Pathophysiology
Clinical meaning
The PAT is a rapid 30-second across-the-room assessment evaluating three domains. Appearance (TICLS mnemonic: Tone, Interactiveness, Consolability, Look/gaze, Speech/cry) reflects adequacy of ventilation, oxygenation, and brain perfusion -- it is the most important component. Work of Breathing assesses respiratory effort through nasal flaring, retractions, head bobbing, tripod positioning, and audible sounds (stridor, wheezing, grunting). Circulation to Skin evaluates cardiovascular function via pallor, mottling, and cyanosis. The PAT generates six physiological categories: stable (all normal), respiratory distress (abnormal WOB only), respiratory failure (abnormal appearance + WOB), compensated shock (abnormal circulation only), decompensated shock (abnormal appearance + circulation), and cardiopulmonary failure (all three abnormal).