Injury Severity Score (ISS)
Standardizes severity of trauma.
id
1239
full_title
Injury Severity Score (ISS)
short_title
Injury Severity Score (ISS)
med_description
Standardizes severity of traumatic injury based on worst injury of 6 body systems.
description
The Injury Severity Score (ISS) Standardizes severity of traumatic injury based on worst injury of 6 body systems.
keywords
Injury Severity Score (ISS), ISS, ISS calc, ISS online, ISS mdcalc, ISS score, ISS prognosis, injury severity, injury severity calc, injury severity score, injury severity mdcalc, injury severity online, injury severity trauma, injury prognosis, injury unsurvivable, injury unsurvivable calc, injury prognosis
complaint
[ "Injury/Trauma" ]
formula
Assign an Abbreviated Injury Scale (AIS) Score to the most severe injury in each body system as follows: Then, if the 3 most severe injuries in 3 body systems are A, B, and C, then ISS = A² + B² + C² If a patient has an AIS of 6 in any body system, they are automatically assigned an ISS of 75.
evidence
-
The ISS was derived by Baker et al (1974) by taking the previously used Abbreviated Injury Scale (AMA Committee on Medical Aspects of Automotive Safety 1971) and adding up the squares of each of the three most severe body systems, in an effort to add increasing weight to the most severe injuries.
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The top three most severe injuries were used to calculate the final score because it was shown that injuries that alone would not necessarily be life threatening, had a significant effect on mortality when occurring in combination with other severe injuries.
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The derivation study included only injuries sustained from motor vehicle collisions, including occupants of the vehicles as well as pedestrians involved.
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Further validation studies have validated the study to include other mechanisms of injury.
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A study of 875 patients with gunshot wounds by Beverland et al (1983) showed that an increasing ISS was associated with increasing mortality (chi-squared = 83.31, p <O.0Ol).
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A study by Bull (1978) confirmed the correlation between increasing ISS and increasing mortality for road traffic accidents, as well as increasing mean hospital length of stay with increasing ISS.
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Semmlow and Cone (1976) found similar findings to Baker et al in terms of relationship between ISS and mortality when they looked at 8,852 trauma patients from the Illinois Trauma Program, including both vehicular and non-vehicular trauma. They also found ISS to correlate with hospital length of stay.
measurements
[]
information
refrences
{ "Clinical Practice Guidelines": [], "Manufacturer Website": [], "Original/Primary Reference": [ { "href": "https://www.ncbi.nlm.nih.gov/pubmed/4814394", "text": "Baker SP, O'Neill B, Haddon W Jr, Long WB. The injury severity score: a method for describing patients with multiple injuries and evaluating emergency care. J Trauma. 1974 Mar;14(3):187-96. PubMed PMID: 4814394." } ], "Other References": [ { "href": "https://www.ncbi.nlm.nih.gov/pubmed/5107365", "text": "Rating the severity of tissue damage. I. The abbreviated scale. JAMA. 1971;215(2):277-80." }, { "href": "https://www.ncbi.nlm.nih.gov/pubmed/965234", "text": "Semmlow JL, Cone R. Utility of the injury severity score: a confirmation. Health Serv Res. 1976;11(1):45-52." }, { "href": "https://www.sciencedirect.com/science/article/pii/0020138378900049", "text": "Bull JP. Measures of severity of injury. Injury. 1978;9(3):184-7." }, { "href": "https://www.ncbi.nlm.nih.gov/pubmed/3123707", "text": "Copes WS, Champion HR, Sacco WJ, Lawnick MM, Keast SL, Bain LW. The Injury Severity Score revisited. J Trauma. 1988;28(1):69-77." } ], "Outcomes": [], "Validation": [ { "href": "https://www.ncbi.nlm.nih.gov/pubmed/6885141", "text": "Beverland DE, Rutherford WH. An assessment of the validity of the injury severity score when applied to gunshot wounds. Injury. 1983;15(1):19-22." } ], "Validations": [] }
pearls
-
Initially derived in patients with blunt traumatic injury from motor vehicle accidents only.
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The ISS is not intended to be used for bedside decisions regarding a single patient in the emergency department setting, but rather as a tool to standardize the study of trauma patients.
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Due to the nature of the score, multiple combinations of Abbreviated Injury Scale (AIS) scores may arrive at the same ISS, each of which may indicate a different mortality rate. For example, an ISS of 17 can be made from patients with a combination of points based on the three most severe injuries, such as (4, 1, 0) or (3, 2, 2). The ISS also gives equal importance to each body region.
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Patients with an AIS of 6 in any body system are automatically assigned an ISS of 75, the maximum possible score.
usecase
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The ISS is a score that attempts to standardize the severity of injuries sustained during a trauma.
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This standardization allows one to more accurately study and predict morbidity and mortality outcomes after traumatic injuries.
reasons
Due to the heterogeneous nature of trauma patients, standardizing severity of traumatic injury allows for much larger sample populations in trauma research studies.
next_advice
As the ISS is intended as more of a research tool, calculation of the ISS should not affect initial management of the patient with traumatic injuries.
next_actions
next_management
- In all trauma patients, initial treatment strategy should focus on the primary and secondary survey, and assessing and stabilizing the patient.
- This score is intended mostly for research purposes but may have broader clinical use in the ICU for prognostication following initial stabilization of traumatic injuries.
diseases
[ "Trauma" ]
instructions
Rate only the most severe injury from each body system. Used primarily in research settings, so calculation of the ISS should not delay initial management of patients with traumatic injuries.
published
2022-04-21T20:28:57.678Z
purpose
[ "Formula", "Prognosis" ]
search_terms
[ "trauma" ]
seo
{ "keywords_en": "Injury Severity Score (ISS), ISS, ISS calc, ISS online, ISS mdcalc, ISS score, ISS prognosis, injury severity, injury severity calc, injury severity score, injury severity mdcalc, injury severity online, injury severity trauma, injury prognosis, injury unsurvivable, injury unsurvivable calc, injury prognosis", "meta_description_en": "The Injury Severity Score (ISS) Standardizes severity of traumatic injury based on worst injury of 6 body systems." }
specialty
[ "Critical Care", "Emergency Medicine", "Surgery (General)", "Surgery (Trauma)" ]
departments
[ "Any/All" ]
tags
[]
version_number
1
versions
[]
related
[ { "calcId": 10185, "short_title_en": "Pediatric Trauma Score (PTS)", "slug": "pediatric-trauma-score-pts" }, { "calcId": 4028, "short_title_en": "BLI Severity Score", "slug": "blast-lung-injury-severity-score" }, { "calcId": 4030, "short_title_en": "Bastion Classification", "slug": "bastion-classification-lower-limb-blast-injuries" } ]
ismed
true
section
[ "whenToUseViewed", "pearlsPitfallsViewed", "whyUseViewed", "nextStepsViewed", "evidenceViewed" ]
cleaned_departments
[ "any" ]
cleaned_use
[ "The ISS is a score that attempts to standardize the severity of injuries sustained during a trauma.", "This standardization allows one to more accurately study and predict morbidity and mortality outcomes after traumatic injuries." ]
pub
true