Factors affecting outcome in the pediatric patient with multiple trauma. Further experience with the modified injury severity scale.

In a 5-year period of prospective study, 369 pediatric patients with multiple trauma (injury to at least two body areas) had injuries scored by a Modification of Injury Severity Scale (MISS). This scale uses the categories and rankings of the Abbreviated Injury Scale-1980 (AIS-80) except that the classification of neurological injuries are scored by the Glasgow Coma Scale (GCS) and other neurological findings (presence of a surgical mass lesion, pupillary light response, and oculocephalic reflexes). The MISS is calculated as the sum of the squares of the three most severely injured body areas. The mean MISS score was 23.8 with 33% of MISS scores greater than 25 and 67% less than 25. Among those with MISS scores greater than 25 there was a 44% mortality and 31% disability. In the group with MISS scores less than 25, there were no mortalities, and a 1% disability (p less than 0.001). Overall mortality was 14% with 9% disability. Mean MISS scores for death and disability were 35.1 and 29.6, respectively. Neurologic injuries were present in 274 patients (74%). 163 patients had severe head injury (coma greater than 6 h duration). 86% of all deaths were due to head injury and all but 2 deaths had some degree of head injury. The remaining 14% of deaths were due to chest and abdominal injuries. Patients with MISS grade 5 injury (critical, survival uncertain) had 74% mortality, while those with grades 4 and 3 injury had 8 and 1.5% mortality. In a comparison with pediatric patients with head injury only (coma greater than 6 h, no multiple trauma) there was found to be a 12% mortality in the head injury only group versus a 33% mortality in the multiple trauma plus head injury group. The MISS serves as an accurate predictor of morbidity and mortality in pediatric trauma. The best predictors of outcome were a MISS less than 25 and the degree of neurological injury.