What scales are used to assess ischemic stroke in intubated patients in the Intensive Care Unit (ICU)?

Assessment Scales for Ischemic Stroke in Intubated ICU Patients

The National Institutes of Health Stroke Scale (NIHSS) with modifications for intubated patients is the primary recommended scale for assessing ischemic stroke in intubated ICU patients, supplemented by the Full Outline of UnResponsiveness (FOUR) score which provides better assessment of brainstem function and respiratory patterns in intubated patients.

Primary Assessment Scales

1. Modified NIHSS for Intubated Patients

The NIHSS is the most widely used and validated stroke assessment tool that quantifies stroke severity on a scale from 0 to 42, with higher scores indicating more severe strokes 1. For intubated patients:

• Most components of the NIHSS can still be assessed in intubated patients
• For item #10 (dysarthria), mark "X" to indicate intubation/mechanical barrier 1
• For item #9 (language), assessment can still be performed through written communication or other non-verbal responses
• The scale should be administered at regular intervals as part of neurological monitoring in the ICU 1

2. FOUR (Full Outline of UnResponsiveness) Score

The FOUR score addresses specific limitations of the GCS in intubated patients and provides complementary information to the NIHSS 2, 3:

• Consists of four components (eye, motor, brainstem, and respiration), each scored 0-4
• Does not rely on verbal response, making it ideal for intubated patients
• Assesses brainstem reflexes and breathing patterns not captured by NIHSS
• Superior in detecting subtle changes in neurological status in comatose patients
• Can identify locked-in syndrome and different stages of herniation 2
• Has excellent inter-rater reliability (kappa = 0.82) 2
• Better predictor of early mortality in intubated patients compared to GCS 3

Monitoring Protocol for Intubated Stroke Patients in ICU

Frequency of Assessment

• For thrombolysis-treated patients: Every 15 minutes for first 2 hours, then every 30 minutes for 6 hours, then hourly for 16 hours 1
• For non-thrombolysis patients: Hourly with neurological checks or more frequently if necessary 1
• Temperature monitoring every 4 hours for the first 48 hours 1

Additional Assessment Components

1. Vital Signs Monitoring:

   • Blood pressure (call physician if systolic BP >220 or <110 mm Hg; diastolic BP >120 or <60 mm Hg) 1
   • Heart rate and rhythm (continuous cardiac monitoring for 24-72 hours) 1
   • Respiratory rate and oxygen saturation (maintain O₂ saturation >92%) 1

2. Positioning Assessment:

   • Head of bed position (individualized based on risk of increased ICP and aspiration) 1
   • Optimal positioning to prevent aspiration in patients with hemiparesis 1

3. Functional Assessment:

   • Barthel Index can be used to track functional recovery once the patient is extubated 1
   • Measures activities of daily living on a scale of 0-100

Special Considerations for Intubated Patients

1. Advantages of FOUR score over GCS in intubated patients:

   • 81.4% of ICU nurses preferred FOUR score over GCS (0%) for intubated patients 4
   • FOUR score identified 11% of patients classified as vegetative state by GCS as actually being in minimally conscious state 5
   • FOUR score demonstrated better prediction of early mortality in intubated patients with AUC of 0.90 compared to GCS's AUC of 0.80 3

2. Respiratory component assessment:

   • FOUR score includes assessment of respiratory drive and ventilator dependency 2
   • Can detect breathing pattern abnormalities that may indicate brainstem dysfunction

3. Communication strategies:

   • Use visual cues, written communication, or simple commands with yes/no responses
   • Assess eye movements and motor responses carefully as primary communication methods

Implementation in Clinical Practice

• All ICU staff should be trained in both NIHSS and FOUR score assessment 1
• Standardized protocols should be used to ensure consistent assessment 1
• Regular neurological assessments should be documented to track changes over time
• Rapid response protocols should be in place for neurological deterioration

Pitfalls to Avoid

1. Do not rely solely on GCS for intubated stroke patients as it cannot fully assess verbal components and lacks brainstem assessment 2, 3

2. Do not assume lack of response equals lack of consciousness - FOUR score can detect subtle signs of consciousness not captured by other scales 5

3. Do not delay assessment - in-hospital stroke assessment is often delayed compared to ED assessment (4.5 hours vs 1.2 hours to neuroimaging) 1

4. Do not overlook brainstem function - assessment of pupillary light reflexes, corneal reflexes, and respiratory patterns provides critical information about brainstem integrity 2

The combination of modified NIHSS and FOUR score provides the most comprehensive assessment of neurological status in intubated ischemic stroke patients in the ICU setting, allowing for better monitoring of clinical progression and prediction of outcomes.