What does BEFAST (Balance, Eyes, Face, Arm, Speech, Time) mean in stroke evaluation?

BEFAST in Stroke Evaluation: A Comprehensive Screening Tool

BEFAST stands for Balance, Eyes, Face, Arm, Speech, and Time, which is an expanded stroke recognition tool designed to improve detection of stroke symptoms, particularly those associated with posterior circulation strokes.

Understanding BEFAST Components

BEFAST is an evolution of the widely used FAST (Face, Arms, Speech, Time) stroke recognition tool, with two additional components to enhance stroke detection:

1. Balance (B):

   • Assessment for sudden loss of balance, coordination problems, or difficulty walking
   • Helps identify cerebellar or brainstem strokes that may be missed by FAST alone

2. Eyes (E):

   • Evaluation for sudden vision changes, including double vision, blurred vision, or visual field defects
   • Targets posterior circulation strokes affecting visual pathways

3. Face (F):

   • Assessment for facial asymmetry or drooping
   • Patient is asked to smile or show teeth to reveal one-sided weakness

4. Arms (A):

   • Evaluation for arm weakness or drift
   • Both arms are extended forward with palms up to detect unilateral weakness

5. Speech (S):

   • Assessment for slurred speech, difficulty speaking, or inability to understand speech
   • Patient is asked to repeat a simple phrase

6. Time (T):

   • Emphasis on urgency - noting when symptoms began and calling emergency services immediately
   • Critical for time-sensitive interventions like thrombolysis

Clinical Significance and Evidence

The American Heart Association and American Red Cross guidelines recommend using stroke recognition scales such as FAST or Cincinnati Prehospital Stroke Scale to aid in recognizing acute stroke in adults 1. These tools are designed to be simple enough for first aid providers to use effectively.

The addition of Balance and Eyes components to create BEFAST was intended to improve detection of posterior circulation strokes, which may present with symptoms not captured by the original FAST acronym. Recent research shows that BE-FAST demonstrates higher sensitivity compared to FAST in identifying posterior circulation strokes (97.8% vs. 58.7%), though with lower specificity (10.0% vs. 39.8%) 2.

Implementation Considerations

Strengths of BEFAST

• More comprehensive coverage of stroke symptoms, particularly for posterior circulation events
• Potentially reduces missed stroke diagnoses
• Approximately 39.1% of patients with posterior circulation strokes might be missed if only FAST were used 2

Limitations of BEFAST

• Recent evidence suggests lower retention of all symptoms with BE-FAST compared to FAST (24.4% vs. 51.1% at 30 days) 3
• Adding Balance and Eyes components may actually reduce retention of the more common stroke symptoms like facial drooping and speech difficulties 3
• Some studies show comparable accuracy between BEFAST and FAST for stroke identification in prehospital settings (AUC = 0.70 vs. AUC = 0.69) 4

Current Adoption Patterns

There is variability in adoption of these mnemonics across healthcare institutions:

• Approximately 58% of Joint Commission-certified Comprehensive Stroke Centers use BEFAST in their educational materials
• 35% continue to use FAST
• 7% list no specific mnemonic 5

Practical Application

When using BEFAST to evaluate for possible stroke:

1. Assess Balance: Ask the person to stand and observe for instability or inability to maintain balance
2. Check Eyes: Ask about sudden vision changes and observe eye movements for abnormalities
3. Evaluate Face: Ask the person to smile and look for facial asymmetry
4. Test Arms: Have the person hold both arms out with palms up and eyes closed for 10 seconds to detect drift
5. Assess Speech: Ask the person to repeat a simple sentence and listen for slurring or inappropriate words
6. Time is Critical: Note when symptoms began and activate emergency services immediately

Recommendations for Practice

If stroke is suspected using any component of the BEFAST assessment, the emergency medical system should be activated immediately 1. Time is critical in stroke management, as treatment efficacy diminishes with delays.

For first aid providers, the use of a stroke recognition scale like BEFAST is recommended to aid in the recognition of acute stroke, though it's important to recognize that simpler tools like FAST may be more easily remembered by the general public 1.

While BEFAST offers improved sensitivity for detecting posterior circulation strokes, providers should be aware that this comes with potentially lower specificity and retention compared to the simpler FAST tool 2, 3.