.

    Article  CAS  Google Scholar 

  18. Rohaut B, Naccache L. Disentangling conscious from unconscious cognitive processing with event-related EEG potentials. Rev Neurol (Paris). 2017;173:521–8.

    Article  CAS  Google Scholar 

  19. Casali AG, Gosseries O, Rosanova M, et al. A theoretically based index of consciousness independent of sensory processing and behavior. Sci Transl Med. 2013;5:198ra105.

    Article  Google Scholar 

  20. Casarotto S, Comanducci A, Rosanova M, et al. Stratification of unresponsive patients by an independently validated index of brain complexity. Ann Neurol. 2016;80:718–29.

    Article  Google Scholar 

  21. Zandbergen EGJ, Koelman JHTM, Haan RJ, et al. SSEPs and prognosis in postanoxic coma only short or also long latency responses. Neurology. 2006;67:583–6.

    Article  CAS  Google Scholar 

  22. Monti MM, Vanhaudenhuyse A, Coleman MR, et al. Willful modulation of brain activity in disorders of consciousness. N Engl J Med. 2010;362:579–89.

    Article  CAS  Google Scholar 

  23. Cruse D, Chennu S, Chatelle C, et al. Bedside detection of awareness in the vegetative state: a cohort study. Lancet. 2011;378:2088–94.

    Article  Google Scholar 

  24. Goldfine AM, Victor JD, Conte MM, et al. Determination of awareness in patients with severe brain injury using EEG power spectral analysis. Clin Neurophysiol. 2011;122:2157–68.

    Article  Google Scholar 

  25. Cruse D, Chennu S, Chatelle C, et al. Relationship between etiology and covert cognition in the minimally conscious state. Neurology. 2012;78:816–22.

    Article  CAS  Google Scholar 

  26. Edlow BL, Chatelle C, Spencer CA, et al. Early detection of consciousness in patients with acute severe traumatic brain injury. Brain. 2017;140:2399–414.

    Article  Google Scholar 

  27. Curley WH, Forgacs PB, Voss HU, et al. Characterization of EEG signals revealing covert cognition in the injured brain. Brain. 2018;141:1404–21.

    Article  Google Scholar 

  28. Radek L, Kallionpää RE, Karvonen M, et al. Dreaming and awareness during dexmedetomidine- and propofol-induced unresponsiveness. Br J Anaesth. 2018;121:260–9.

    Article  CAS  Google Scholar 

  29. Salluh JI, Wang H, Schneider EB, et al. Outcome of delirium in critically ill patients: systematic review and meta-analysis. BMJ. 2015;350:h2538.

    Article  Google Scholar 

  30. Hosker C, Ward D. Hypoactive delirium. BMJ. 2017;357:j2047.

    Article  Google Scholar 

  31. Harvey D, Butler J, Groves J, et al. Management of perceived devastating brain injury after hospital admission: a consensus statement from stakeholder professional organizations. Br J Anaesth. 2018;120:138–45.

    Article  CAS  Google Scholar 

  32. Rohaut B, Claassen J. Decision making in perceived devastating brain injury: a call to explore the impact of cognitive biases. Br J Anaesth. 2018;120:5–9.

    Article  CAS  Google Scholar 

  33. Happ MB, Garrett K, Thomas DD, et al. Nurse-patient communication interactions in the intensive care unit. Am J Crit Care. 2011;20:e28–40.

    Article  Google Scholar 

  34. Carroll SM. Nonvocal ventilated patients perceptions of being understood. West J Nurs Res. 2004;26:85–103.

    Article  Google Scholar 

  35. Menzel LK. Factors related to the emotional responses of intubated patients to being unable to speak. Heart Lung. 1998;27:245–52.

    Article  CAS  Google Scholar 

  36. Daly JJ, Huggins JE. Brain-computer interface: current and emerging rehabilitation applications. Arch Phys Med Rehabil. 2015;96:S1–7.

    Article  Google Scholar 

  37. Chaudhary U, Birbaumer N, Curado MR. Brain-machine interface (BMI) in paralysis. Ann Phys Rehabil Med. 2015;58:9–13.

    Article  CAS  Google Scholar 

  38. Dehzangi O, Farooq M. Portable brain-computer interface for the intensive care unit patient communication using subject-dependent SSVEP identification. Biomed Res Int. 2018;2018:9796238.

    Article  Google Scholar 

  39. Chatelle C, Spencer CA, Cash SS, et al. Feasibility of an EEG-based brain-computer interface in the intensive care unit. Clin Neurophysiol. 2018;129:1519–25.

    Article  Google Scholar 

  40. De Massari D, Ruf CA, Furdea A, et al. Brain communication in the locked-in state. Brain. 2013;136:1989–2000.

    Article  Google Scholar 

  41. Pfurtscheller G, Allison BZ, Brunner C, et al. The hybrid BCI. Front Neurosci. 2010;4:30.

    PubMed  Google Scholar 

  42. Hong KS, Khan MJ. Hybrid brain-computer interface techniques for improved classification accuracy and increased number of commands: a review. Front Neurorobot. 2017;11:35.

    Article  Google Scholar 

  43. Eliseyev A, Auboiroux V, Costecalde T, et al. Recursive exponentially weighted n-way partial least squares regression with recursive-validation of hyper-parameters in brain-computer interface applications. Sci Rep. 2017;7:16281.

    Article  Google Scholar 

  44. Turgeon AF, Lauzier F, Simard JF, et al. Mortality associated with withdrawal of life-sustaining therapy for patients with severe traumatic brain injury: a Canadian multicentre cohort study. CMAJ. 2011;183:1581–8.

    Article  Google Scholar 

  45. Fins JJ, Bernat JL. Ethical, palliative, and policy considerations in disorders of consciousness. Neurology. 2018;91:471–5.

    Article  Google Scholar 

  46. Fins JJ. Constructing an ethical stereotaxy for severe brain injury: balancing risks, benefits and access. Nat Rev Neurosci. 2003;4:323–7.

    Article  CAS  Google Scholar 

  47. Jennett B, Plum F. Persistent vegetative state after brain damage. A syndrome in search of a name. Lancet. 1972;1:734–7.

    Article  CAS  Google Scholar 

  48. Bayne T, Hohwy J, Owen AM. Reforming the taxonomy in disorders of consciousness. Ann Neurol. 2017;82:866–72.

    Article  Google Scholar 

  49. Bernat JL. Nosologic considerations in disorders of consciousness. Ann Neurol. 2017;82:863–5.

    Article  Google Scholar 

  50. Naccache L. Minimally conscious state or cortically mediated state? Brain. 2018;141:949–60.

    Article  Google Scholar 

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Authors and Affiliations

  1. Neurocritical Care, Department of Neurology, Columbia University, New York, NY, USA

    B. Rohaut, A. Eliseyev & J. Claassen

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  1. B. Rohaut
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  2. A. Eliseyev
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  3. J. Claassen
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Correspondence to J. Claassen .

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Editors and Affiliations

  1. Dept. of Intensive Care, Erasme Hospital, Université libre de Bruxelles, Brussels, Belgium

    Jean-Louis Vincent

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Rohaut, B., Eliseyev, A., Claassen, J. (2019). Uncovering Consciousness in Unresponsive ICU Patients: Technical, Medical and Ethical Considerations. In: Vincent, JL. (eds) Annual Update in Intensive Care and Emergency Medicine 2019. Annual Update in Intensive Care and Emergency Medicine. Springer, Cham. https://doi.org/10.1007/978-3-030-06067-1_34

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  • DOI: https://doi.org/10.1007/978-3-030-06067-1_34

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  • Online ISBN: 978-3-030-06067-1

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