Neurology · Year 3 · from Neurology

Case 3: Disorders of Consciousness

Patient Demographics

• Age: 45 years old
• Sex: Female
• Event: Cardiac arrest 6 weeks ago

Acute Event

Ms. Sarah Thompson suffered an out-of-hospital cardiac arrest 6 weeks ago secondary to ventricular fibrillation. CPR was initiated by bystanders after approximately 5 minutes of down time. ROSC (return of spontaneous circulation) was achieved after 18 minutes of resuscitation. She was treated with targeted temperature management (33°C for 24 hours) and remained comatose. She is now 6 weeks post-arrest, transferred to a specialized disorders of consciousness rehabilitation program for further assessment and treatment.

Current Examination

Level of Consciousness Assessment:

Arousal:

• Eyes open spontaneously
• Sleep-wake cycles present

Awareness:

• Does not follow commands
• No visual tracking
• Does not reach for objects
• No emotional responses to family members
• Occasional non-purposeful movements

Coma Recovery Scale - Revised (CRS-R):

CRS-R score <8 with no purposeful responses = Vegetative State/Unresponsive Wakefulness Syndrome

Clinical Image

Image: Diagram showing the spectrum of disorders of consciousness from coma (no wakefulness or awareness) through vegetative state (wakefulness without awareness) to minimally conscious state (inconsistent awareness) to emergence (functional communication or object use).

Image Source: Wikimedia Commons Attribution: Medical education, Public Domain URL: https://commons.wikimedia.org/wiki/File:Disorders_of_consciousness.png

Classification of Disorders of Consciousness

Diagnosis: Vegetative State (Unresponsive Wakefulness Syndrome) - 6 weeks post-anoxic injury

Diagnostic Workup

MRI Brain:

• Diffuse cortical and subcortical injury
• Particularly involving watershed zones
• Bilateral hippocampal atrophy

EEG:

• Severe diffuse slowing
• No reactivity to stimulation
• No seizure activity

Somatosensory Evoked Potentials (SSEP):

• Bilateral N20 responses present (favorable prognostic sign)

Family Meeting Discussion:

"Mrs. Thompson's brain was deprived of oxygen during her cardiac arrest, which caused widespread damage. She is currently in what we call a vegetative state - she has sleep-wake cycles and her eyes are open, but she is not showing awareness of herself or her environment.

At 6 weeks, it is still early. We consider a vegetative state 'persistent' after 1 month and 'permanent' after 3-12 months depending on the cause (longer timeline for traumatic injury, shorter for anoxic). The fact that her SSEP responses are present is a somewhat favorable sign.

We recommend a trial of specialized rehabilitation to see if she shows any signs of emerging awareness. We will monitor her closely and reassess her regularly. We also need to discuss her prior wishes and what she would want for herself in this situation."

Rehabilitation Approach

Goals of Rehabilitation in Disorders of Consciousness:

1. Optimize medical status
2. Provide sensory stimulation to promote recovery
3. Prevent complications (contractures, skin breakdown)
4. Serial assessment for signs of awareness
5. Support family coping and decision-making

Sensory Stimulation Program:

• Auditory: Familiar voices, music
• Visual: Faces, objects, light
• Tactile: Range of motion, textured objects
• Olfactory: Familiar scents (perfume, coffee)

Medical Management:

• Nutrition via PEG tube
• Bowel/bladder program
• DVT prophylaxis
• Contracture prevention (stretching, splinting)
• Spasticity management

Serial Assessment:

• CRS-R weekly
• Document any signs of purposeful behavior

Clinical Course

Week 8:

• No change in examination
• Family visiting daily, participating in stimulation program

Week 10:

• Nursing notes: "Patient appeared to track husband across room"
• CRS-R: Visual pursuit confirmed! (Score now 8)
• Diagnosis changed: Minimally Conscious State (MCS)

Week 12:

• Following simple commands inconsistently (squeeze hand)
• Emotional response to daughter's visit
• CRS-R: 14

Week 16:

• Following commands reliably
• Localizing to noxious stimuli
• Beginning to vocalize
• Diagnosis: Minimally Conscious State Plus (MCS+)

Family Meeting - Week 16

"Mrs. Thompson has shown significant improvement over the past 2 months. She has emerged from vegetative state and is now in what we call 'minimally conscious state plus' - she can follow commands and is showing signs of awareness, though still inconsistently.

This is meaningful progress and gives us reason for cautious optimism. However, I want to be honest that we still don't know how much further she will recover. Some patients with MCS continue to improve and regain functional communication; others remain at this level. We will continue rehabilitation and reassess."

Outcome at 6 Months Post-Arrest

• Following commands reliably
• Speaking single words
• Recognizing family members
• Feeding with assistance
• Severe memory impairment
• Requires 24-hour supervision and moderate assist for all ADLs

Discharge: To long-term care facility specializing in brain injury, with family involvement and continued outpatient therapies

Teaching Points

1. Disorders of consciousness exist on a spectrum:

• Coma → Vegetative State → Minimally Conscious State → Emergence

1. Vegetative state = wakefulness without awareness (eyes open, sleep-wake cycles, but no purposeful behavior)

1. Minimally conscious state shows inconsistent but reproducible signs of awareness (visual tracking, command-following, emotional responses)

1. CRS-R (Coma Recovery Scale-Revised) is the gold standard assessment tool for serial monitoring

1. Misdiagnosis of vegetative state is common (up to 40%) - careful serial assessment is essential

1. Prognostication is challenging:

• Anoxic injury: Generally poorer prognosis than traumatic
• Time matters: Earlier emergence = better outcome
• Negative SSEP: Very poor prognosis
• Positive SSEP: Does not guarantee good outcome but is favorable

1. Family support and honest communication are essential - help families understand prognosis while maintaining appropriate hope

Key Teaching Points Summary

Stroke Rehabilitation

• Neuroplasticity is activity-dependent; high-intensity therapy drives recovery
• FIM measures functional independence (1-7 scale per item)
• Interdisciplinary team: physiatrist, PT, OT, SLP, nursing, neuropsychology, social work
• Post-stroke depression is common (30-50%) and impairs rehabilitation
• Most recovery in first 3-6 months but continues with therapy

Spinal Cord Injury Rehabilitation

• ASIA classification (A-E) defines injury completeness
• Functional level (C6, T1, etc.) predicts independence potential
• Autonomic dysreflexia (T6 and above) is a medical emergency
• Neurogenic bladder/bowel require lifelong management
• Pressure ulcer prevention is critical

Disorders of Consciousness

• Spectrum: Coma → Vegetative → Minimally Conscious → Emerged
• Vegetative state = wakefulness without awareness
• CRS-R is gold standard for serial assessment
• Misdiagnosis is common - careful repeated assessment needed
• Family support and honest prognostic communication are essential

All cases for this lecture as Markdown