Traumatic brain contusions have been associated with regional ischemia. We aimed to measure the effect of induced supra-normal values of cerebral perfusion pressure (CPP) on regional cerebral blood flow (rCBF) in the intracontusional low density area surrounding the contusional hemorrhagic core. In 7 severely head injured patients (GCS < or = 8) harbouring a contusion larger than 2 cm, the rCBF levels were measured, by means of Xenon-enhanced CT, in: 1) the intracontusional low density area: 2) contralaterally, in a normal brain symmetric area. CBF studies were performed at a baseline CPP of 65.3 mmHg +/- 7 and after 20 minutes of norepinephrine-induced CPP supernormal values (88.3 mmHg +/- 10.5) (p = 0.0013). A "paradoxical" reduction of rCBF levels was observed in both the intracontusional low density area (p = 0.07) and the contralateral "normal" area (p = 0.08). In particular, this decrease of rCBF in the intracontusional low density area (-25.7 + 10 ml/100gr/min) (p = 0.0009) was present in only 4 cases, having a mean rCBF at baseline of 25 +/- 16 ml/100gr/min. In the remaining 3 cases in which rCBF at baseline was abnormally low (12 +/- 7 ml/ 100gr/min), rCBF values improved slightly (3.6 +/- 2 ml/100gr/min) (p = 0.61). An acute increase of CPP seems to marginally affect rCBF in the intracontusional low density area having critically reduced initial values, but may greatly reduce rCBF in subjects starting from non-critical baseline values.
|Titolo:||Induced acute arterial hypertension and regional cerebral flow in intracontusional low density area.|
|Data di pubblicazione:||2003|
|Appare nelle tipologie:||1.1 Articolo in rivista|