[Threshold levels of intracranial pressure as determinants of survival from diffuse brain injury. An observational...

Intracranial pressure (ICP) is frequently monitored in patients with severe head injuries. In this study of a series of diffuse brain injury patients, we investigated whether there are significant threshold levels that determine the outcome.

Data were obtained from 17 patients with severe head injuries (adults aged ≥ 15-years-old). The outcome was categorized using the Glasgow Outcome Scale and survival or death. Patients were also grouped according to the Traumatic Coma Data Bank (TCDB) CT classification for diffuse injury: type I (n=0); II (n=5); III (n=10); IV (n=2).

The mortality rate was 29% (5 of 17 patients). The average initial ICP within 24 hours (14.08 mmHg) and the peak ICP (26.75 mmHg) were lower in the survivors than that in the patients who died (57.60 mmHg and 91.00 mmHg, respectively; p=0.0006 and 0.0002, respectively). Patients with an initial ICP score>35 mmHg did not survive, and patients with a peak ICP<35 mmHg, except one who died of a traumatic brainstem hemorrhage, did survive. Using an X-bar chart, a threshold value for the initial ICP within 24 hours of 27 mmHg and for the peak ICP 46 mmHg appear to be the survival predictors in patients with diffuse brain injury.