Adding insult to injury: the prognostic value of early secondaryinsults for survival after traumatic brain injury

摘要

OBJECTIVES—To assess the prognostic value of summary measures of secondary physiological insult in addition to baseline clinical variables for patients with traumatic brain injury.
METHODS—A series of 110 patients with traumatic brain injury had data on intracranial pressure (ICP), arterial blood pressure (ABP), cerebral perfusion pressure (CPP), arterial O2 saturation (SaO2), temperature in °C (Temp), and heart rate in beats/min (HRT) monitored and recorded every minute. Secondary insults were defined according to the Edinburgh University secondary insult grading system. The prognostic value of summary measures of these secondary insults was assessed by adding them to a prognostic model for survival at 1 year after controlling for baseline clinical variables using a previously validated model.
RESULTS—Of the eight secondary insults measured, only ICP added significantly to the prediction of survival in the first 72 hours after injury. The particular type of summary measure did not seem to influence the results. After the addition of ICP to the model, none of the other secondary insult measures could improve the predictive power of the model significantly.
CONCLUSIONS—Earlyintracranial hypertension is confirmed as a sign of poor prognosis inpatients with traumatic brain injury, even after controlling forbaseline clinical variables. The value or otherwise of treating suchsecondary insults, however, can only be definitively established in thecontext of prospective randomised controlled trials. The specificpathophysiological evolution of secondary insults is still the subjectof much research, and a clear understanding will be necessary beforethe development of specific treatments is feasible.