Neurological Assessment and Monitoring in the Critically Ill Child
Core concepts
Neurologic assessment of the critically ill child rests on serial, reproducible examinations rather than a single snapshot. Master the Pediatric Glasgow Coma Scale (eye, verbal, motor, age-adjusted for preverbal children), pupillary size and reactivity, brainstem reflexes (corneal, oculocephalic, gag), respiratory pattern, and motor asymmetry. Pair the exam with trended vital signs: Cushing triad (hypertension with widening pulse pressure, bradycardia, irregular respirations) signals raised intracranial pressure and is a late, ominous finding. Recall that infants may show a bulging fontanel, sunsetting eyes, or irritability alternating with lethargy instead of classic signs.
Monitoring modalities
Understand what each monitor measures and its limitations: intracranial pressure (ICP) waveforms and the meaning of P1/P2/P3, cerebral perfusion pressure (CPP = MAP − ICP), near-infrared spectroscopy (regional oxygen saturation), transcranial Doppler, pupillometry, and continuous EEG. Know that CPP targets are age-dependent and that a single normal ICP reading does not exclude intracranial hypertension.
Traps
Questions often test that sedation and paralysis blunt the exam, that the GCS verbal score in an intubated child is recorded as a tube (not a number) unless using a validated scale, and that a fixed dilated pupil may reflect herniation rather than medication. Do not confuse the Glasgow with the Full Outline of UnResponsiveness (FOUR) score.
Rule of thumb
When the exam and the monitor disagree, re-examine and treat the trend. A falling GCS of 2 points plus a new unequal pupil is a herniation emergency until proven otherwise.