title: Can perinatal asphyxia cause cerebral edema and affect cerebral blood flow velocity?
abstract: Cerebral blood flow velocity (C.B.F.V.) was estimated in 49 newborn babies by calculating the pulsatility-index (P.I.) of the anterior cerebral arteries (A.C.A.) using Doppler ultrasound. We studied the changes in P.I. of the A.C.A. in relation to the clinical condition in three full-term babies with evidence of cerebral edema (in one patient proved by autopsy) due to perinatal asphyxia. There was a relation between the level of consciousness and the P.I.; a low P.I. (a sign of arterial vasodilatation) occurred with a low level of consciousness, while higher P.I. values (reduced vasodilatation) were detected when improvement of consciousness occurred. The following explanation is given: cerebral edema causes an increase of intracranial pressure and venous obstruction. The cerebral perfusion decreases and cerebral function changes; stupor and coma occur. By vasodilatation the resistance of the cerebral arteries is lowered; the C.B.F.V. increases in an attempt to restore cerebral perfusion. The vasodilation is reflected in the low P.I. values, as we found in our three patients.
mesh_terms: D000328:Adult; D001238:Asphyxia Neonatorum / Q000150:complications* / Q000503:physiopathology; D001783:Blood Flow Velocity; D001929:Brain Edema / Q000209:etiology*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000503:physiopathology; D007427:Intracranial Pressure; D008297:Male; D013997:Time Factors; D014655:Vascular Resistance