Although the Abbreviated Injury Scale (AIS) has been a widely utilized and generally powerful injury scaling system for trauma researchers, it has had serious deficiencies in the area of head injury. The AIS 1980 revision (AIS-80) has been substantially modified for the coding of brain iniury. This was done in order to minimize ambiguities previously present and to reflect the complex interaction of both pathological and physiological disturbances which result from brain injury.
This report provides the first utilization of the AIS-80 in head injured patients. AIS scores were given to 434 patients admitted to the University of Pennsylvania Head Injury Center. The AIS value was then correlated with outcome according to the five point Glasgow Outcome Scale. Results of these analyses showed a chi square significant correlation of the AIS score to outcome of p < 0.0001. Low AIS scores were associated with uniformly good recovery whereas the percentage of good recovery decreased progressively as the AIS severity score increased. At AIS 5 (the highest injury severity) only 10% has a good recovery. Similarly no deaths occurred in AIS 1 and 2. Only 3% of patients with AIS scores 3 and 4 died whereas 38% with AIS 5 died. All patients who survived in a vegetative state had AIS 5 scores.
These highly significant correlations suggest that the AIS-80 system successfully achieves its intended purpose of ranking brain injury severity. The AIS-80 modifications, and correlations to other injury severity measures are presented.