Philips V24CT User's Reference Manual page 280

Viewing Neonatal Events
The severity of an event is indicated by the length of the event bar; the
longer the event bar, the more severe the event.
The Bradycardia and Desaturation event bars start at the top of their
channels and extend downwards. The Apnea event bars start at the
bottom of the Apnea channel and extends upwards.
The Manual Event Bar is only a marker to be selected by the graph
cursor.
9-6 Neonatal Event Review
(1) Associated Event
(2) Isolated Event
(3)Cursor