What 3 things are in the Paediatric Assessment Triangle (PAT) and why would you need to perform it?

For ill children 1- Appearance: Muscle tone, consolability, spontaneous movements, speech or cry, distress level 2- Work of Breathing: effort, Respiratory distress, abnormal airway sounds 3- Circulation to skin: Skin color, such as pale, mottled, cyanotic, or flushed, bleeding, sweating