Trauma Scoring Flashcards
What is the AIS
Abbreviated injury scale
Anatomically based injury severity scoring system that classifies each injury by body region on a 6 point scale
It is used to determine the ISS
What are the 9 AIS regions
1) head
2) face
3) neck
4) thorax
5) abdomen/pelvic contents
6) spine
7) upper extremities
8) lower extremities
9) external
What is the maximum AIS score for any region and what does this mean?
6 - unsurvivable
What AIS score would you give for an injury of unknown severity?
2 - you have to code conservatively
From what source are the AIS scores based on? Ie where would the researcher look?
Patient records - so document clearly
If you score an AIS of 6 for any region what happens?
Your ISS automatically defaults to 75
What are the ISS regions?
Head, neck and c-spine Face Chest, thoracic spine, diaphragm Abdo/pelvic contents, lumbar spine Extremities and pelvic girdle External
How is the ISS calculated?
Take the top scoring AIS injury from the 3 top scoring regions
Square them
Add them together
Describe the revised trauma score and what it is based on
Physiological scoring system
GCS, SBP and RR
Which of the parameters in the RTS has the highest weighting and what does this mean
GCS > SBP > RR
That chance of survival is far more dependant on GCS than others
Does someone with a RTS of 0 or 8 have the highest chance of survival?
8
State the RTS coded values for GCS
4 = 13-15 3 = 9-12 2 = 6-8 1 = 4-5 0 = 3
Should you use GCS to describe a person who’s hit their head after 10 pints?
Nope, GCS is designed for purely head injured patients
What is the purpose of calculating PS
Allows comparative outcome analyses for hospitals to be performed
What variables were included in the TRISS model of PS
RTS, ISS, age and method of injury (blunt or penetrating)
What does the coefficient b mean in the PS
Dependant on if the injury is blunt or penetrating
What was wrong with the old TRISS model of PS?
Lots of unrecorded data for RR, SBP, and GCS
Patients transferred to another hospital for further care excluded
Patients intubated at scene were excluded
Children included in a way that isn’t statistically acceptable
What variables are included in the updated TARN PS model?
GCS (not RTS) ISS Age Gender Charlson index
What happens if, when calculating PS, GCS is missing?
Intubation status is used instead
What is the Charleston Index?
Adds a variable depending on patient comorbidities
What 2 coefficients have been added to the TARN PS model in 2014?
Patient comorbidities
True 30 day outcome (need to know post-discharge deaths)
What is the Ws Statistic?
Performance comparison graphs created for different hospitals to compare outcomes
What is the Ws Statistic based on?
AIS, ISS, W statistic, unexpected deaths, unexpected survivors
What are W, Z and M in the Ws Statistic?
W is actual survival rate - predicted survival rate
Z is the statistical significance of this survival rate
M coefficient is a measure of injury severity similarity
What are some flaws of trauma scoring systems?
Only the 3 highest scoring injuries influence the score
Excludes total injury load
Injuries may span multiple body regions
Doesn’t take into account mechanism of injury eg shooting over stabbing
Subjective
Relies on good documentation
Tiny mistakes in records make a big difference because of the squaring and multiplication
Give an example for each AIS severity
1: superficial laceration
2: fractured sternum
3: open humerus fracture
4: perforated trachea
5: ruptured liver with tissue loss
6: severed aorta
What components make up the ABC score?
penetrating injury mechanism
SBP <90 in ED
HR >120 in ED
+ve FAST
What does the ABC score indicate?
A score of 2 or more indicates the patient is likely to need a massive transfusion
