ISS - RTS - TRISS

(Injury Severity Score - Revised Trauma Score - Trauma Injury Severity Score)

Variables

Severity level (help)

Points

Head and neck

Face

Chest

Abdomen, pelvic contents

Extremity, pelvic girdle

External

ISS =
.

Respiratory rate (per min)

Systolic blood pressure (mmHg)

Glasgow coma scale (help)

RTS =
.

Age
(Pediatric cases (Ages < 15) use the blunt model for both blunt and penetrating mechanisms of injury.)

Predicted death rate (blunt)
TRISS =

Predicted death rate (penetrating)
TRISS =

ISS = Sum ((three most weighted region injury)²).
ISS equals 75 for any patient with an AIS 6 injury.

TRISS (blunt): Logit =-0.4499 + RTS*0.8085 + ISS*-0.0835 + (age.points)*-1.7430
Predicted death rate = 1/(1 + e^Logit)

TRISS (penetrating): Logit =-2.5355 + RTS*0.9934 + ISS*-0.0651 + (age.points)*-1.1360
Predicted death rate = 1/(1 + e^Logit)

RTS = Sum ((resp.rate.points)*0.2908; (sbp.points)*0.7326; (Glasgow.points)*0.9368)

References

Baker SP et al. The injury severity score: a method for describing patients with multiple injuries and evaluating emergency care. J Trauma 1974;14:187-96.
Champion HR et al. A Revision of the Trauma Score. J Trauma 1989;29:623-9.
Boyd CR et al. Evaluating Trauma Care : The TRISS Method. J Trauma 1987;27:370-8.
Champion HR et al. Coefficients update. J Trauma 1995 Editorial Comment. 38:94-5.

Web page by : Jean-Yves Marandon Centre Chirurgical Marie Lannelongue (France)

With help from Larry Bain, B.S.(Trianalytics.com),
Jean-Marc Rosengard (jmrosengard.com)
and Karim Brohi, BSc FRCS FRCA (Director, trauma.org)

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Definitions

The current definition of ISS as used in the TRISS model incorporates AIS 6 severity - described in the AIS Manual (AIS-90)

Recommendations For Uniform Reporting of Data following Major Trauma - The Utstein Style (An Initiative)
International Trauma Anaesthesia and Critical Care Society (ITACCS) Initiative
http://pdm.medicine.wisc.edu/itaccs.htm

Blunt injury : Non-penetrating, but including crush, laceration, amputation and asphyxia.
Penetrating injury : Bullet, knife, or spike.

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Eyes Open	Verbal	Motor
Spontaneous To speech To pain Absent	Converses / Oriented Converses / Disoriented Inappropriate Incomprehensible Absent	Obeys Localizes pain Withdraws (flexion) Decorticate (flexion) rigidity Decerebrate (extension) rigidity Absent

Variables	Severity level (help)	Points
Head and neck
Face
Chest
Abdomen, pelvic contents
Extremity, pelvic girdle
External
ISS = .
Respiratory rate (per min)
Systolic blood pressure (mmHg)
Glasgow coma scale (help)
RTS = .
Age (Pediatric cases (Ages < 15) use the blunt model for both blunt and penetrating mechanisms of injury.)
Predicted death rate (blunt) TRISS =		Predicted death rate (penetrating) TRISS =
ISS = Sum ((three most weighted region injury)²). ISS equals 75 for any patient with an AIS 6 injury.	TRISS (blunt): Logit =-0.4499 + RTS0.8085 + ISS-0.0835 + (age.points)*-1.7430 Predicted death rate = 1/(1 + e^Logit)	TRISS (penetrating): Logit =-2.5355 + RTS0.9934 + ISS-0.0651 + (age.points)*-1.1360 Predicted death rate = 1/(1 + e^Logit)
RTS = Sum ((resp.rate.points)0.2908; (sbp.points)0.7326; (Glasgow.points)*0.9368)