What is the motor response score on the Glasgow Coma Scale (GCS) for a patient who only opens their eyes?

Glasgow Coma Scale Motor Response Assessment

For a patient who only opens their eyes on the Glasgow Coma Scale (GCS), the motor response score is 1, indicating no motor response to stimuli.

Understanding the Glasgow Coma Scale Components

The Glasgow Coma Scale is a standardized clinical tool used to assess level of consciousness in patients with brain injury. It consists of three components:

1. Eye Opening (1-4 points)
2. Verbal Response (1-5 points)
3. Motor Response (1-6 points)

Motor Response Scoring (1-6 points)

The motor component of the GCS is scored as follows:

• 6: Obeys commands
• 5: Localizes to pain
• 4: Withdraws from pain
• 3: Abnormal flexion (decorticate posturing)
• 2: Extension (decerebrate posturing)
• 1: No motor response

When a patient only opens their eyes but shows no motor response to commands or painful stimuli, they receive the lowest motor score of 1 1.

Clinical Significance

A patient who only opens their eyes without demonstrating any motor response represents a severely impaired neurological state. This pattern indicates significant brain dysfunction, as the motor component is often the most resilient part of the GCS 2.

The motor component of the GCS has particular prognostic value:

• It has the strongest correlation with outcomes in traumatic brain injury
• It is less affected by confounders like intubation compared to the verbal component
• It provides critical information about brainstem function 1

Assessment Considerations

When evaluating a patient with this presentation:

• Ensure proper assessment technique by applying appropriate painful stimuli (central stimulus like trapezius squeeze or peripheral stimulus like nail bed pressure)
• Rule out confounding factors:
  • Sedation or neuromuscular blockade may artificially lower motor scores 2
  • Spinal cord injury can prevent motor response despite preserved consciousness
  • Drug or alcohol intoxication may affect responsiveness 1

Clinical Implications

A patient with eye opening only (motor score of 1) would have a maximum total GCS score of 5 (assuming a verbal score of 1 as well). This falls into the severe brain injury category (GCS ≤8) 1.

According to the National Expert Panel on Field Triage guidelines, patients with GCS <14 require transport to a trauma center, with those scoring GCS ≤8 needing immediate transfer to the highest level of trauma care available 2.

Common Pitfalls to Avoid

• Incomplete assessment: Always assess all three GCS components separately before calculating the total score
• Failure to perform serial assessments: The pattern of GCS changes over time has greater prognostic value than a single measurement 1
• Misinterpreting lack of response: Ensure that lack of motor response is not due to physical restraints, peripheral nerve injury, or spinal cord damage
• Overlooking brainstem reflexes: The FOUR score may provide complementary information about brainstem function in unresponsive patients 3

Remember that the GCS was originally developed for traumatic brain injury assessment, and its application to other causes of altered consciousness should be done with caution 4.