The Emergency Severity Index is a five level triage system. The five levels are discussed in my blog post The Emergency Severity Index: A Five Level Triage Tool Available For Download .
Level 1 patients, pediatric or adult, are clinically unstable and potentially require immediate life-saving treatment.
Examples of Level 1 pediatric patients are given in table 6-3, p 46:
Major head trauma with hypoventilation
Peticheal rash in a patient with altered mental status (regardless of vital signs)
• Decreased muscle tone
• Decreased mental status
• Bradycardia (late finding, concerning for impending cardiopulmonary arrest)
Shock/sepsis with signs of hypoperfusion
• Alteration in pulses: diminished or bounding
• Alteration in capillary refill time >3-4 seconds
• Alteration in skin appearance: cool/mottled or flushed appearance
• Widened pulse pressure
• Hypotension (often a late finding in the prepubescent patient)
Anaphylactic reaction (onset in minutes to hours)
• Respiratory compromise (dyspnea, wheeze, stridor, hypoxemia)
• Reduced systolic blood pressure
• Hypoperfusion (eg, syncope, incontinence, hypotonia)
• Skin and/or mucosal involvement (hives, itch-flush, swollen lips, tongue or uvula
• Persistent gastrointestinal symptoms.
*Gilboy N, Tanabe T, Travers D, Rosenau AM. Emergency Severity Index (ESI): A Triage
Tool for Emergency Department Care, Version 4. Implementation Handbook 2012 Edition.
AHRQ Publication No. 12-0014. Rockville, MD. Agency for Healthcare Research and Quality. November 2011. available at https://www.ahrq.gov/research/esi/esihandbk.pdf.