RE-EXAMING THE CONCEPT OF SEVERITY IN TRAUMATIC BRAIN INJURY

This paper re-examines the theoretical concept of severe brain injury focusing on the duration of coma as a precise indicator of the clinica l profile. A retrospective hospital chart study of 361 traumatic brain -injured patients was undertaken to determine the homogeneity of the s ubsample of the severely brain-injured (defined as 2 or more days of c oma) with respect to the probability of four types of impairment: atax ia, contractures, paralysis and speech impairment. The current concept of severity assumes homogeneity among the 'severely brain-injured'. H owever, our results indicate significant differences in impairment wit hin this population. The authors feel strongly that future studies mus t describe coma duration in finer gradations, and test for homogeneity within samples before inferences are made. Improvements in life-susta ining technologies have resulted in longer coma durations. The need to use coma days as an indicator of impairment rather than a broad categ ory of severity is emphasized.