Evaluation of probability of survival using trauma and injury severity score method in severe neurotrauma patients

Abstract

Objective: Despite several limitations, the Trauma Injury Severity Score (TRISS) is normally used to evaluate trauma systems. The aim of this study was to evaluate the preventable trauma death rate using the TRISS method in severe trauma patients with traumatic brain injury using our emergency department data.

Methods: The use of the TRISS formula has been suggested to consider definitively preventable death (DP); the deaths occurred with a probability of survival (Ps) higher than 0.50 and possible preventable death (PP); the deaths occurred with a Ps between 0.50 and 0.25. Deaths in patients with a calculated Ps of less than 0.25 is considered as no-preventable death (NP). A retrospective case review of deaths attributed to mechanical trauma occurring between January 1, 2011 and December 31, 2011 was conducted.

Results: A total of 565 consecutive severe trauma patients with ISS>15 or Revised Trauma Score<7 were admitted in our institute. We excluded a total of 24 patients from our analysis : 22 patients younger than 15 years, and 2 patients with burned injury. Of these, 221 patients with head injury were analyzed in the final study. One hundred eighty-two patients were in DP, 13 in PP and 24 in NP. The calculated predicted mortality rates were 11.13%, 59.04%, and 90.09%. The actual mortality rates were 12.64%, 61.547%, and 91.67%, respectively.

Conclusion: Although it needs to make some improvements, the present study showed that TRISS performed well in predicting survival of traumatic brain injured patients. Also, TRISS is relatively exact and acceptable compared with actual data, as a simple and time-saving method.

Keywords: Survival; TRISS; Traumatic brain injury.

Fig. 1

A large amount of acute subdural hemorrhage along the right cerebral hemisphere; brain CT shows the mass effect with right subfalcine herniation (arrow).

Fig. 2

Acute diffuse subdural hemorrhage along the right cerebral hemisphere, brain CT shows severe brain swelling with effacement of CSF spaces, decreased gray-white matter demarcations (arrowhead), and midline shifting to the left (arrow, about 13 mm midline shift to left).