(Kiosk 4) Limitations of Bedside Behavioral Evaluations in Detecting Covert Consciousness: A Case Report

Case Diagnosis: A 55-year-old man who presented as unresponsive was found to have covert consciousness.

Case Description or Program Description: A 55-year-old man who underwent emergent cervical spine fusion was found to be unresponsive following surgery. Imaging revealed multifocal infarcts involving the bilateral pons and thalami. Despite the family’s report of subtle interactivity and behavioral outflow, multiple providers consistently documented that the patient demonstrated eye opening without fixation or tracking and no command following, consistent with a diagnosis of a state of unresponsive wakefulness. Family was counseled regarding prognosis and was recommended to pursue long-term care options. The patient was evaluated by a physiatrist who identified contextually appropriate emotional responses and advocated for his acceptance into an acute rehabilitation Disorders of Consciousness (DoC) program.

Setting: Intensive care unit, Inpatient rehabilitation

Assessment/Results: On rehabilitation admission evaluation, the patient consistently followed eye-opening commands, fixated his gaze on the examiner, and tracked in the vertical plane. He demonstrated the characteristic bilateral horizontal gaze palsy of locked-in syndrome, which was felt to be the most appropriate diagnosis. He was started on fluoxetine and showed improvement in motor functioning, consistent command following, and sustained alertness. He developed consistent use of eyebrow raise for yes or no communication and progressed to a pureed diet with thin liquids.

Discussion (relevance): Covert consciousness describes patients who present as unresponsive or minimally responsive on standard bedside behavioral evaluations but display evidence of command-following on neuroimaging indicative of preserved consciousness. The estimated prevalence of covert consciousness among DoC patients is 15% but the distinction is often missed in the absence of neuroimaging studies.

Conclusions: Standardized bedside assessments are often inadequate to correctly identify patients with diagnoses that may result in covert consciousness. The failure to accurately detect covert consciousness can negatively impact the expected quality of life, discharge planning, and decisions regarding life-sustaining therapies in patients following severe brain injury.