Figure 1.

Multimodal monitoring during plateau waves in intracranial pressure (ICP) after traumatic brain injury (TBI). This is a pediatric patient who sustained severe TBI with moderate diffuse axonal injury (Marshall grade 3) on initial computed tomography scan. During the monitoring on the pediatric intensive care unit the patient developed rapid and short-lived increases in ICP (blue) in a pattern known as intracranial plateau waves. This corresponds with a reduction in cerebral perfusion pressure (CPP, gold) and a deranged cerebrovascular autoregulation (PRx, green). PRx—pressure reactivity index—is a measure of the capacity of the cerebral vasculature to alter its resistance in response to changes in CPP. A negative PRx indicates intact pressure reactivity whereas a positive PRx indicates impaired pressure reactivity.