Церебральный кровоток при операциях с искусственным кровообращением

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Abstract

The aim of the present study was to study the perioperative changes of cerebral blood flow in on-pump operations. Sixty six patients were assessed using transcranial Doppler. During on-pump period mean velocity of blood flow in middle cerebral arteries (CBF) decreased in 60.5% of patients (t=3,5, p=0,001), and this finding is consistent with previous studies, which showed slowing of cerebral blood flow during hypothermia. After surgery systolic velocity of CBF increased in 74% patients (t=4,0, p<0,001), and diastolic CBF increased in 58% patients. In the majority of cases hemorheological status was characterized by signs of hemodilution. In contrast to previous studies, we did not find significant correlations between cerebral hemodinamics and hemoglobine/hematocrite level. Nevertheless, volume of blood loss, which was registered before on-pump period, correlated significantly with blood flow velocity during intraoperative and postoperative period. In addition, prothrombine time correlated significantly with cerebral hemodynamics. The present results evidence, that cerebral hemodynamics changes considerably during on-pump and after on-pump. Hemorheology is an important factor in hemodynamics changes.

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Chief Editor

Leo A. Bockeria, MD, PhD, DSc, Professor, Academician of Russian Academy of Sciences, President of Bakoulev National Medical Research Center for Cardiovascular Surgery