A 32-year-old man with severe TBI (GCS 5T) has a ventriculostomy catheter in place. The nurse reviews the ICP waveform and identifies a repeating pattern: three ascending waves per cardiac cycle -- P1 (percussion wave), P2 (tidal wave), P3 (dicrotic wave). The current ICP is 18 mmHg. The nurse notices that the P2 wave amplitude is higher than the P1 wave amplitude (P2 > P1). What does this waveform finding indicate?
