Page 12 - 62 paediatric-trama25-29_opt

168 Paediatric Injury Scoring and Trauma Registry
Trauma and ISS Table 26.8: CRAMS scale.
The TRISS is a combination of the physiologic data in the RTS (and, Clinical
less commonly, the TS) and anatomic data in the ISS to estimate the parameter Parameter category Coded value
2,3
probability of survival for a given trauma patient. The probability Normal capillary refill, SBP >100 mm Hg 2
of survival [P(s)] for any one patient is determined by the formula. 1,2,3
Delayed capillary refill, SBP 85–100
Circulation 1
–b
P(s) = 1/(1 + e ), mm Hg
No capillary refill or SBP <85 mm Hg 0
where b = b + b (TS or RTS) + b (ISS) + b (age factor). The b coef-
0 1 2 3
ficients (b , b , b , and b ) are derived from logistic regression analysis
0 1 2 3 Normal 2
of patients in the Major Trauma Outcome Study (MTOS) data base.
These coefficients are different for blunt and penetrating trauma. The Respiration Abnormal (laboured or shallow) 1
age factor (or age index, as used by other authors) is zero for all patients
aged <55 years and 1 for all patients aged ≥55 years. If the patient is Absent 0
1
younger than 15 years of age, the blunt index for b is used regardless of Abdomen and thorax nontender 2
3
mechanism. Values for P(s) range from 0, for no survival expectation,
to 1.00 for 100% survival expectation. Generally, survivors have a P(s) Abdomen/thorax Abdomen and thorax tender 1
1
≥ 0.5, and nonsurvivors have a P(s) < 0.5. Trauma fatalities with a P(s) Abdomen and thorax rigid, flail chest, or
< 0.5, by convention, are defined as expected outcomes, and fatalities penetrating trauma 0
with a P(s) ≥ 0.5 are unexpected outcomes. This terminology is impor- Normal 2
tant for quality evaluation of trauma care. There is also the Paediatric
Age-Adjusted TRISS, which simply uses the paediatric Age Specific Motor Responds only to pain (other than 1
decerebrate)
3
PTS instead of the RTS, but this is not yet in wide use by investigators.
The drawbacks of the TRISS are primarily related to the component No response (or decerebrate) 0
scoring systems that form its basis: the RTS (or TS or PTS) and the Normal 2
ISS. It is also not easy to compute due to a complex logistic regression
2
formula used to calculate P(s). Despite all these limitations, TRISS Speech Confused 1
is the most validated and commonly used trauma mortality prediction
model to date, and its methodology has been shown to perform No intelligible words 0
reasonably well for both adult and paediatric trauma patients. 1
ASCOT Table 26.9: Paediatric Trauma Score.
The developers of ASCOT designed it as a mortality prediction model
to improve on the limitations of the TRISS. ASCOT uses the AP Clinical parameter Severity category Score value
1
instead of the ISS for the description of an anatomic injury. It also uses Weight ≥ 20 kg +2
separate algorithms for blunt and penetrating trauma. ASCOT takes into
account each injury within a given body region by using the AP and, 10–19 kg +1
as such, better represents the increased mortality risk associated with <10 kg -1
multiple injuries. The AP, as used in ASCOT, divides serious injuries
1
(AIS > 2) into three categories—head, brain or spinal cord injuries; tho- Airway Normal +2
rax or neck injuries; and all other serious injuries. Note that nonserious Maintainable +1
injuries (AIS of 1 or 2) are not significantly associated with mortality
and are therefore dropped from ASCOT calculations. Unmaintainable -1
Like the TRISS, ASCOT relies on the RTS to provide physiologic Systolic blood pressure* >90 mm Hg +2
data but advocates the use of the individual components of the RTS
rather than the total RTS score. It derives a measure of the probability 50–90 mm Hg +1
of survival by combining values of the GCS, SBP, and RR as coded <50 mm Hg -1
by the RTS, patient age (0 for all paediatric patients) and the AP. P(s)
3
using ASCOT is calculated similarly to the TRISS by employing the Central nervous system Awake +2
following formula: 1,2
Obtunded/loss of consciousness +1
P(s) = 1/(1 +e ),
–k
Coma/decerebrate -1
where k = k + k (RTS GCS value) + k (RTS SBP value) + k (RTS RR
1 2 3 4 Open wound
value) + k (AP head region value) + k (AP thorax region value) + k (AP None +2
5 6 7
other serious injury value) + k (age factor).
8 Minor +1
The k coefficients for blunt and penetrating injuries are all
derived from the MTOS data base and can be found in the literature. Major or penetrating -1
ASCOT is more cumbersome to compute than the TRISS but appears Skeletal injury
to be more accurate at predicting trauma mortality, especially for None +2
1
penetrating injuries. Closed fracture +1
Table 26.10 demonstrates example calculations of some of the
trauma scores by using a single hypothetical case scenario: A 13-year- Open or multiple fractures -1
old boy, weighing 35 kilograms, was standing by the side of the road
and was struck by a moving vehicle, hitting his head against the edge of *In the absence of a proper-sized blood pressure cuff, BP can be assessed by
assigning the following values: presence of palpable pulse at the wrist = +2;
3
a gutter. On arrival at the Accident and Emergency (A&E) department presence of a palpable pulse at the groin = +1; absence of pulse = –1.