How do you assess the Glasgow Coma Scale (GCS) in an infant?

Assessing Glasgow Coma Scale in Infants

Use a modified pediatric Glasgow Coma Scale (pGCS) that adapts the verbal and motor components to age-appropriate developmental milestones, recognizing that infants under 2 years cannot provide the verbal responses required by the standard adult GCS. 1

Key Modifications for Infant Assessment

The pediatric GCS was specifically developed in 1988 for children 5 years of age or younger who cannot provide necessary verbal responses to score the standard GCS. 1 However, the pGCS has significant limitations and has not achieved universal adoption in clinical practice. 1

Modified Verbal Component for Infants

For infants under 2 years, the verbal score is adapted to assess:

• V5: Coos, babbles appropriately, smiles socially 2
• V4: Cries but is consolable 2
• V3: Persistently irritable, inconsolable crying 2
• V2: Restless, agitated, moaning 2
• V1: No verbal response 2

Modified Motor Component for Infants

The motor assessment adapts to infant capabilities:

• M6: Moves spontaneously and purposefully 2
• M5: Withdraws to touch 2
• M4: Withdraws to pain 2
• M3: Abnormal flexion (decorticate posturing) 2
• M2: Abnormal extension (decerebrate posturing) 2
• M1: No motor response 2

Eye Opening Component

The eye opening component remains unchanged from the adult scale and can be reliably assessed in infants. 3

Critical Assessment Principles

Always document individual E, V, and M scores separately (e.g., E3V4M5 = 12) rather than just the sum, as infants with identical total scores but different component profiles have vastly different outcomes and prognoses. 4

Assess pupils simultaneously with GCS, as pupillary size and reactivity are key prognostic indicators that maintain value regardless of age. 4

Perform serial assessments rather than single determinations, as declining scores indicate poorer prognosis and provide substantially more valuable clinical information. 4, 5

Important Limitations and Pitfalls

The reliability of the pGCS has been questioned because the scoring system is based on patients' understanding of orders and commands, which may not be applicable to very young children. 1 The pGCS requires refined clinical skills to be properly applied. 1

For severe TBI in children, some authors propose decreasing the cut-off to GCS ≤5 rather than ≤8 due to distinct pathophysiology of TBI in children. 1

Alternative Approach: AVPU Scale

In resource-limited settings or when basic emergency medical technicians are performing the assessment, the AVPU scale (Alert, Verbal, Pain, Unresponsive) is often preferred as it is conceptually simpler and has gained popularity especially in low and middle-income countries. 1

Novel Infant-Specific Scales

The CHOP Infant Coma Scale (Infant Face Scale) demonstrated superior interrater reliability compared to GCS in children under 2 years, particularly for the verbal/face component, and can be applied to intubated patients. 3 However, this scale has not achieved widespread clinical adoption.

A grimace score has been developed for intubated infants and shows better reliability than the verbal score when the verbal component cannot be assessed. 6

Clinical Application in Trauma

For infants under 2 years with head trauma, the PECARN criteria use GCS = 15 or GCS = 14 as key decision points, with GCS = 14 or other signs of altered mental status placing the infant in the high-risk category requiring imaging. 1

Any infant with GCS <14 warrants the highest level of trauma activation and immediate transport to a trauma center. 1, 7