Feline Animal Trauma Triage Score: A Review of Published Literature

Philip R Judge BVSc MVS PG Cert Vet Stud MACVSc (Vet Emergency and Critical Care; Medicine of Dogs)

Introduction

The Animal Trauma Triage (ATT) score is the most widely used, system-based injury‐severity scale in small animal emergency medicine. Derived from six physiological domains, it provides a rapid, affordable bedside estimate of mortality risk. 

Since its original description in 1994, a growing feline-specific evidence base has emerged, to the point where a validated ATT score has been developed for cats. 

The six-category, 18-point ATT score remains the only general trauma severity index validated for feline patients. It is based on a rapidly acquired set of clinical observations, that is highly reproducible and linearly related to mortality. Every one-point rise almost doubles the odds of death¹. Its value is two-fold: guiding initial stabilisation decisions and stratifying risk in research.

This short review outlines findings in eight key studies that evaluated the ATT score in cats – including those derived from the large VetCOT (Veterinary Committee on Trauma) registry analyses, as well as focused investigations of common trauma syndromes – to help guide clinical application of the ATT score in cats, as well as directions for future research.

ATT Studies in Cats

Global validation of ATT in cats

A VetCOT registry study of 711 injured cats found the ATT showed excellent discrimination for in-hospital survival of patients. Each one-point increase in ATT raised the odds of death by 1.78, and a reduced three-category model (perfusion, neurologic, respiratory) retained near-identical performance¹. Additionally, the probability of death climbed steeply beyond a score of 6. 

When compared to the modified Glasgow Coma Score (mGCS), the ATT performed better than the mGCS in the same cohort, presumably due to its inclusiveness for whole-body injury assessment. 

Clinicopathological correlates in vehicular trauma

In a study of 75 cats involved in motor vehicle trauma, higher ATT (≥ 5) was strongly associated with several abnormalities, including anaemia, hypoproteinaemia, metabolic acidaemia, hyperlactataemia, hyperglycaemia and hypotension – clinical and laboratory parameters that likely reflect shock, haemorrhage, hypoperfusion and noradrenaline release – all direct consequences of trauma. Additionally, in this study, each one-point increment in ATT score raised the probability of the patient developing systemic inflammatory response syndrome by 15%. The findings in this study support that an elevated ATT score may correlate with clinically significant perfusion deficits and shock².

ATT in high-rise (fall) syndrome

A prospective Spanish study of 25 cats suffering from high-rise syndrome (falling from a height of 2 storeys or higher) demonstrated that ATT was the sole independent predictor of death after falls. An ATT of ≥ 6 yielded 75% sensitivity and 90% specificity for predicting death, while scores ≥10 were 100% predictive of mortality³. However, it was noted that thoracic injuries – common in high-rise syndrome in this patient cohort – did not translate to high ATT score values, highlighting a possible limitation of the score for detection of morbidity or possible n=mortality when these injuries are present.

Defining “severe trauma” in practice

The VetCOT registry was mined for cats with trauma to examine outcome. A report on data obtained from 3895 cats, to determine an ATT score that correlated with a description of “severe trauma”. The authors proposed an ATT score ≥ 3 as a practical definition of severe feline trauma. Cats with an ATT score above this cut-off had a three-fold lower survival to discharge (58.5% vs 96.6%) and required more surgery, transfusions and hospitalisation, validating the cut-point for triage and audit purposes⁴. Additionally, an ATT score >6 was associated with a mortality rate in excess of 50%, similar to findings in the study by Lapsey¹.

Interestingly, in this study, penetrating traumatic wounds carried the lowest median ATT score (1) and highest survival (90%), whereas combined blunt and penetrating trauma showed the highest proportion of severe scores (26%) and the worst outcome (68% survival to discharge)⁴.

Admission predictors and ATT thresholds

A large study of trauma in 530 cats explored readily measurable triage variables. The presence of hypothermia on admission, altered mentation (decreased level of consciousness component of the mGCS) and an ATT ≥ 5 independently predicted mortality on multivariable analysis. Results supported the use of the ATT threshold value of 5 to indicate “severe” injury⁵

Influence of trauma mechanism

Analysis of 3 895 VetCOT registry cases showed that trauma type modifies outcome despite similar ATT strata. Penetrating injuries carried the highest crude survival (90%), whereas mixed blunt-penetrating trauma had the worst survival rate (68%), reflecting differing pathophysiology and intervention profiles even at comparable ATT levels⁶.

Bite-wound trauma and ATT score

A reviews of 1065 cats with bite wounds found that for each unit rise in ATT score, odds of death increased 3.5-fold. Conversely, surgical intervention reduced the risk of death by 84% – regardless of ATT score. 

Increasing age increased mortality risk – with odds of non-survival increasing by 7% for every year of age. Increasing bodyweight reduced risk of death by 14% per kg of bodyweight. 

This study highlights the importance of full patient assessment of risk factors – not only in predicting outcome, but also in helping direct clinical decision-making⁷.  

Gunshot injuries

Although feline gunshot cases are rare, ATT still stratified survival likelihood. In a study of 8 cats and 29 dogs with gunshot injuries, an ATT score >4.5 predicted prolonged hospitalisation and death, supporting use of the scale in ballistic trauma where high velocity focal trauma can cause significant tissue injury distant from the site of projectile entry⁸.

Clinical implications

Score boundaries for characterisation of severe trauma:

Available evidence supports an ATT score ≥3–5 to indicate severe trauma, with a score of ≥6 highly specific for non-survival in high-rise falls. 

Score weighting influences clinical decision-making:
Perfusion and neurologic categories dominate prognostic weight; deficiencies here warrant immediate resuscitation.

Laboratory integration:
Shock-related biochemical derangements parallel ATT elevation; incorporating point-of-care lactate or base excess may refine risk stratification.

Mechanism matters:
Trauma aetiology influences survival independent of ATT, so reporting both score and mechanism improves prognostic accuracy and client communication.

The following table summarises the key clinical implications of the ATT score in cats, based on available evidence:

Future Study

Further research into the ATT score in cats may yield improvements in outcome prediction, including the following:

1. Prospective validation of abbreviated ATT models to streamline triage while retaining accuracy.
2. Dynamic scoring, assessing change in ATT over the first 6–12 hours as a marker of response to therapy, and how this affects prognosis.
3. Integration with advanced imaging and biomarker panels to create composite prognostic indices.
4. Outcome-driven cut-offs for specific mechanisms (e.g., vehicular vs penetrating trauma) to inform decision-making on surgery and referral.

Conclusions

Across diverse feline trauma scenarios, the ATT score remains a rapid, reliable predictor of mortality in cats suffering from a wide range of trauma. Its performance is consistent in large datasets and targeted syndromes, and is reliable when combined with simple clinical variables. Adoption of evidence-based boundaries for clinical decision-making and prognostication are valuable tools, and enhance its clinical utility in feline emergency care.

References

1. Lapsley J, Hayes GM, Sumner JP. Performance evaluation and validation of the Animal Trauma Triage score and modified Glasgow Coma Scale in injured cats: a Veterinary Committee on Trauma registry study. J Vet Emerg Crit Care. 2019;29(5):478-483.
2. Lyons BM, Ateca LB, Otto CM. Clinicopathological abnormalities associated with increased animal triage trauma score in cats presenting for vehicular trauma: 75 cases (1998–2009). J Vet Emerg Crit Care. 2020; 30:693-697.
3. Girol-Piner AM, Moreno-Torres M, Herrería-Bustillo VJ. Prospective evaluation of the Animal Trauma Triage Score and Modified Glasgow Coma Scale in 25 cats with high-rise syndrome. J Feline Med Surg. 2022;24(6): e13-e18.
4. Lee JA, Huang CM, Hall KE. Epidemiology of severe trauma in cats: an ACVECC VetCOT registry study. J Vet Emerg Crit Care. 2022; 32:705-713.
5. Fitzgerald RF, et al. Clinical parameters at time of admission as prognostic indicators in cats presented for trauma. J Feline Med Surg. 2022; 24:1293-1304.
6. Gregory CW, Davros AM, Cockrell DM, Hall KE. Evaluation of outcome associated with feline trauma: a Veterinary Committee on Trauma registry study. J Vet Emerg Crit Care. 2023; 33:201-207.
7. Tinsley AT, Oyama MA, Reineke EL. Animal Trauma Triage Score, Modified Glasgow Coma Scale, age and weight were associated with outcome in feline bite wounds (1 065 cases). J Am Vet Med Assoc. 2023;261(6):881-889.
8. Olsen LE, Streeter EM, DeCook RR. Review of gunshot injuries in cats and dogs and utility of a triage scoring system to predict short-term outcome: 37 cases (2003–2008). J Am Vet Med Assoc. 2014;245(8):923-929.

The Animal Trauma Triage (ATT) score for Cats