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Functional coma.

L Ludwig1, L McWhirter2, S Williams2

  • 1Departments of Clinical Neurosciences and of Rehabilitation Medicine, NHS Lothian and Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.

Handbook of Clinical Neurology
|October 11, 2016
PubMed
Summary
This summary is machine-generated.

Functional coma, a rare condition of prolonged unresponsiveness, can be diagnosed by specific physical signs. These signs differentiate it from other causes of unresponsiveness, aiding accurate diagnosis.

Keywords:
catatoniacomaconversion disorderfactitiousfunctional neurologic disorderpsychogenicstuporunconsciousness

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Area of Science:

  • Neurology
  • Psychiatry
  • Disorders of Consciousness

Background:

  • Functional coma is a rare condition characterized by prolonged motionless dissociative attacks with reduced responsiveness.
  • It is often confused with other conditions like depressive stupor, catatonia, and nonepileptic seizures.
  • Psychological factors are key to understanding the etiology of functional coma.

Purpose of the Study:

  • To examine terms describing unresponsiveness where psychological factors are relevant.
  • To discuss the diagnostic criteria and place of functional coma among related disorders.
  • To identify reliable physical signs for diagnosing functional coma.

Main Methods:

  • Review of literature on functional coma and related conditions.
  • Analysis of physical signs associated with functional coma.
  • Discussion of diagnostic approaches, emphasizing positive findings over exclusion.

Main Results:

  • Firm resistance to eye opening and the eye gaze sign are identified as potentially sensitive and specific indicators.
  • Noxious stimuli, like Harvey's sign, may be helpful, but repeated painful stimuli are not recommended.
  • Physiological triggers, including general anesthesia, are also considered.

Conclusions:

  • Diagnosis of functional coma should rely on positive findings indicative of normal waking nervous system functioning despite apparent unresponsiveness.
  • Specific physical signs offer valuable diagnostic clues.
  • Distinguishing functional coma from other causes of unresponsiveness is crucial for appropriate management.