[Prognostic value of ICP, CPP and regional blood flow monitoring in diffuse and focal traumatic cerebral lesions].

ABSTRACT

Forty patients with severe traumatic brain injury (GCS score 8 and less) aged 16-54 years treated in our clinic were analyzed. Correlations between clinical symptoms, CT signs of diffuse and focal traumatic lesions, intracranial hemorrhage, indices of cerebral blood flow (CBF) according to perfusion CT study, intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were assessed. Main mechanism of injury in 27 of 40 (67.5%) patients was acceleration-deceleration due to traffic accidents which usually leads to diffuse axonal injury (DAI) of different severity. In the other 13 (32.5%) cases injury was associated with coup-countercoup mechanism which caused focal contusions mostly. Not only GCS score but CT-signs of DAI severity, intracranial hemorrhage and minimal levels of CPP had significant prognostic value. Results of perfusion CT studies demonstrated that in 37 of 40 (92.5%) patients cerebral blood flow decreased (below 28.6 ml/100 g/min) in one or more arterial blood distribution areas. Increase of CBF was registered in 9 cases (over 69 ml/100 g/min), in 6 of them elevation of CBF in one arterial distribution area was associated with reduction in the other. Generally, mean CBF values were higher in the middle cerebral artery circulation than in the other. The lowest CBF levels (16.3 +/- 6 ml/100 g/min) were observed in cortical and subcortical hemorrhagic foci while these values were significantly higher in the same contralateral intact zones (36.0 +/- 10.0 ml/100 g/min; p < 0.01). In 3 patients with DAI the CBF in the midbrain varied from 12.5 to 30.1 ml/100 g/min with the lowest levels in hemorrhagic focus in cerebral peduncle. It corresponded to cystic-atrophic alterations found on subsequent follow-up MRI. Thus, reduction of CBF and episodes of low CPP were the leading pathophysiological phenomena of diffuse and focal brain damages.