The Emergency Severity Index, ESI, v4

1. Emergency Severity Index, Version 4:
Implementation Handbook
Agency for Healthcare Research and Quality:
Pub. No. 05-0046-2, May 2005

2. “Triage” is derived from the French verb
“trier,” to “sort” or “choose.”
Originally the process was used by the
military to sort soldiers wounded in battle
for the purpose of establishing treatment
priorities.

3. Emergency Nurses Association (ENA)
Standards of Emergency Nursing Practice
The emergency nurse triages each patient and
determines the priority of care based on
physical, developmental and psychosocial needs
as well as factors influencing access to health care
and patient flow through the emergency care
system.
The goal is to rapidly gather “sufficient” information
to determine triage acuity. (ENA, 1999, p. 23).

4. It is recommended that comprehensive triage is to
be completed in 2 to 5 minutes, Travers (1999)
demonstrated at one tertiary center ED that this
goal was only met 22% of the time.
The triage nurse is expected to obtain a complete
history, take vital signs and complete department-
specific screening questions.

5. In 2003, the National Center for Health Statistics
found that 47% of EDs used 3-level triage
systems, while 20% used 4-level and 20% used 5-
level systems (personal communication, Catharine
Burt, Nov 1, 2004).
5-level triage 20%
4-level triage 20%
3-level triage 47%

6. Recent Trends Affecting ED
ED overcrowding
The American Hospital Association (2002)
reported 90% of hospital ED perceive they are at
or over operating capacity.
The average waiting time to be seen by an EP in
2001 was 49 minutes, which represented an
increase of 11 minutes from 1997 (McCaig &
Ly, 2002).

7. Triage Systems in the United States
Though many U.S. hospitals still use a 3- or 4-
level triage system, the trend is toward the use of
5-level systems.
Both ENA and the ACEP have come out in
support of 5-level triage systems for U.S. EDs.

8. Triage Systems in the United States
3 levels 4 levels 5 levels
• Emergent • Life-threatening • Resuscitation
• Urgent • Emergent • Emergent
• Nonurgent • Urgent • Urgent
• Nonurgent • Nonurgent
• Referred

9. Emergency Severity Index Conceptual Algorithm, v. 4
yes
patient dying? 1
no
yes
shouldn’t wait? 2
no
how many resources?
non one many
consider
5 4 vital signs
no
©ESI Triage Research Team, 2004. 3

10. 1
requires immediate life-saving yes
intervention?
no
high risk situation?
yes
or confused/lethargic/disoriented? 2
or severe pain/distress?
no
how many different resources are needed?
non one many
consider
danger zone vitals?
5 4 <3 m 3 m～3 y 3y～8y
HR >180 > 160 >100
RR >50 > 40 > 20
SaO2 <92%
©ESI Triage Research Team, 2004. no
3

11. Immediate Life-Saving Intervention
airway, emergency medications, hemodynamic
interventions (IV, O2, monitor, ECG or labs DO
NOT count); and/or any of the following clinical
conditions: intubated, apneic, pulseless, severe
respiratory distress, SpO2 <90, acute mental status
changes, or unresponsive.

12. High Risk Situation
Put patient in your last
open bed.
Severe pain/distress is
determined by clinical
observation and/or
patient rating of ≧ 7 on
0-10 pain scale.

13. Resources
 Count the number of different types of resources, not the
individual tests or X-rays (examples: CBC, electrolytes and
coags equals one resource; CBC plus CXR equals 2
resources).
Resources Not Resources
• Labs (blood, urine) • History & physical (including pelvic)
• ECG, X-rays • Point-of-care testing
• CT-MRI-ultrasound-angiography
• IV fluids (hydration) • Saline or heplock
• IV or IM or nebulized medications • PO medications
• Tetanus immunization
• Prescription refills
• Specialty consultation • Phone call to PCP
• Simple procedure =1 (lac repair, foley cath) • Simple wound care
• Complex procedure =2 (dressings, recheck)
(conscious sedation) • Crutches, splints, slings

14. Danger Zone Vital Signs
Consider up-triage to ESI 2 if any vital sign criterion
is exceeded.
Pediatric Fever Considerations:
 1 to 28 days of age: assign at least ESI 2 if temp >38.0 C
 1-3 months of age: consider assigning ESI 2 if temp
>38.0 C
 3 months to 3 yrs of age: consider assigning ESI 3 if
temp >39.0 C, or incomplete immunizations, or no
obvious source of fever