The Injury Severity Score (ISS) is an established medical score to assess trauma severity.
It correlates with mortality, morbidity and hospitalization time after trauma. It is used to define the term major trauma. A major trauma (or polytrauma) is defined as the Injury Severity Score being greater than 15.
The AIS Committee of the
Association for the Advancement of Automotive Medicine (AAAM) designed and improves upon the scale.
Abbreviated Injury Scale (AIS)
The
Abbreviated Injury Scale (AIS) is an anatomically based consensus-derived global severity scoring system that classifies each injury in every body region according to its relative severity on a six-point
ordinal scale
Ordinal data is a categorical, statistical data type where the variables have natural, ordered categories and the distances between the categories are not known. These data exist on an ordinal scale, one of four levels of measurement described ...
:
# Minor
# Moderate
# Serious
# Severe
# Critical
# Maximal (currently untreatable).
There are nine AIS chapters corresponding to nine body regions:
# Head
# Face
# Neck
# Thorax
# Abdomen
# Spine
# Upper Extremity
# Lower Extremity
# External and other.
Definition
The ISS is based (see below) upon the
Abbreviated Injury Scale (AIS).
To calculate an ISS for an injured person, the body is divided into six ISS body regions. These body regions are:
*
Head
A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...
or
neck
The neck is the part of the body in many vertebrates that connects the head to the torso. It supports the weight of the head and protects the nerves that transmit sensory and motor information between the brain and the rest of the body. Addition ...
– including cervical spine
*
Face
The face is the front of the head that features the eyes, nose and mouth, and through which animals express many of their emotions. The face is crucial for human identity, and damage such as scarring or developmental deformities may affect th ...
– including the facial skeleton, nose, mouth, eyes and ears
*
Chest
The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen.
In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main di ...
– thoracic spine and
diaphragm
* Abdomen or pelvic contents – abdominal organs and lumbar spine
* Extremities or pelvic girdle –
pelvic
The pelvis (: pelves or pelvises) is the lower part of an anatomical trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis or pelvic skeleton).
...
skeleton
* External
To calculate an ISS, take the highest AIS severity code in each of the three most severely injured ISS body regions, square each AIS code and add the three squared numbers for an ISS ( where A, B, C are the AIS scores of the three most injured ISS
body
Body may refer to:
In science
* Physical body, an object in physics that represents a large amount, has mass or takes up space
* Body (biology), the physical material of an organism
* Body plan, the physical features shared by a group of anim ...
regions).
The ISS scores ranges from 1 to 75 (i.e. AIS scores of 5 for each category). If any of the three scores is a 6, the score is automatically set at 75. Since a score of 6 ("unsurvivable") indicates the futility of further medical care in preserving life, this may mean a cessation of further care in
triage
In medicine, triage (, ; ) is a process by which care providers such as Health professional, medical professionals and those with first aid knowledge determine the order of priority for providing treatment to injured individuals and/or inform th ...
for a patient with a score of 6 in any category.
[Trauma.org website. http://www.trauma.org/index.php/main/article/383/ Accessed Nov. 18, 2009]
References
External linksOnline Calculator of the Injury Severity Score
{{Trauma , state=autocollapse
Diagnostic emergency medicine
Diagnostic intensive care medicine
Medical scales