Advertisement

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

  • B. Rohaut
  • A. Eliseyev
  • J. ClaassenEmail author
Chapter
Part of the Annual Update in Intensive Care and Emergency Medicine book series (AUICEM)

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.

References

  1. 1.
    Owen AM, Coleman MR, Boly M, et al. Detecting awareness in the vegetative state. Science. 2006;313:1402.CrossRefGoogle Scholar
  2. 2.
    Schiff ND. Cognitive motor dissociation following severe brain injuries. JAMA Neurol. 2015;72:1413–5.CrossRefGoogle Scholar
  3. 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.CrossRefGoogle Scholar
  4. 4.
    Plum F, Posner JB. The Diagnosis of Stupor and Coma. 3rd ed. Philadelphia: Oxford University Press; 1980.Google Scholar
  5. 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.CrossRefGoogle Scholar
  6. 6.
    Giacino JT, Katz DI, Schiff ND, et al. Practice guideline update recommendations summary: disorders of consciousness. Neurology. 2018;91:450–60.CrossRefGoogle Scholar
  7. 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.CrossRefGoogle Scholar
  8. 8.
    Giacino JT, Ashwal S, Childs N, et al. The minimally conscious state: definition and diagnostic criteria. Neurology. 2002;58:349–53.CrossRefGoogle Scholar
  9. 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.CrossRefGoogle Scholar
  10. 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.CrossRefGoogle Scholar
  11. 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.CrossRefGoogle Scholar
  12. 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.CrossRefGoogle Scholar
  13. 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.CrossRefGoogle Scholar
  14. 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.CrossRefGoogle Scholar
  15. 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.CrossRefGoogle Scholar
  16. 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.CrossRefGoogle Scholar
  17. 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.CrossRefGoogle Scholar
  18. 18.
    Rohaut B, Naccache L. Disentangling conscious from unconscious cognitive processing with event-related EEG potentials. Rev Neurol (Paris). 2017;173:521–8.CrossRefGoogle Scholar
  19. 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.CrossRefGoogle Scholar
  20. 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.CrossRefGoogle Scholar
  21. 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.CrossRefGoogle Scholar
  22. 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.CrossRefGoogle Scholar
  23. 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.CrossRefGoogle Scholar
  24. 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.CrossRefGoogle Scholar
  25. 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.CrossRefGoogle Scholar
  26. 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.CrossRefGoogle Scholar
  27. 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.CrossRefGoogle Scholar
  28. 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.CrossRefGoogle Scholar
  29. 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.CrossRefGoogle Scholar
  30. 30.
    Hosker C, Ward D. Hypoactive delirium. BMJ. 2017;357:j2047.CrossRefGoogle Scholar
  31. 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.CrossRefGoogle Scholar
  32. 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.CrossRefGoogle Scholar
  33. 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.CrossRefGoogle Scholar
  34. 34.
    Carroll SM. Nonvocal ventilated patients perceptions of being understood. West J Nurs Res. 2004;26:85–103.CrossRefGoogle Scholar
  35. 35.
    Menzel LK. Factors related to the emotional responses of intubated patients to being unable to speak. Heart Lung. 1998;27:245–52.CrossRefGoogle Scholar
  36. 36.
    Daly JJ, Huggins JE. Brain-computer interface: current and emerging rehabilitation applications. Arch Phys Med Rehabil. 2015;96:S1–7.CrossRefGoogle Scholar
  37. 37.
    Chaudhary U, Birbaumer N, Curado MR. Brain-machine interface (BMI) in paralysis. Ann Phys Rehabil Med. 2015;58:9–13.CrossRefGoogle Scholar
  38. 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.CrossRefGoogle Scholar
  39. 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.CrossRefGoogle Scholar
  40. 40.
    De Massari D, Ruf CA, Furdea A, et al. Brain communication in the locked-in state. Brain. 2013;136:1989–2000.CrossRefGoogle Scholar
  41. 41.
    Pfurtscheller G, Allison BZ, Brunner C, et al. The hybrid BCI. Front Neurosci. 2010;4:30.PubMedGoogle Scholar
  42. 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.CrossRefGoogle Scholar
  43. 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.CrossRefGoogle Scholar
  44. 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.CrossRefGoogle Scholar
  45. 45.
    Fins JJ, Bernat JL. Ethical, palliative, and policy considerations in disorders of consciousness. Neurology. 2018;91:471–5.CrossRefGoogle Scholar
  46. 46.
    Fins JJ. Constructing an ethical stereotaxy for severe brain injury: balancing risks, benefits and access. Nat Rev Neurosci. 2003;4:323–7.CrossRefGoogle Scholar
  47. 47.
    Jennett B, Plum F. Persistent vegetative state after brain damage. A syndrome in search of a name. Lancet. 1972;1:734–7.CrossRefGoogle Scholar
  48. 48.
    Bayne T, Hohwy J, Owen AM. Reforming the taxonomy in disorders of consciousness. Ann Neurol. 2017;82:866–72.CrossRefGoogle Scholar
  49. 49.
    Bernat JL. Nosologic considerations in disorders of consciousness. Ann Neurol. 2017;82:863–5.CrossRefGoogle Scholar
  50. 50.
    Naccache L. Minimally conscious state or cortically mediated state? Brain. 2018;141:949–60.CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Neurocritical Care, Department of NeurologyColumbia UniversityNew YorkUSA

Personalised recommendations