Use of the Injury Severity Score in head injury.

As part of a study of the early management of severe head injury, the use of the Glasgow Coma Score (GCS), Injury Severity Score (ISS) and TRISS was investigated. These injury scores were compared in correlating with outcome at one year as assessed by the Glasgow Outcome Score (GOS) and mortality. One hundred and thirty-one patients had a severe head injury, as defined by an ISS of 16 or higher, in whom the Abbreviated Injury Score (AIS) for craniocerebral injury was 3 or higher. Seventy-eight of these also fulfilled the accepted GCS definition of severe head injury (GCS less than 8 with no eye-opening). Thirty-eight had evacuation of an acute intracranial haematoma; 26 of these patients would not have been classified as severe head injury by GCS. The overall mortality rate was 38 per cent, and 24 per cent for those transferred to the neurosurgical unit. TRISS was slightly better than GCS for predicting outcome based on both GOS and mortality, however this difference was not significant. TRISS identified patients who died that are not considered as severe head injury by GCS. Use of TRISS allows the effects of systemic factors and other injuries to be taken into account when assessing severity of head injury.