Aim of the lectureAim of the lecture

To understand the basic principles of injury

scoring systems.

To review the principal of anatomical and

physiological injury scoring systems.

So we should answer the following So we should answer the following questionsquestions

Why should severity be assessed

in trauma patients

How can severity be assessed in

trauma patients

Where pre-hospital or hospital

What is advantages and dis-

advantages

Trauma has been termed the neglected

disease of modern society, is among the leading

causes of death in all age groups. Each year it is

estimated that around 5.8 million people

worldwide die as a result of trauma, with 90%

of these deaths occurring in middle- and low-

income countries.

Trauma is the third cause of death after cancer and

cardiovascular diseases in the overall population.

Hemorrhagic shock and traumatic brain injury

(TBI) remain the leading causes of death accounting

respectively for 30% and 50% in trauma patients

arriving alive at the hospital (Harrois;etal 2013)

Severity assessment in trauma patients is

mandatory. when? It started during initial

phone call that alerts emergency services when

a trauma occurred. On-call physician assesses

severity based on witness provided information,

to adapt emergency response.

Whenever information comes, it helps providing

adequate therapeutics and orientating the patient

to the appropriate hospital. Severity assessment is

based upon pre-trauma medical conditions,

mechanism of injury, anatomical lesions and their

consequences on physiology.

Why should severity be assessed in trauma patients?Why should severity be assessed in trauma patients?System for field triageSystem for field triage

Assessment of injury severity is important clinically to

Correct triage of patients to a

trauma centre

Selecting the adequate intensity of care and to

prognosticating on short-/long-term patient outcome

It is also important to the comparison of trauma centres

Three main groups of trauma

scores

Anatomical ( measure static component of injury).

Physiological (measure acute dynamic component).

Combined

Anatomical Anatomical

Traumatic patients may have normal

physiology but may have anatomical

lesions that require high level of care

Injury Severity Score (ISS)

Abbreviated Injury Scale (AIS)

New Injury Severity Score (NISS)

Anatomic Profile (AP)

PhysiologicalPhysiological

(help determining prognosis)

Revised Trauma Score (RTS).

Glasgow Coma Score (GCS).

CombinedCombined

Trauma related Injury Severity Score -

(TRISS).

International Classification of Diseases

Diseases-based ISS - (ICISS).

Abbreviated Injury Scale - (AIS)Abbreviated Injury Scale - (AIS)One of the hospital scoresOne of the hospital scores

Was developed to rate and compare blunt injuries

from road vehicle accidents.

It has undergone several modifications since its

introduction in 1971. currently updating AIS -2000.

The AIS scores individual injuries and classifies them

into one of six categories, each with an associated

severity score ranges from1 (minor) to 6 (lethal).

The severity scores were subjectively assigned by experts.

Abbreviated Injury Scale - (AIS)

Injury - AIS score

1. Minor

2. Moderate

3. Serious

4. Severe

5. Critical

6. Un-survivable (fatal).

AIS – Limitations

No comprehensive measure of severity

Subjective

Not predicting patient outcomes or mortality

Injury Severity Score (ISS) Injury Severity Score (ISS)

Hospital score

The first significant scoring system to be based

primarily on anatomic criteria was developed in 1974.

Was created to define injury severity for comparative

purposes.

The strength of this system lies in its incorporation of

anatomic indices and severity indices.

Injury Severity Score

Six body regions

Head.

Face.

Chest.

Abdomen (including Pelvis).

Extremities.

External.

Example Injury Severity Score

Regioninjury descripitionAISSquare

top 3

Head&neck

Face

Chest

Abdomen

Extremity

External

ISS

Cerebral contusion

No injury

Flail chest

Liver contusion, spleen

Fracture femur

No injury

-------------------------------

3

0

4

5

3

0

9

0

16

25

50

Injury Severity Score… 3 most severely injured body regions – score

squared and added :

ISS = a2+b2+c2

Values ( 0 : 75 )

Patient with an ISS above 15 is considered as severe trauma patient.

Any lesion with an AIS of 6 will automatically lead to increase ISS severity score.

Limitations of Injury Severity

Score

Error in AIS scoring increases ISS error

Limits total number of injuries to 3 regions

Description of patient injuries unknown

Not a triage tool

Does not take into account age or co-morbidities

Not accurate for grading penetrating trauma

New Injury Severity Score -

NISS

Modified in 1997 from ISS

It equals “The sum of the squares of the AIS

of each of the three most severe AIS

injuries, regardless of the body region in

which they occur.

New Injury Severity Score

Predicts survival

Easier to calculate than ISS

Limitations of New Injury Severity

Score

No account for physiological variables

Anatomic Profile - (AP)

Because of ISS limitations,a multidimensional

characterization was sought that considers the

number, location and severity of anatomic injuries

and their influence on outcome. Includes all the

serious and non-serious a injuries.

Anatomic Profile

To describe apatient’s injuries: It uses Four categories (variables)

A - Head and spinal cord

B - Thorax and anterior neck

C - All remaining serious injuries

D - All non serious injuries.

Serious (AIS = ≥ 3)

Anatomic Profile The scores are combined using an Euclidean

Distance Model viz. the square root of the sum of the squares of the AIS scores of all serious injuries in each region.

No injury = Zero

allowing for decreasing influence of injuries as the number of injuries increases.

Limitations

Mathematical complexity

Trauma Score 1980 (TS) The widely used pre-hospital field triage tool ,it has

stood the test of time. a useful predictor of outcome for patients with blunt

or penetrating injuries.

Components Glasgow Coma Scale (GCS) Systolic Blood Pressure (SBP) Respiratory Rate (RR ) Respiratory expansion Capillary refill Revised due to difficult to

assess in the field(particularly at night)

Triage-Revised Trauma Score 1989

(RTS)

Components

Glasgow Coma Scale (GCS)

Systolic Blood Pressure (SBP)

Respiratory Rate (RR)

The Revised Trauma Score The Revised Trauma Score

Two types of RTS:

The coded form of the RTS is more frequently used

for quality assurance and outcome prediction. The

coded RTS is calculated as follows: RTSc = 0.7326

SBPc + 0.2908 RRc + 0 .9368 GCSc

Triage RTS: Determined by adding each of the

coded values together.

TheTriage- Revised Trauma

Score

Triage-Revised Trauma Score… Ranges 0:12 Score < 11 - transfer to trauma center (specificity 82%,

sensitivity59%) Predicting mortality with RTS:

RTS Mortality(%)

12 <110 126 372 700 >99

Champion HR, Sacco WJ, Copes WS, et al. A revision of the trauma score. J Trauma 1989;29:625, with permission

Limitations of Revised Trauma Score

Not practical in field

Underestimate the severity of head injury

Problems:

Intubated patients

Influence of alcohol

Drugs

The Glasgow Coma Scale - (GCS)

Best Eye Response. (4)

Best Verbal Response. (5)

Best Motor Response. (6)

1. No eye opening.

2. Eye opening to pain.

3. Eye opening to verbal command.

4. Eyes open spontaneously.

1. No verbal response

2. Incomprehensible sounds.

3. Inappropriate words.

4. Confused

5. Orientated

1. No motor response.

2. Extension to pain.

3. Flexion to pain.

4. Withdrawal from pain.

5. Localising pain.

6. Obeys Commands.

Trauma related injury severity score Trauma related injury severity score (TRISS) 1989(TRISS) 1989

Combination scoring system

Probability of trauma survival using anatomical and physiological scores.

A logarithmic regression equation is used:

Ps = 1/ (1+e^(-b)) , The b’s are regression coefficients.

where b = bo + b1(RTS) + b2(ISS) + b3(AgeScore).

RTS = (0.9368 x GCS) + (0.7326 x BPsys) +(0.2908 x RR)

ISS calculated as above

AgeScore = 0 if <55y or 1 if >55y.

Coefficients (b0 : b3) depend on type of trauma

TRISS – Limitations

Only moderately accurate for predicting survival

Problems already noted with the ISS

Similar to RTS, it can’t include tubed patients as

RR & verbal responses not obtainable

Multiple injuries to same body region cannot

measure

ASCOTASCOT)A Severity Characteristic of Trauma(

TRISS has been the pre-eminent trauma

outcome prediction model for the past 20 years. It

is used to compare patient outcomes. Its greatest

frailty is related to the Injury Severity Score (ISS).

For that reason, ISS was replaced in the TRISS

formulation by AP to create ASCOT.

When comparing ASCOT and TRISS, the

ASCOT performs much better on outcome

prediction than TRISS. However its “complexity”

has deterred many from implementing it and

TRISS still remains the mainstay of comparative

analysis of trauma patients. A study reporting the

replacement of ISS with NISS in TRISS would be a

worthwhile contribution.

In an attempt to create a score that

assesses severity in patients with medical

prehospital care, Sartorius et al. identified

four items that should be pooled:

NEW GAP

Risk categories in new GAP(Rebecca etal; 2010)

%GAP

(Total points)

MGAP

(Total points)

Low

Medium

High

<5%

5:50%

>50%

19 :24

11 :18

3 :10

23 : 29

18 : 22

3 : 17

Kondo et al. Critical Care 2011,

They studied 35,732 trauma patients in the Japan

Trauma Data Bank from 2004 to 2009 in multicenters, as

a prospective, observational study to assess whether the

new Glasgow Coma Scale, Age, and Systolic Blood

Pressure (GAP) scoring system, better predicts in-

hospital mortality and can be applied more easily than

previous trauma scores among trauma patients in the

emergency department (ED). they concluded that: The

GAP scoring system can predict in-hospital mortality

more accurately than the previously developed trauma

scoring systems.

ConclusionConclusion

All the above-mentioned scores have been developed

to predict mortality.

Severity assessment of trauma patient helps guiding

therapeutic, as well as orientating the patient in an

adequate hospital.

the GCS , RTS and GAP recommend these as the

most reliable prehospital triage instruments.

Instruments include ISS,NISS, TRISS and ASCOT

systems for assessing outcomes and mortality.

SummarySummary

Why should severity be assessed in trauma patients?

How can severity be assessed in trauma patients?

Where pre-hospital or hospital?

What is advantages and dis-advantages?

ReferencesReferences

http.//www.ATLS.org

http.//www.ITLS.org

http://www.jhsph.edu/Research/Centers/CIRP/ The Johns

Hopkins Center for Injury Research & Policy

http://www.trauma.org/A British web web-based trauma resource center

http://www.trauma.org/scores/rtscalc.html/Revised