Transcript Slide 1

Aim 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
questions
 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 disadvantages
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 lowincome 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?
System 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
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)
Physiological
(help determining prognosis)
 Revised Trauma Score (RTS).
 Glasgow Coma Score (GCS).
Combined
 Trauma related Injury Severity Score -
(TRISS).
 International Classification of Diseases
Diseases-based ISS - (ICISS).
Abbreviated Injury Scale - (AIS)
One 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)
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
AIS
Square
top 3
Head&neck Cerebral contusion
3
9
Face
No injury
0
0
Chest
Flail chest
4
16
Abdomen
Liver contusion, spleen
5
25
Extremity
Fracture femur
3
External
No injury
0
ISS
-------------------------------
Region
injury descripition
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
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
12
10
6
2
0
Mortality(%)
<1
12
37
70
>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. Incomprehensib
le 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
(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
ASCOT
(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
MGAP
(Total points)
(Total points)
<5%
19 :24
23 : 29
Medium
5:50%
11 :18
18 : 22
High
>50%
3 :10
3 : 17
%
Low
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 inhospital 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.
Conclusion
 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.
Summary
 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?
References

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