Assessment of probability of survival in penetrating injuries using the TRISS methodology.

By the TRISS methodology, probability of survival in injury can be estimated. It is based on a statistical analysis of outcome which is influenced by the severity of the injuries as expressed in the Injury Severity Score (ISS), the physiological function as expressed in the Trauma Score (TS) and the patient's age. We have used the TRISS formula in 206 patients with penetrating injury. Of these patients, 149 sustained stab wounds, 32 gunshot wounds and 25 others. ISS ranged from 2 to 38, the mean ISS being 9. The function was good (TS greater than 14) in 85 per cent. Estimated probability of survival ranged from 1.00 to 0.42. Three patients (1.5 per cent) died. The probability of their survival was 0.92, 0.96 and 0.98, respectively. All the fatal cases had serious predisposing conditions: chronic pulmonary disease, alcoholism, and psychiatric illness. In penetrating injury, the patient's functional status at the start of treatment is of greater importance for the outcome than the anatomical severity. The concept of the methodology of TRISS for assessment of probability of survival seems useful for review and comparison in injury care.